jEdit 5.3 User`s Guide

jEdit 5.3 User`s Guide
jEdit 5.3 User's Guide
The jEdit all-volunteer developer team
jEdit 5.3 User's Guide
The jEdit all-volunteer developer team
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each as defined in the license. A copy of the license can be found in the file COPYING.DOC.txt included with jEdit.
I. Using jEdit ............................................................................................................... 1
1. Conventions ..................................................................................................... 2
2. Starting jEdit .................................................................................................... 3
Command Line Usage ................................................................................... 3
Miscellaneous Options ........................................................................... 4
Configuration Options ............................................................................ 4
Edit Server Options ............................................................................... 4
Java Virtual Machine Options ........................................................................ 5
3. jEdit Basics ...................................................................................................... 7
Interface Overview ........................................................................................ 7
Multiple Views ............................................................................................. 7
Switching Buffers ......................................................................................... 8
Buffer Sets .................................................................................................. 9
Window Docking Layouts .............................................................................. 9
The Status Bar ............................................................................................ 10
The Action Bar ........................................................................................... 11
4. Working With Files ......................................................................................... 13
Creating New Files ...................................................................................... 13
Opening Files ............................................................................................. 13
Saving Files ............................................................................................... 13
Two-Stage Save .................................................................................. 14
Autosave and Crash Recovery ............................................................... 14
Backups ............................................................................................. 14
Line Separators ........................................................................................... 15
Character Encodings .................................................................................... 15
Commonly Used Encodings .................................................................. 16
The File System Browser (FSB) .................................................................... 16
Navigating the File System ................................................................... 17
The Tool Bar ...................................................................................... 17
The Commands Menu .......................................................................... 17
The Plugins Menu ............................................................................... 18
The Favorites Menu ............................................................................. 18
Keyboard Shortcuts ............................................................................. 18
Reloading From Disk ................................................................................... 18
Task Monitor, and background I/O tasks ......................................................... 19
Printing ..................................................................................................... 19
Closing Files and Exiting jEdit ...................................................................... 19
5. Editing Text ................................................................................................... 20
Moving The Caret ....................................................................................... 20
Selecting Text ............................................................................................. 21
Range Selection .................................................................................. 21
Rectangular Selection ........................................................................... 21
Multiple Selection ............................................................................... 21
Keyboard Focus ......................................................................................... 22
Inserting and Deleting Text ........................................................................... 23
Undo and Redo ........................................................................................... 23
Working With Words ................................................................................... 23
What's a Word? .................................................................................. 24
Working With Lines .................................................................................... 24
Working With Paragraphs ............................................................................. 24
Wrapping Long Lines .................................................................................. 25
Soft Wrap .......................................................................................... 25
Hard Wrap ......................................................................................... 25
Scrolling .................................................................................................... 26
Transferring Text ........................................................................................ 26
The Clipboard ..................................................................................... 26
Quick Copy ........................................................................................ 27
General Register Commands ................................................................. 27
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jEdit 5.3 User's Guide
6.
7.
8.
9.
Markers .....................................................................................................
Search and Replace .....................................................................................
Searching For Text ..............................................................................
Replacing Text ...................................................................................
HyperSearch .......................................................................................
Multiple File Search ............................................................................
The Search Bar ...................................................................................
Editing Source Code ........................................................................................
Edit Modes ................................................................................................
Mode Selection ...................................................................................
Syntax Highlighting .............................................................................
Tabbing and Indentation ...............................................................................
Soft Tabs ...........................................................................................
Elastic Tabstops ..................................................................................
Automatic Indent .................................................................................
Commenting Out Code .................................................................................
Bracket Matching ........................................................................................
Abbreviations .............................................................................................
Positional Parameters ...........................................................................
Folding ......................................................................................................
Collapsing and Expanding Folds ............................................................
Navigating Around With Folds ..............................................................
Miscellaneous Folding Commands ..........................................................
Narrowing ..........................................................................................
Customizing jEdit ............................................................................................
The Buffer Options Dialog Box .....................................................................
Buffer-Local Properties ................................................................................
The Global Options Dialog Box .....................................................................
The General Pane ................................................................................
The Abbreviations Pane ........................................................................
The Appearance Pane ..........................................................................
The Context Menu Pane .......................................................................
The Docking Pane ...............................................................................
The Editing Pane ................................................................................
The Encodings Pane ............................................................................
The Gutter Pane ..................................................................................
The Mouse Pane .................................................................................
The Plugin Manager Pane .....................................................................
The Printing Pane ................................................................................
The Proxy Servers Pane .......................................................................
The Saving and Backup Pane ................................................................
The Shortcuts Pane ..............................................................................
The Status Bar Pane ............................................................................
The Syntax Highlighting Pane ...............................................................
The Text Area Pane .............................................................................
The Tool Bar Pane ..............................................................................
The View Pane ...................................................................................
The File System Browser Panes .............................................................
The jEdit Settings Directory ..........................................................................
The jEdit properties file ........................................................................
Site Properties ....................................................................................
Using Macros .................................................................................................
Recording Macros .......................................................................................
Running Macros ..........................................................................................
How jEdit Organizes Macros .........................................................................
Installing and Using Plugins ..............................................................................
The Plugin Manager ....................................................................................
Installing and Updating Plugins .....................................................................
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jEdit 5.3 User's Guide
Plugin Sets ................................................................................................. 53
A. Keyboard Shortcuts ......................................................................................... 54
B. The Activity Log ............................................................................................ 59
C. History Text Fields .......................................................................................... 60
D. Glob Patterns ................................................................................................. 61
E. Regular Expressions ........................................................................................ 62
F. Macros Included With jEdit .............................................................................. 64
C/C++ macros ............................................................................................ 64
Clipboard Macros ........................................................................................ 64
Editing Macros ........................................................................................... 65
File Management Macros .............................................................................. 66
User Interface Macros .................................................................................. 67
Java Code Macros ....................................................................................... 68
Miscellaneous Macros .................................................................................. 69
Property Macros .......................................................................................... 70
Text Macros ............................................................................................... 70
II. Writing Edit Modes ................................................................................................. 72
10. Mode Definition Syntax .................................................................................. 73
An XML Primer ......................................................................................... 73
The Preamble and MODE tag ........................................................................ 74
The PROPS Tag ......................................................................................... 74
The RULES Tag ......................................................................................... 76
Highlighting Numbers .......................................................................... 77
Rule Ordering Requirements ................................................................. 77
Per-Ruleset Properties .......................................................................... 78
The TERMINATE Tag ................................................................................ 78
The SPAN Tag ........................................................................................... 78
The SPAN_REGEXP Tag ............................................................................. 79
The EOL_SPAN Tag ................................................................................... 80
The EOL_SPAN_REGEXP Tag ..................................................................... 80
The MARK_PREVIOUS Tag ........................................................................ 81
The MARK_FOLLOWING Tag .................................................................... 81
The SEQ Tag ............................................................................................. 82
The SEQ_REGEXP Tag ............................................................................... 82
The IMPORT Tag ....................................................................................... 83
The KEYWORDS Tag ................................................................................. 83
Token Types .............................................................................................. 84
The MATCH_TYPE Attribute ....................................................................... 85
11. Installing Edit Modes ...................................................................................... 87
12. Updating Edit Modes ...................................................................................... 89
From jEdit 4.2 to 4.4 ................................................................................... 89
III. Writing Macros ..................................................................................................... 90
13. Macro Basics ................................................................................................ 91
Introducing BeanShell .................................................................................. 91
Single Execution Macros .............................................................................. 91
The Mandatory First Example ....................................................................... 92
Predefined Variables in BeanShell .................................................................. 94
Helpful Methods in the Macros Class ............................................................. 94
BeanShell Dynamic Typing ........................................................................... 96
Now For Something Useful ........................................................................... 96
14. A Dialog-Based Macro ................................................................................... 98
Use of the Macro ........................................................................................ 98
Listing of the Macro .................................................................................... 98
Analysis of the Macro ................................................................................ 100
Import Statements .............................................................................. 100
Create the Dialog .............................................................................. 100
Create the Text Fields ........................................................................ 101
Create the Buttons ............................................................................. 102
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jEdit 5.3 User's Guide
Register the Action Listeners ............................................................... 102
Make the Dialog Visible ..................................................................... 103
The Action Listener ........................................................................... 103
Get the User's Input ........................................................................... 103
Call jEdit Methods to Manipulate Text .................................................. 104
The Main Routine .............................................................................. 105
15. Macro Tips and Techniques ........................................................................... 106
Getting Input for a Macro ........................................................................... 106
Getting a Single Line of Text .............................................................. 106
Getting Multiple Data Items ................................................................ 106
Selecting Input From a List ................................................................. 108
Using a Single Keypress as Input ......................................................... 109
Startup Scripts ........................................................................................... 110
Running Scripts from the Command Line ...................................................... 111
Advanced BeanShell Techniques .................................................................. 112
BeanShell's Convenience Syntax .......................................................... 112
Special BeanShell Keywords ............................................................... 112
Implementing Classes and Interfaces ..................................................... 113
Debugging Macros ..................................................................................... 114
Identifying Exceptions ........................................................................ 114
Using the Activity Log as a Tracing Tool ............................................... 114
16. BeanShell Commands ................................................................................... 116
Output Commands ..................................................................................... 116
File Management Commands ....................................................................... 116
Component Commands ............................................................................... 117
Resource Management Commands ................................................................ 117
Script Execution Commands ........................................................................ 117
BeanShell Object Management Commands ..................................................... 118
Other Commands ....................................................................................... 119
IV. Writing Plugins .................................................................................................... 120
17. Introducing the Plugin API ............................................................................ 121
18. Implementing a Simple Plugin ........................................................................ 123
How Plugins are Loaded ............................................................................ 123
The QuickNotepadPlugin Class .................................................................... 124
The Property Files ..................................................................................... 126
Localization Files ............................................................................. 128
The EditBus ............................................................................................. 128
The Actions.xml Catalog ............................................................................. 129
The dockables.xml Window Catalog ............................................................. 130
The services.xml file .................................................................................. 131
The QuickNotepad Class ............................................................................. 131
The QuickNotepadToolBar Class .................................................................. 134
The QuickNotepadOptionPane Class ............................................................. 135
Plugin Documentation ................................................................................ 136
The build.xml Ant build file ........................................................................ 137
Reloading the Plugin .................................................................................. 138
Tips for debugging plugins ......................................................................... 138
19. Plugin Tips and Techniques ........................................................................... 139
Utility Classes .......................................................................................... 139
Bundling Additional Class Libraries .............................................................. 139
Bundling Additional Non-Java Libraries ........................................................ 139
Storing plugin data .................................................................................... 139
Plugin colors ............................................................................................. 139
vi
Part I. Using jEdit
This part of the user's guide covers jEdit's text editing commands, along with basic usage of macros and plugins.
This part of the user's guide was originally written by Slava Pestov and is maintained by the jEdit core
development team.
Chapter 1. Conventions
Several conventions are used throughout jEdit's user interface and this manual. They will be
described here. Macintosh users should note how their modifier keys map to the terms used in the
manual.
View>Scrolling>Scroll to Current Line
The Scroll to Current Line command contained
in the Scrolling submenu of the View menu.
Edit>Go to Line...
Menu items that end with ellipsis (...) display
dialog boxes.
C
The primary modifier key in jEdit. On
MacOS X, this is actually the key known as
“Command”. On most other keyboards, this key
is labelled “Control”.
A
The secondary modifier key in jEdit. On MacOS
X, this is actually the key labelled “Control”. On
most other keyboards, this key is labelled “Alt”.
S
The standard “Shift” key.
C+o
Refers to pressing and holding the Control
key, pressing and releasing O, and finally
releasing the Control key.
C+e C+j
Refers to holding down Control, pressing E,
pressing J, and releasing Control.
Default buttons
In many dialog boxes, the default button
(it has a heavy outline, or a special border,
depending on the current Swing look and feel)
can be activated by pressing Enter. Similarly,
pressing Escape will usually close a dialog
box.
Alt-key mnemonics
Some user interface elements (menus, menu
items, buttons) have a certain letter in their label
underlined. Pressing this letter in combination
with the Alt key activates the associated user
interface widget. The "F10" key can also be
pressed to put focus on the menu bar, it has the
same functionality as the Alt key in Windows.
Note that this functionality is not available on
MacOS X with the “MacOS Adaptive” look and
feel. See the section called “The Appearance
Pane” for information on changing the look and
feel.
Right mouse button
Used in jEdit to show context-sensitive menus.
If you have a one button Macintosh mouse, a
Control-click has the same effect.
Middle mouse button
Used by the quick copy feature (see the section
called “Quick Copy”). True 3-button mice are
rare these days. If you have a wheel mouse,
press down on the wheel without rolling it. On a
Macintosh with a one-button mouse, Optionclick. On other platforms without a three-button
mouse, Alt-click.
2
Chapter 2. Starting jEdit
Exactly how jEdit is started depends on the operating system. For example, on Unix you can run
“jedit” at the command line, or select jEdit from a menu; on Windows, you can double-click on the
jEdit icon or select it from the Start menu.
If jEdit is started while another copy is already running, control is transferred to the running copy,
and a second instance is not loaded. This saves time and memory if jEdit is started multiple times.
Communication between instances of jEdit is implemented using TCP/IP sockets; the initial
instance is known as the server, and subsequent invocations are clients.
If you find yourself launching and exiting jEdit a lot, the startup time can get a bit bothersome. If the
-background command line switch is specified, jEdit will continue running and waiting for client
requests even after all editor windows are closed. When run in background mode, you can open and
close jEdit any number of times, only having to wait for it to start the first time. The downside of
this is increased memory usage.
When running on MacOS X, the -background command-line switch is active by default, so that
jEdit conforms to the platform convention that programs should stay open until the Quit command
is explicitly invoked by the user, even if all windows are closed. To disable background mode on
MacOS X, use the -nobackground switch.
For more information about command line switches that control the server feature, see the section
called “Command Line Usage”.
jEdit remembers open buffers, views and split window configurations between editing sessions,
so you can get back to work immediately after starting jEdit. This feature can be disabled in the
General pane of the Utilities>Options dialog box see the section called “The General Pane”.
The edit server and security
Since Java does not provide any interprocess communication facility other than TCP/IP, jEdit
takes extra precautions to prevent remote attacks.
Not only does the edit server pick a random TCP port number on startup, it also requires
that clients provide an authorization key; a randomly-generated number only accessible to
processes running on the local machine. So not only will “bad guys” have to guess a 64bit integer, they will need to get it right on the first try; the edit server shuts itself off upon
receiving an invalid packet.
In environments that demand absolute security, the edit server can be disabled by specifying
the -noserver command line switch.
Command Line Usage
On operating systems that support a command line, jEdit can be passed various arguments to control
its behavior.
When opening files from the command line, a line number or marker to position the caret on can be
specified like so:
$ jedit MyApplet.java +line:10
$ jedit thesis.tex +marker:c
Command-line switches begin with a "-". Some take a parameter. A file whose name begins with "-"
can be opened like so:
3
Starting jEdit
$ jedit -- -myfile
Miscellaneous Options
Option
Effect
-log=level
Set the minimum log level to an integer between 1 and 9. Default is 7.
Has no effect when connecting to another instance via the edit server.
-usage
Show a brief command line usage message without starting jEdit. This
message is also shown if an invalid switch was specified.
-version
Show the version number without starting jEdit.
-nosplash
Don't show the splash screen on startup.
--
Specifies the end of command-line processing. Further parameters are
treated as file names, even if they begin with a dash.
Configuration Options
Option
Effect
-plugins
Enable loading of plugins. Has no effect when connecting to another
instance via the edit server. See Chapter 9, Installing and Using Plugins.
-noplugins
Disable loading of plugins. Has no effect when connecting to another
instance via the edit server.
-restore
Restore previously open files on startup. This is the default. This feature
can also be set permanently in the General pane of the Utilities> Options
dialog box; see the section called “The General Pane”.
-norestore
Do not restore previously open files on startup.
-run=script
Run the specified BeanShell script. There can only be one of these
parameters on the command line. See the section called “Running Scripts
from the Command Line”.
-settings=dir
Store user-specific settings in the directory named dir, instead of
the default user.home/.jedit. The directory will be created
automatically if it does not exist. Has no effect when connecting to
another instance via the edit server. See the section called “The jEdit
Settings Directory”.
-nosettings
Start jEdit without loading user-specific settings.
-startupscripts
Run startup scripts. This is the default. Has no effect when connecting
to another instance via the edit server. See the section called “Startup
Scripts”.
Disable startup scripts. Has no effect when connecting to another instance
nostartupscripts via the edit server.
Edit Server Options
See Chapter 2, Starting jEdit for a brief description of the edit server.
Option
Effect
-background
Run jEdit in background mode. In background mode, the edit server will
continue listening for client connections even after all views are closed.
Has no effect when connecting to another instance via the edit server.
-nobackground
Disable background mode. This is the default. Has no effect when
connecting to another instance via the edit server.
4
Starting jEdit
Option
Effect
-gui
Open an initial view. This is the default. Has no effect when connecting to
another instance via the edit server.
-nogui
Do not open an initial view, and instead only open one when the
first client connects. Can only be used in combination with the background switch. You can use this switch to “pre-load” jEdit when
you log in to your computer, for example. Has no effect when connecting
to another instance via the edit server.
-newplainview
Opens the specified files in a new plain view. For more information about
views, see the section called “Multiple Views”.
-newview
Opens the specified files in a new view.
-reuseview
Opens the specified files in an existing view.
-quit
Exits the currently running editor instance.
-server
Store the server port info in the file named server inside the settings
directory.
-server=name
Store the server port info in the file named name. File names for this
parameter are relative to the settings directory.
-noserver
Do not attempt to connect to a running edit server, and do not start one
either.
-wait
Keeps the client open until the user closes the specified buffer in the
server instance. Does nothing if passed to the initial jEdit instance. Use
this switch if jEdit is being invoked by another program as an external
editor; otherwise the client will exit immediately and the invoking
program will assume you have finished editing the given file.
Java Virtual Machine Options
To enable AntiAliasing in the TextArea, see the section called “The Text Area Pane”.
It is possible to pass command line options to the Java Virtual Machine (JVM). These options can
change certain things about how Java runs, such as the maximum heap size, or whether antialiasing
is used in certain places.
For operating systems such as Linux where jEdit is started via a shell script, you can easily edit the
jedit script and place JVM arguments in the correct place. If you are using the -jar command
line option with the java command to run jEdit (which is how the default shell scripts do it),
remember that the -jar parameter must be the last java option, followed immediately by the path
to jedit.jar and then any jEdit command line options.
On a Windows install that uses jEdit.exe, the JVM options are located in a separate file, called
jEdit.l4j.ini. Create or edit this file in the same directory as jEdit.exe and place one
JVM option per line.
On Mac OS X, the jEdit.app bundle gets JVM options from a file called Contents/
Info.plist, which can be edited with a text editor.
There is no complete list of options to java, since it can vary from one platform to another. Some
of can be found by typing the commands java -? or man java. Common JVM options that are
used with jEdit and work on all platforms are:
Option
Effect
Antialias the text in AWT components.
Dawt.useSystemAAFontSettings=on
5
Starting jEdit
Option
Effect
Antialias the text in Swing components.
Dswing.aatext=true
-Djedit.home=/
path/to/jedit
Sets/overrides the java System property jedit.home to be the path to
the jEdit install. This tells jEdit where to find its site properties, default
keymaps, macros, edit modes, and documentation. You can override this
setting to create a custom install that is shared by multiple users. See the
section called “Site Properties” for more information.
-mx768m
Sets maximum heap size to 768 megabytes. Adjust this value depending
on your own personal needs / plugins. On at least one platform, Xmx768m works when -mx768m does not (or vice-versa).
6
Chapter 3. jEdit Basics
Interface Overview
A View is the jEdit term for an editor main window. It is possible to have multiple views open
at once, and each View can be split into multiple panes. jEdit remembers the state of open views
between editing sessions.
An open file is referred to as a Buffer. Unlike some editors where each buffer gets its own View,
jEdit completely separates the two concepts. A buffer might be visible in several views, or none at
all.
A TextArea is an editor for a buffer. An EditPane contains a TextArea plus optional buffer switcher.
A View contains one EditPane by default, and additional panes are created whenever the View is
split.
The drop-down buffer switcher list at the top of each EditPane shows a BufferSet, or a set of open
buffers (see the section called “Buffer Sets”). Selecting a buffer on this list will make it visible
in the TextArea. Different emblems are displayed next to buffer names in the list, depending the
buffer's state; a red disk is shown for buffers with unsaved changes, a lock is shown for read-only
buffers, and a spark is shown for new buffers which don't yet exist on disk.
With the new Tango icon theme, these symbols are slightly different, a red square is shown for
buffers with unsaved changes, a lock is shown for read-only buffers, and a yellow square is shown
for new buffers which don't yet exist on disk.
As with most other graphical applications, there is a tool bar at the top of the View which provides
quick access to frequently-used commands. Also, clicking the TextArea with the right mouse button
displays a popup menu which also facilitates quick access to various commands. Both the tool bar
and the right-click menu can be completely customized to suit your tastes in the Utilities>Options
dialog box; see the section called “The Context Menu Pane” and the section called “The Tool Bar
Pane”.
Most of the View is taken up by the TextArea. If you've ever used a graphical user interface before,
the TextArea will be instantly familiar. Text can be inserted simply by typing. More details on text
insertion and deletion can be found in the section called “Inserting and Deleting Text”.
The strip on the left of the TextArea is called a gutter. The gutter displays marker and register
locations, as well as folding arrows; it will also display line numbers if the View>Line Numbers
(shortcut: C+e C+t) command is invoked. Note this menu toggle action has the side-effect of
changing the persistent jEdit properties for the Gutter, which can also be set from the Gutter pane
of the Utilities>Options dialog box.
The gutter is divided into two sections. Right-clicking on the left side gives you a context menu,
while right-clicking on the right side (where line numbers might be) toggles a marker at that
position. Text can be selected by left-clicking and dragging on right side of the gutter, over the
range of lines you wish to select.
Multiple Views
As documented at the beginning of this chapter, multiple Views (main windows) can be open at
once.
View>New View creates a new View, or main window.
View>New Plain View creates a new View but without any tool bars or dockable windows. This
can be used to open a small window for taking notes and so on.
7
jEdit Basics
View>Close View closes the current View. If only one View is open, closing it will exit jEdit,
unless background mode is on; see Chapter 2, Starting jEdit for information about starting jEdit in
background mode.
View>Split Horizontally (shortcut: C+2) splits the View into two TextAreas, placed above each
other.
View>Split Vertically (shortcut: C+3) splits the View into two TextAreas, placed next to each
other.
Macros>Interface> Splitpane Grow grows the size of the currently focused TextArea.
View>Unsplit Current (shortcut: C+0) removes the split containing the current TextArea only.
View>Unsplit All (shortcut: C+1) removes all splits from the View.
When a View is split, editing commands operate on the TextArea that has keyboard focus. To give a
TextArea keyboard focus, click in it with the mouse, or use the following commands.
View>Go to Previous Text Area (shortcut: A+PAGE_UP) shifts keyboard focus to the previous
TextArea.
View>Go to Next Text Area (shortcut: A+PAGE_DOWN) shifts keyboard focus to the next
TextArea.
Switching Buffers
Each EditPane has an optional drop-down BufferSwitcher at the top. The BufferSwitcher shows the
current buffer and can also be used to switch the current buffer, using menu item commands and
their keyboard shortcuts.
View>Go to Previous Buffer (keyboard shortcut: C+PAGE_UP) switches to the previous buffer in
the list.
View>Go to Next Buffer (keyboard shortcut: C+PAGE_DOWN) switches to the next buffer in the
list.
View>Go to Recent Buffer (keyboard shortcut: C+BACK_QUOTE) flips between the two most
recently edited buffers.
View>Show Buffer Switcher (keyboard shortcut: A+BACK_QUOTE) has the same effect as
clicking on the buffer switcher combo box.
If you prefer an alternative graphical paradigm for switching buffers, take a look at one of these
plugins:
• BufferList
• BufferSelector
• BufferTabs
If you decide to use one of these plugins, you can hide the popup menu buffer switcher in the View
pane of the Utilities>Options dialog box.
A number of plugins that implement fast keyboard-based buffer switching are available as well:
• FastOpen
• OpenIt
• SwitchBuffer
8
jEdit Basics
Buffer Sets
The buffer sets feature helps keep the buffer lists local and manageable when using jEdit in a
multiple-View and multiple-EditPane environment.
As mentioned in the previous section, each EditPane can show a Buffer Switcher, which displays
the contents of a BufferSet. In jEdit 4.2, all EditPane buffer switchers showed the same BufferSet: a
global list of all buffers that were opened from any EditPane in any View. When using many Views
and EditPanes, this resulted in large lists of buffers, and made the next/previous buffer actions
useless with many Views, EditPanes and Buffers.
Since jEdit 4.3, it is possible to have more narrow scopes for the BufferSets of an EditPane. This
makes the 'next-buffer' and 'previous-buffer' actions switch between buffers that are local to the
view or pane.
The three BufferSet scopes are:
1. Global: Includes all buffers open from any EditPane.
2. View: EditPanes in the same View share the same BufferSet. Opening a buffer in one View will
not affect the other views.
3. EditPane: Each EditPane can have its own independent BufferSet.
Bufferset scope can be set from Utilities >Options > View > BufferSet scope:.
File > Close removes the current buffer from the EditPane's BufferSet only. If it was the last
BufferSet to contain that buffer, the buffer is also closed.
The File > Close (global) action closes the buffer in all EditPanes, as the jEdit 4.2 File > Close
action did before.
When Exclusive Buffersets are enabled, any time a buffer is visited in one EditPane, it should be
automatically closed in other EditPanes which use a disjoint (non-intersecting) BufferSet.
Close Others will clear the BufferSet of the current EditPane by performing a Close on all items
except those buffers which are displayed in another active EditPane.
Switching Bufferset Scopes
The statusbar shows you which BufferSet scope is active (look for the letter "G", "E" or "V").
Double-clicking on that will allow you to change the scope without going into global options. The
BufferSet Scope can also be changed from View>Buffer Sets > (Global|View|EditPane) Buffer
Set. A change to the bufferset scope affects all editpanes immediately.
Sorting of Buffer Sets and Buffer Switchers
Buffer Switchers and Buffer Sets can be sorted independently. Both can be sorted by name or
by path. Both can be left unsorted. Possibly the most useful combination is to sort the Buffer
Switchers and leave the Buffer Sets unsorted. In this case, it is easy to find the buffer to work with
in the Buffer Switcher since the buffer names are sorted alphabetically, and leaving the Buffer Set
unsorted means the "go to previous" and "go to next" actions follow the order in which the buffers
were last used rather than by name. However, some users prefer Buffer Sets to also be sorted by
name or path, so jEdit supports multiple sorting methods.
Window Docking Layouts
A docking layout is similar to an Eclipse "Perspective" in that it describes a set of dockable
windows that are visible to the user at any given time, hiding the rest.
9
jEdit Basics
Various jEdit and plugin windows can be docked into the View for convenience. Dockable windows
have a popup button in their top-left corner. Clicking this button displays a menu with commands
for docking the window in one of four sides of the View.
On each side of the TextArea where there are docked windows, a strip of buttons is shown. There is
a button for activating each docked window, as well as a close box and a popup menu button, which
when clicked shows a menu for moving or undocking the currently selected window. The popup
menu also contains a command for opening a new floating instance of the current window.
The commands in the View>Docking menu move keyboard focus between docking areas.
After you have customized the layout of your dockables and wish to save it for export/import, use
the actions View - Docking - Save/Load Docking Layout.
It is possible to configure a Dockable layout for just one or a handful of edit modes. This makes it
possible to save or load your dockable layout with the same keyboard shortcut (or automatically)
based on the edit mode of your current buffer.
It is also possible to save/load a layout for a particular edit mode. The loading and saving can be
done automatically, as configured in the global options docking pane when the mode of the buffer
changes, or manually in response to invoking View - Docking - Save/Load Docking Layout for
current mode.
Dockable windows can be further configured in the Docking pane of the Utilities>Global Options
dialog box. See the section called “The Docking Pane” for details.
For keyboard/power users
Each dockable has three commands associated with it; one is part of the menu bar and opens
the dockable. The other two commands are:
• Window Name (Toggle) - opens the dockable window if it is hidden, and hide it if its
already open.
• Window Name (New Floating Instance) - opens a new instance of the dockable in a
floating window, regardless of the docking configuration. For example, this can be used to
view two different directories side-by-side in two file system browser windows.
A new floating instance can also be opened from the dockable window's popup menu.
These commands cannot be invoked from the menu bar. However, they can be added to the
tool bar or context menu, and given keyboard shortcuts; see the section called “The Global
Options Dialog Box”.
The Status Bar
The status bar at the bottom of the View consists of the following components, from left to right:
• Caret position information:
• The offset of the caret from the beginning of the file
• The line number containing the caret
• The column position of the caret, with the leftmost column being 1.
If the line contains tabs, the file position (where a hard tab is counted as one column) is shown
first, followed by the screen position (where each tab counts for the number of columns until
the next tab stop).
10
jEdit Basics
• The percent offset of the caret from the start of the file. This is based on the line number of the
caret and the total number of lines in the file, so this is the same as the relative position of the
right scroll bar in the main text area.
Double-clicking on the caret location indicator displays the Edit>Go to Line dialog box; see the
section called “Working With Lines”.
• A message area where various prompts and status messages are shown.
• The current buffer's edit mode, fold mode, and character encoding. Double-clicking one of these
displays the Utilities>Buffer Options dialog box. For more information about these settings, see:
• the section called “The Buffer Options Dialog Box”
• the section called “Edit Modes”
• the section called “Folding”
• the section called “Character Encodings”
• A set of flags which indicate various editor features and settings. Clicking each flag will toggle
the feature in question; hovering the mouse over a flag will show a tool tip with an explanation:
• Word wrap - see the section called “Wrapping Long Lines”.
• Multiple selection - see the section called “Multiple Selection”.
• Rectangular selection - see the section called “Rectangular Selection”.
• Overwrite mode - see the section called “Inserting and Deleting Text”.
• Line separator - see the section called “Line Separators”.
• Buffer Set Scope - see the section called “Buffer Sets”.
• A Task Monitor widget, which spins with activity when a background task is running, and also
lists how many tasks are running. Clicking on this will open the Task Monitor dockable (the
section called “Task Monitor, and background I/O tasks”).
• A Java heap memory usage indicator, that shows used and total heap memory, in megabytes.
Double-clicking this indicator opens the Utilities>Troubleshooting>Memory Status dialog box.
The order and visibility of each of the above items can be controlled in the Status Bar pane of the
Utilities>Options dialog box; see the section called “The Status Bar Pane”.
The Action Bar
The action bar allows almost any editor feature to be accessed from the keyboard.
Utilities>Action Bar (shortcut: C+ENTER) displays the action bar at the bottom of the View and
gives it keyboard focus. The action bar remembers previously entered strings; see Appendix C,
History Text Fields for details.
To use the action bar, input a command and press Enter. The following commands are supported:
Action invocations
Each menu item and tool bar button is bound to an action. To find out the name of an action, invoke
the menu item or click the tool bar button, and look in the action bar's history.
11
jEdit Basics
If a substring or an action name is entered, pressing Tab shows a popup listing matching actions.
An action can be selected using the Up and Down arrow keys, or by entering more characters of its
name.
Pressing Enter with an incomplete substring invokes the action that would be first in the
completion popup's list.
For example, entering d-o will invoke combined-options, which has the same effect as
invoking Utilities> Options.
Buffer-local properties
Entering buffer.property=value sets the value of the buffer-local property named
property to value. Buffer-local properties are documented in the section called “Buffer-Local
Properties”.
For example, entering buffer.tabSize=4 changes the current buffer's tab size to 4.
See the section called “Buffer-Local Properties” for information about buffer-local properties.
Global properties
Entering property=value sets the value of the global property named property to value.
This feature is primarily intended to help plugin developers, since the properties jEdit uses to store
its settings are not currently documented.
Command repetition
To repeat a command multiple times, enter a number in the action bar, then press the keycombination that invokes the command. For example, “C+ENTER 1 4 C+d” will delete 14 lines; “C
+ENTER 9 #” will insert “#########” in the buffer. Note: The space characters in these examples
should not be typed; they are only here to visually separate the keys to be typed.
If you specify a repeat count greater than 20, a confirmation dialog box will be displayed, asking
if you really want to perform the action. This prevents you from hanging jEdit by executing a
command too many times.
12
Chapter 4. Working With Files
Creating New Files
File>New (shortcut: C+n) opens a new, empty, buffer. Another way to create a new file is to specify
a non-existent file name when starting jEdit on the command line. A new file will be created on disk
when the buffer is saved for the first time.
Opening Files
File>Open (shortcut: C+o) displays a file system browser dialog box and loads the specified file
into a new buffer.
Multiple files can be opened at once by holding down Control while clicking on them in the file
system browser. The file system browser supports auto-completion; typing the first few characters
of a listed file name will select the file.
More advanced features of the file system browser are described in the section called “The File
System Browser (FSB)”.
The File>Recent Files menu lists recently viewed files. When a recent file is opened, the caret is
automatically moved to its previous location in that file. The number of recent files to remember can
be changed and caret position saving can be disabled in the General pane of the Utilities>Options
dialog box; see the section called “The General Pane”.
The Utilities>Current Directory menu lists all files and directories in the current buffer's directory.
Selecting a file opens it in a buffer for editing; selecting a directory opens it in the file system
browser (see the section called “The File System Browser (FSB)”).
Note
Files that you do not have write access to are opened in read-only mode, where editing is
not permitted.
Tip
jEdit supports transparent editing of GZipped files; if a file begins with the GZip “magic
number”, it is automatically decompressed before loading and compressed when saving.
To compress an existing file, you need to change a setting in the Utilities>Buffer Options
dialog box; see the section called “The Buffer Options Dialog Box” for details.
Saving Files
Changed made in a buffer do not affect the file on disk until the buffer is saved.
File>Save (shortcut: C+s) saves the current buffer to disk.
File>Save As renames the buffer and saves it in a new location. Note that using this command to
save over another open buffer will close the other buffer, to stop two buffers from being able to
share the same path name.
File>Save a Copy As saves the buffer to a different location but does not rename the buffer, and
does not clear the “modified” flag. Note that using this command to save over another open buffer
will automatically reload the other buffer.
File>Save All (shortcut: C+e C+s) saves all open buffers to disk, asking for confirmation first. The
confirmation dialog can be disabled in the General pane of the Utilities>Options dialog box.
13
Working With Files
Two-Stage Save
To prevent data loss in the unlikely case that jEdit should crash in the middle of saving a file, files
are first saved to a temporary file named #filename#save#. If this operation is successful, the
original file is replaced with the temporary file.
However, in some situations, this behavior is undesirable. For example, on Unix this creates a new
i-node so while jEdit retains file permissions, the owner and group of the file are reset, and if it is a
hard link the link is broken. The “two-stage save” feature can be disabled in the General pane of the
Utilities>Options dialog box; see the section called “The General Pane”.
Autosave and Crash Recovery
The autosave feature protects your work from computer crashes and such. Every 30 seconds, all
buffers with unsaved changes are written out to their respective file names, enclosed in hash (“#”)
characters. For example, program.c will be autosaved to #program.c#.
Saving a buffer using one of the commands in the previous section automatically deletes the
autosave file, so they will only ever be visible in the unlikely event of a jEdit (or operating system)
crash.
If an autosave file is found while a buffer is being loaded, jEdit will offer to recover the autosaved
data.
The autosave interval can be changed in the Autosave and Backup pane of the Utilities>Options
dialog box; see the section called “The Saving and Backup Pane”.
Backups
The backup feature can be used to roll back to the previous version of a file after changes were
made. When a buffer is saved for the first time after being opened, its original contents are “backed
up” under a different file name.
The behavior of the backup feature is specified in the Autosave and Backup pane of the
Utilities>Options dialog box; see the section called “The Saving and Backup Pane”.
The default behavior is to back up the original contents to the buffer's file name suffixed with a tilde
(“~”). For example, a file named paper.tex is backed up to paper.tex~.
• The Max number of backups setting determines the number of backups to save. Setting this to
zero disables the backup feature. Settings this to more than one adds numbered suffixes to file
names. By default only one backup is saved.
• If the Backup directory setting is non-empty, backups are saved in that location (with the full
path to the original file under it). Otherwise, they are saved in the same directory as the original
file. The latter is the default behavior.
• The Backup filename prefix setting is the prefix that is added to the backed-up file name. This is
empty by default.
• The Backup filename suffix setting is the suffix that is added to the backed-up file name. This is
“~” by default.
• Backups can optionally be saved in a specified backup directory, instead of the directory of the
original file. This can reduce clutter.
• The Backup on every save option is off by default, which results in a backup only being created
the first time a buffer is saved in an editing session. If switched on, backups are created every
time a buffer is saved.
14
Working With Files
Line Separators
Unix systems use newlines (\n) to mark line endings in text files. The MacOS uses carriage-returns
(\r). Windows uses a carriage-return followed by a newline (\r\n). jEdit can read and write files
in all three formats.
The line separator used by the in-memory representation of file contents is always the newline
character. When a file is being loaded, the line separator used in the file on disk is stored in a
per-buffer property, and all line-endings are converted to newline characters for the in-memory
representation. When the buffer is consequently saved, the value of the property replaces newline
characters when the buffer is saved to disk.
There are several ways to change a buffer's line separator:
• In the Utilities>Buffer Options dialog box. See the section called “The Buffer Options Dialog
Box”.
• By clicking the line separator indicator in the status bar. See the section called “The Status Bar”.
• From the keyboard, if a keyboard shortcut has been assigned to the Toggle Line Separator
command in the Shortcuts pane of the Utilities> Options dialog box. By default, this command
does not have a keyboard shortcut.
By default, new files are saved with your operating system's native line separator. This can be
changed in the Encodings pane of the Utilities>Options dialog box; see the section called “The
Encodings Pane”. Note that changing this setting has no effect on existing files.
Character Encodings
A character encoding is a mapping from a set of characters to their on-disk representation. jEdit can
use any encoding supported by the Java platform.
Buffers in memory are always stored in UTF-16 encoding, which means each character is mapped
to an integer between 0 and 65535. UTF-16 is the native encoding supported by Java, and has a
large enough range of characters to support most modern languages.
When a buffer is loaded, it is converted from its on-disk representation to UTF-16 using a specified
encoding.
The default encoding, used to load files for which no other encoding is specified, can be set in the
Encodings pane of the Utilities> Options dialog box; see the section called “The Encodings Pane”.
Unless you change this setting, it will be your operating system's native encoding, for example
MacRoman on the MacOS, windows-1252 on Windows, and ISO-8859-1 on Unix.
An encoding can be explicitly set when opening a file in the file system browser's
Commands>Encoding menu.
Note that there is no general way to auto-detect the encoding used by a file, however jEdit supports
"encoding detectors", of which there are some provided in the core, and others may be provided by
plugins through the services api. From the encodings option pane the section called “The Encodings
Pane”, you can customize which ones are used, and the order they are tried. Here are some of the
encoding detectors recognized by jEdit:
• BOM: UTF-16 and UTF-8Y files are auto-detected, because they begin with a certain fixed
character sequence. Note that plain UTF-8 does not mandate a specific header, and thus cannot be
auto-detected, unless the file in question is an XML file.
• XML-PI: Encodings used in XML files with an XML PI like the following are auto-detected:
15
Working With Files
<?xml version="1.0" encoding="UTF-8">
• html: Encodings specified in HTML files with a content= attribute in a meta element may be
auto-detected:
<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"
• python: Python has its own way of specifying encoding at the top of a file.
# -*- coding: utf-8 -*• buffer-local-property: Enable buffer-local properties' syntax (see the section called “BufferLocal Properties”) at the top of the file to specify encoding.
#
:encoding=ISO-8859-1:
The encoding that will be used to save the current buffer is shown in the status bar, and can be
changed in the Utilities>Buffer Options dialog box. Note that changing this setting has no effect on
the buffer's contents; if you opened a file with the wrong encoding and got garbage, you will need to
reload it. File>Reload with Encoding is an easy way.
If a file is opened without an explicit encoding specified and it appears in the recent file list, jEdit
will use the encoding last used when working with that file; otherwise the default encoding will be
used.
Commonly Used Encodings
While the world is slowly converging on UTF-8 and UTF-16 encodings for storing text, a wide
range of older encodings are still in widespread use and Java supports most of them.
The simplest character encoding still in use is ASCII, or “American Standard Code for Information
Interchange”. ASCII encodes Latin letters used in English, in addition to numbers and a range
of punctuation characters. Each ASCII character consists of 7 bits, there is a limit of 128 distinct
characters, which makes it unsuitable for anything other than English text. jEdit will load and save
files as ASCII if the US-ASCII encoding is used.
Because ASCII is unsuitable for international use, most operating systems use an 8-bit extension
of ASCII, with the first 128 values mapped to the ASCII characters, and the rest used to encode
accents, umlauts, and various more esoteric used typographical marks. The three major operating
systems all extend ASCII in a different way. Files written by Macintosh programs can be read using
the MacRoman encoding; Windows text files are usually stored as windows-1252. In the Unix
world, the 8859_1 character encoding has found widespread usage.
On Windows, various other encodings, referred to as code pages and identified by number, are used
to store non-English text. The corresponding Java encoding name is windows- followed by the
code page number, for example windows-850.
Many common cross-platform international character sets are also supported; KOI8_R for Russian
text, Big5 and GBK for Chinese, and SJIS for Japanese.
The File System Browser (FSB)
Utilities>File System Browser displays the file system browser. By default, the file system browser
is shown in a floating window. This window can be docked using the commands in its top-left
corner popup menu; see the section called “Window Docking Layouts”.
The FSB can be customized in the Utilities>Options dialog box; see the section called “The File
System Browser Panes”.
16
Working With Files
Navigating the File System
The directory to browse is specified in the Path text field. Clicking the mouse in the text field
automatically selects its contents allowing a new path to be quickly typed in. If a relative path is
entered, it will be resolved relative to the current path. This text field remembers previously entered
strings; see Appendix C, History Text Fields. The same list of previously browsed directories is also
listed in the Utilities>Recent Directories menu; selecting one opens it in the file system browser.
To browse a listed directory, double-click it (or if you have a three-button mouse, you can click the
middle mouse button as well). Alternatively, click the disclosure widget next to a directory to list
its contents in place. To browse higher up in the directory hierarchy, double-click one of the parent
directories in the parent directory list.
Files and directories in the file list are shown in different colors depending on what glob patterns
their names match. The patterns and colors can be customized in the File System Browser>Colors
pane of the Utilities>Options dialog box.
The Path: Text Box can be used to navigate to a specific directory. Environment variables are
expanded here, allowing for both $VARNAME or %VARNAME% syntax.
A+Up is a keyboard shortcut that brings you to the parent directory.
A+Left and A+Right navigate back and forward through the visited directory stacks, in a
Netscape/Konqueror/IE like fashion.
To see a specific set of files only (for example, those whose names end with .java), enter a
glob pattern in the Filter text field. This text fields remembers previously entered strings. See
Appendix D, Glob Patterns for information about glob patterns.
Unopened files can be opened by double-clicking (or by clicking the middle mouse button). Open
files have their names underlined, and can be selected by single-clicking. Holding down Shift
while opening a file will open it in a new view.
Clicking a file or directory with the right mouse button displays a popup menu containing various
commands.
Tip
The file list sorting algorithm used in jEdit handles numbers in file names in an intelligent
manner. For example, a file named section10.xml will be placed after a file named
section5.xml. A conventional letter-by-letter sort would have placed these two files in
the wrong order.
The Tool Bar
The file system browser has a tool bar containing a number of buttons. Each item in the Commands
menu (described below) except Show Hidden Files and Encoding has a corresponding tool bar
button.
The Commands Menu
Clicking the Commands button displays a menu containing the following items:
• Parent Directory - moves up in the directory hierarchy. The Alt+Left arrow keyboard shortcut
achieves the same thing.
• Reload Directory - reloads the file list from disk. F5 does this also.
• Root Directory - on Unix, goes to the root directory (/). On Windows and MacOS X, lists all
mounted drives and network shares. The forward slash (/) achieves this too.
17
Working With Files
• Home Directory - displays your home directory. Keyboard shortcut: ~
• Directory of Current Buffer - displays the directory containing the currently active buffer.
Shortcut: • New File (Ctrl+N) - opens new, empty, buffer in the current directory. The file will not actually
be created on disk until the buffer is saved.
• New Directory - creates a new directory after prompting for the desired name.
• Search in Directory - displays the search and replace dialog box set to search all files in the
current directory. If a file is selected when this command is invoked, its extension becomes the
file name filter for the search; otherwise, the file name filter entered in the browser is used. See
the section called “Search and Replace” for details.
• Show Hidden Files - toggles if hidden files are to be shown in the file list.
• Encoding - a menu for selecting the character encoding to use when opening files. See the section
called “Character Encodings”.
The Plugins Menu
Clicking the Plugins button displays a menu containing plugin commands. For information about
plugins, see Chapter 9, Installing and Using Plugins.
The Favorites Menu
Clicking the Favorites button displays a menu showing all files and directories in the favorites list.
The Add to Favorites item adds the currently selected file to the favorites list. If nothing is selected,
the current directory is added. To remove a file from the favorites, invoke Edit Favorites, which
will show the favorites list in the file system view, then select Delete from the right-click menu of
the entry you want to remove.
Keyboard Shortcuts
Completion behaves differently in file dialogs than in the stand-alone file system browser window.
In the file dialog, keyboard input goes in the file name field by default. Pressing Enter opens
the file or directory path that is either fully or partially entered in the file name field. Typing the
first few characters of a file's name selects that file. If the file name field is empty and nothing is
selected, / lists the root directory on Unix and the list of drives on Windows. There are two handy
abbreviations that may be used in file paths: ~ expands to the home directory, and - expands to the
current buffer's directory.
For example, to open a file /home/slava/jEdit/doc/TODO.txt, you might enter ~/j/d/
to.
In the stand-alone file system browser, keyboard input is handled slightly differently. There is no
file name field, instead shortcuts are active when the file tree has keyboard focus. Additionally,
pressing /, ~ or - always immediately goes to the root, home and current buffer's directory,
respectively.
Reloading From Disk
When a view is brought to the foreground, jEdit checks if any open buffers were modified on disk
by another application. All affected buffers are listed in a dialog box. By default, buffers without
unsaved changes are automatically reloaded. This feature can be disabled, or changed to prompt
18
Working With Files
if files should be reloaded first, in the General pane of the Utilities>Options dialog box; see the
section called “The Global Options Dialog Box”.
File>Reload can be used to reload the current buffer from disk at any other time; a confirmation
dialog box will be displayed first if the buffer has unsaved changes.
File>Reload All discards unsaved changes in all open buffers and reload them from disk, asking for
confirmation first.
Task Monitor, and background I/O tasks
To improve responsiveness and perceived performance, jEdit executes all buffer input/output tasks
asynchronously. Plugins should do the same. When a task such as this is in progress, the status bar
should display the number of running tasks and an icon that spins. If you do not see this, you can
add the widget from the the section called “The Status Bar Pane”.
The Utilities>Troubleshooting> Task Monitor command displays a window with more detailed
status information and progress meters for each task. By default, the Task Monitor is shown in
a floating window. This window can be docked using the commands in its top-left corner popup
menu; see the section called “Window Docking Layouts”. Tasks can be aborted in this window,
however note that aborting a buffer save can result in data loss.
Printing
File>Print (shortcut: C+p) prints the current buffer.
File>Page Setup displays a dialog box for changing your operating system's print settings, such as
margins, page size, print quality, and so on.
The print output can be customized in the Printing pane of the Utilities>Options dialog box; see
the section called “The Printing Pane”. The following settings can be changed:
• The font to use when printing.
• If a header with the file name should be printed on each page.
• If a footer with the page number and current date should be printed on each page.
• If line numbers should be printed.
• If the output should be color or black and white.
• The tab size to use when printing - this will usually be less than the text area tab size, to conserve
space in the printed output.
• If folded regions should be printed.
Closing Files and Exiting jEdit
File>Close (shortcut: C+w) closes the current buffer. If it has unsaved changes, jEdit will ask if they
should be saved first.
File>Close All (shortcut: C+e C+w) closes all buffers. If any buffers have unsaved changes, they
will be listed in a dialog box where they can be saved or discarded. In the dialog box, multiple
buffers to operate on at once can be selected by clicking on them in the list while holding down
Control. After all buffers have been closed, a new untitled buffer is opened.
File>Exit (shortcut: C+q) will completely exit jEdit, prompting if unsaved buffers should be saved
first.
19
Chapter 5. Editing Text
Moving The Caret
The simplest way to move the caret is to click the mouse at the desired location in the text area. The
caret can also be moved using the keyboard.
The LEFT, RIGHT, UP and DOWN keys move the caret in the respective direction, and the
PAGE_UP and PAGE_DOWN keys move the caret up and down one screen-full, respectively.
When pressed once, the HOME key moves the caret to the first non-whitespace character of the
current screen line. Pressing it a second time moves the caret to the beginning of the current buffer
line. Pressing it a third time moves the caret to the first visible line.
The END key behaves in a similar manner, going to the last non-whitespace character of the current
screen line, the end of the current buffer line, and finally to the last visible line.
If soft wrap is disabled, a “screen line” is the same as a “buffer line”. If soft wrap is enabled, a
screen line is a section of a newline-delimited buffer line that fits within the wrap margin width. See
the section called “Wrapping Long Lines”.
C+HOME and C+END move the caret to the beginning and end of the buffer, respectively.
More advanced caret movement is covered in the section called “Working With Words”, the section
called “Working With Lines” and the section called “Working With Paragraphs”.
The Home and End keys
If you prefer more traditional behavior for the HOME and END keys, you can reassign the
respective keyboard shortcuts in the Shortcuts pane of the Utilities>Options; see the section
called “The Shortcuts Pane”.
By default, the shortcuts are assigned as follows:
• HOME is bound to Smart Home.
• END is bound to Smart End.
• S+HOME is bound to Select to Smart Home Position.
• S+END is bound to Select to Smart End Position.
However you can rebind them to anything you want, for example, various combinations of
the following, or indeed any other command or macro:
• Go to Start/End of White Space.
• Go to Start/End of Line.
• Go to Start/End of Buffer.
• Select to Start/End of White Space .
• Select to Start/End of Line.
• Select to Start/End of Buffer.
20
Editing Text
Selecting Text
A selection is a block of text marked for further manipulation. Range selections are equivalent to
selections in most other text editors; they cover text between two points in a buffer. In addition to
the standard text-selection mode, jEdit also allows rectangular selections that cover a rectangular
area (some text editors refer to these as “column selections”). Furthermore, several chunks of text
can be selected and operated on simultaneously.
Range Selection
Dragging the mouse creates a range selection from where the mouse was pressed to where it was
released. Holding down Shift while clicking a location in the buffer will create a selection from
the caret position to the clicked location.
Holding down Shift in addition to a caret movement key (LEFT, UP, HOME, etc) will extend a
selection in the specified direction.
Edit>Select All (shortcut: C+a) selects the entire buffer.
Edit>More Selection>Select None (shortcut: ESCAPE) deactivates the selection.
Rectangular Selection
Dragging with the Control key held down will create a rectangular selection. Holding down
Shift and Control while clicking a location in the buffer will create a rectangular selection
from the caret position to the clicked location.
Alternatively, invoking Edit>More Selection>Rectangular Selection (shortcut: A+\) toggles
rectangular selection mode. In rectangular selection mode, dragging the mouse always creates a
rectangular selection, and keyboard commands that would normally create a range selection create a
rectangular selection instead. A status bar indicator is shown when this mode is enabled.
It is possible to select a rectangle with zero width but non-zero height. This can be used to insert a
new column between two existing columns, for example. Such zero-width selections are shown as a
thin vertical line.
Inserting text into a rectangular selection repeats the text going down as many times as necessary,
and shifts the selection to the right. This makes it behave like a “tall” caret.
Rectangles can be deleted, copied, pasted, and operated on using ordinary editing commands. If
necessary, rectangular selections are automatically filled in with whitespace to maintain alignment.
Rectangular selections can extend beyond the end of a line into “virtual space”. Furthermore, if
keyboard rectangular selection mode is on or if the Control key is being held down, clicking
beyond the end of a line will insert the appropriate amount of whitespace in order to position the
cursor at the clicked location.
Note
Rectangular selections are implemented using character offsets, not absolute screen
positions, so they might not behave as you might expect if a proportional-width font is
being used or if soft wrap is enabled. The text area font can be changed in the Text Area
pane of the Utilities> Options dialog box. For information about soft wrap, see the section
called “Wrapping Long Lines”.
Multiple Selection
Edit>More Selection>Multiple Selection (keyboard shortcut: C+\) turns multiple selection mode
on and off. In multiple selection mode, multiple fragments of text can be selected and operated on
21
Editing Text
simultaneously, and the caret can be moved independently of the selection. The status bar indicates
if multiple selection mode is active; see the section called “The Status Bar”.
Various jEdit commands behave differently with multiple selections:
• Commands that copy text place the contents of each selection, separated by line breaks, in the
specified register.
• Commands that insert (or paste) text replace each selection with the entire text that is being
inserted.
• Commands that filter text (such as Spaces to Tabs, Range Comment, Replace in Selection, and
so on) behave as if each block was selected independently, and the command invoked on each in
turn.
• Line-based commands (such as Shift Indent Left, Shift Indent Right, and Line Comment)
operate on each line that contains at least one selection.
• Caret movement commands that would normally deactivate the selection (such as the arrow keys,
while Shift is not being held down), move the caret, leaving the selection as-is.
• Some older plugins may not support multiple selection at all.
Edit>More Selection>Select None (shortcut: ESCAPE) deactivates the selection containing the
caret, if there is one. Otherwise it deactivates all active selections.
Edit>More Selection>Invert Selection (shortcut: C+e C+i) selects a set of text chunks such that
all text that was formerly part of a selection is now unselected, and all text that wasn't, is selected.
Note
Deactivating multiple selection mode while multiple blocks of text are selected will
leave the selections in place, but you will not be able to add new selections until multiple
selection mode is reactivated.
Keyboard Focus
When the cursor disappears, that means the text area no longer has focus, and when you type, your
keystrokes are probably going somewhere else, such as a dockable. To ensure that the keyboard is
focused in the textarea, you can always use the mouse and click in it, but a more keyboard-friendly
way is preferred when you are just about to start typing anyway. For this reason, a number of jEdit's
actions have a side-effect of focusing on the text area as well. View - Toggle Full Screen is one
example. Some others are listed below:
From the View - Scrolling submenu:
• Scroll and Center Caret
• Scroll to Line
From the View - Docking submenu:
• Toggle Docked Areas
• Close current docking area
In general, jEdit is a keyboard-friendly editor that is also mouse-friendly, so you should never be
forced to use a mouse to do anything.
22
Editing Text
Inserting and Deleting Text
Text entered at the keyboard is inserted into the buffer. In overwrite mode, which can be toggled
by pressing INSERT, one character is deleted from in front of the caret position for every character
that is inserted. The caret is drawn as a horizontal line while overwrite mode is active. The status bar
also indicates if overwrite mode is active; see the section called “The Status Bar” for details.
Inserting text while there is a selection will replace the selection with the inserted text.
When inserting text, the TAB and ENTER keys might not behave entirely like you expect because of
various indentation features; see the section called “Tabbing and Indentation” for details.
The simplest way to delete text is with the BACKSPACE and DELETE keys. If nothing is selected,
they delete the character before or after the caret, respectively. If a selection exists, both delete the
selection.
More advanced deletion commands are described in the section called “Working With Words”, the
section called “Working With Lines” and the section called “Working With Paragraphs”.
Undo and Redo
Edit>Undo (shortcut: C+z) reverses the most recent editing command. For example, this can be
used to restore unintentionally deleted text. More complicated operations, such as a search and
replace, can also be undone.
If you undo too many changes, Edit>Redo (shortcut: C+e C+z) can restore the changes again. For
example, if some text was inserted, Undo will remove it from the buffer. Redo will insert it again.
By default, the last 100 edits is retained; older edits cannot be undone. The maximum number of
undos and whether undos are reset when a buffer is saved can be changed in the Editing pane of the
Utilities> Options dialog box; see the section called “The Editing Pane”.
Working With Words
C+LEFT and C+RIGHT move the caret a word at a time. Holding down Shift in addition to the
above extends the selection a word at a time.
A single word can be selected by double-clicking with the mouse, or using the Edit>More
Selection>Select Word command (shortcut: C+e w). A selection that begins and ends on word
boundaries can be created by double-clicking and dragging.
C+BACKSPACE and C+DELETE delete the word before or after the caret, respectively.
Edit>Complete Word (shortcut: C+b) locates possible completions for the word at the caret, first
by looking in the current edit mode's syntax highlighting keyword list, and then in the current buffer
for words that begin with the word at the caret. This serves as a very basic code completion feature.
If there is only one completion, it will be inserted into the buffer immediately.
If multiple completions were found, the longest common prefix is inserted into the buffer, and a
popup is shown below the caret position listing the completions.
To insert a completion from the list, either select it using the UP and DOWN keys and press ENTER,
press a digit to insert one of the first ten completions (1 is the first completion; 9 is the 9th; 0 is
the 10th), or click the desired completion with the mouse. To close the popup without inserting a
completion, press ESCAPE.
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Editing Text
Typing while the popup is visible will automatically update the popup and narrow the set of
completions as necessary.
The default word completion uses the visible buffers (buffers being shown in an EditPane) to find
completions. The set of possible words can be expanded by enabling the Global Options - Text
Area - Complete words from all open buffers option. Setting this option will use all open buffers
to search for possible completions. Note, this can degrade completion performance if many buffers
are open.
Edit>Word Count displays a dialog box with the number of characters, words and lines in the
current buffer.
What's a Word?
The default behavior of the C+LEFT, C+RIGHT, C+BACKSPACE and C+DELETE commands
is to stop both at the beginning and the end of each word. Normally, a word is a sequence of
alphanumerics, but you can add other characters as part of what jEdit considers to be a 'word', set
on a global or mode basis from Global Options - Editing - Extra Word Characters. In addition,
this behavior can be changed by remapping these keystrokes to alternative actions whose names end
with (Eat Whitespace) in the Shortcuts pane of the Utilities>Options dialog box; see the section
called “The Shortcuts Pane”.
Working With Lines
An entire line can be selected by triple-clicking with the mouse, or using the Edit>More
Selection>Select Line command (shortcut: C+e l). A selection that begins and ends on line
boundaries can be created by triple-clicking and dragging.
Edit>Go to Line (shortcut: C+l) prompts for a line number and moves the caret there. A relative
offset can be used here, if it is prefixed by a + or a - sign. So for example -5 moves the caret up by
5 lines.
Edit>More Selection>Select Line Range (shortcut: C+e C+l) prompts for two line numbers and
selects all text between them.
Edit>Text>Delete Line (shortcut: C+d) deletes the current line.
Edit>Text>Delete to Start Of Line (shortcut: CS+BACK_SPACE) deletes all text from the start of
the current line to the caret.
Edit>Text>Delete to End Of Line (shortcut: CS+DELETE) deletes all text from the caret to the
end of the current line.
Edit>Text>Join Lines (shortcut: C+j) removes any whitespace from the start of the next line and
joins it with the current line. The caret is moved to the position where the two lines were joined. For
example, if you invoke Join Lines with the caret on the first line of the following Java code:
new Widget(Foo
.createDefaultFoo());
It will be changed to:
new Widget(Foo.createDefaultFoo());
Working With Paragraphs
As far as jEdit is concerned, “paragraphs” are delimited by double newlines. This is also how TeX
defines a paragraph. Note that jEdit doesn't parse HTML files for “<P>” tags, nor does it support
paragraphs delimited only by a leading indent.
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Editing Text
C+UP and C+DOWN move the caret to the previous and next paragraph, respectively. Holding down
Shift in addition to the above extends the selection a paragraph at a time.
Edit>More Selection>Select Paragraph (shortcut: C+e p) selects the paragraph containing the
caret.
Edit>Text>Format Paragraph (shortcut: C+e f) splits and joins lines in the current selection
to make it fit within the wrap column position. If nothing is selected, the paragraph containing the
caret is formatted instead. See the section called “Wrapping Long Lines” for information about
word wrap and changing the wrap column.
Edit>Text>Delete Paragraph (shortcut: C+e d) deletes the paragraph containing the caret.
Wrapping Long Lines
The word wrap feature splits lines at word boundaries in order to fit text within a specified wrap
margin. A word boundary, for the purposes of word wrap, means whitespace. Long lines without
whitespace are currently not wrapped by jEdit. The wrap margin position is indicated in the text
are as a faint blue vertical line. There are two “wrap modes”, “soft” and “hard”; they are described
below. The current wrap mode is shown in the status bar; see the section called “The Status Bar”.
The wrap mode can be changed in one of the following ways:
• On a global or mode-specific basis in the Editing pane of the Utilities> Options dialog box. See
the section called “The Editing Pane”.
• In the current buffer for the duration of the editing session,
• By clicking the status bar indicator.
• In the Utilities>Buffer Options dialog box. See the section called “The Buffer Options Dialog
Box”.
• From the keyboard, if a keyboard shortcut has been assigned to the Built-in Command for
Toggle Word Wrap in the Shortcuts pane of Global Options. By default, this command does
not have a keyboard shortcut, or appear in any menu.
• In the current buffer for future editing sessions by placing the following in one of the first or last
10 lines of the buffer, where mode is either “none”, “soft” or “hard”, and column is the desired
wrap margin:
:wrap=mode:maxLineLen=column:
Soft Wrap
In soft wrap mode, lines are automatically wrapped when displayed on screen. Newlines are not
inserted at the wrap positions, and the wrapping is automatically updated when text is inserted or
removed.
If the margin is set to 0, then the width of the text area window is used to determine where to wrap
lines.
If end of line markers are enabled in the Text Area pane of the Utilities>Options dialog box, a
colon (“:”) is painted at the end of wrapped lines. See the section called “The Text Area Pane”.
Hard Wrap
In hard wrap mode, inserting text at the end of a line will automatically break the line if it extends
beyond the wrap margin. Inserting or removing text in the middle of a line has no effect, however
25
Editing Text
text can be re-wrapped using the Edit>Text>Format Paragraph command. See the section called
“Working With Paragraphs”.
Hard wrap is implemented using character offsets, not screen positions, so it might not behave like
you expect if a proportional-width font is being used. The text area font can be changed in the Text
Area pane of the Utilities>Options dialog box.
Scrolling
If you have a mouse with a scroll wheel, you can use the wheel to scroll up and down in the text
area. Various modifier keys change the action of the wheel:
• Shift - moves the horizontal scrollbar. time.
• Control - scrolls a single line at a time.
• Alt - moves the caret up and down instead of scrolling.
• CTRL+SHIFT - scroll a page at a time.
• Alt+Shift - extends the selection up and down instead of scrolling.
Keyboard commands for scrolling the text area are also available.
View>Scrolling>Scroll to Current Line (shortcut: C+e C+j) scrolls the text area in order to
make the caret visible, if necessary. It does nothing if the caret is already visible.
View>Scrolling>Center Caret on Screen (shortcut: C+e C+n) moves the caret to the line in the
middle of the screen.
View>Scrolling>Line Scroll Up (shortcut: C+QUOTE) scrolls the text area up by one line.
View>Scrolling>Line Scroll Down (shortcut: C+SLASH) scrolls the text area down by one line.
View>Scrolling>Page Scroll Up (shortcut: A+QUOTE) scrolls the text area up by one screenful.
View>Scrolling>Page Scroll Down (shortcut: A+SLASH) scrolls the text area down by one
screenful.
The above scrolling commands differ from the caret movement commands in that they don't actually
move the caret; they just change the scroll bar position.
Transferring Text
jEdit provides a rich set of commands for moving and copying text. Commands are provided for
moving chunks of text from buffers to registers and vice-versa. A register is a holding area for an
arbitrary length of text, with a single-character name. Most other programs can only transfer text
to and from the system clipboard; in jEdit, the system clipboard is just another register, with the
special name $.
The Clipboard
jEdit offers the usual text transfer operations, that operate on the $ register.
Edit>Cut (shortcut: C+x) places the selected text in the clipboard and removes it from the buffer.
Edit>Copy (shortcut: C+c) places the selected text in the clipboard and leaves it in the buffer.
Edit>Paste (shortcut: C+v) inserts the clipboard contents in place of the selection (or at the caret
position, if there is no selection).
26
Editing Text
The Cut and Copy commands replace the old clipboard contents with the selected text. There are
two alternative commands which add the selection at the end of the existing clipboard contents,
instead of replacing it.
Edit>More Clipboard>Cut Append (shortcut: C+e C+u) appends the selected text to the
clipboard, then removes it from the buffer. After this command has been invoked, the clipboard will
consist of the former clipboard contents, followed by a newline, followed by the selected text.
Edit>More Clipboard>Copy Append (shortcut: C+e C+a) is the same as Cut Append except it
does not remove the selection from the buffer.
Quick Copy
The quick copy feature is usually found in Unix text editors. Quick copy is disabled by default, but
it can be enabled in the Mouse pane of the Utilities>Options dialog box.
The quick copy feature is accessed using the middle mouse button. If you do not have a three-button
mouse, then either Alt-click (on Windows and Unix) or Option-click (on MacOS X). The quick
copy feature enables the following behavior:
• Clicking the middle mouse button in the text area inserts the most recently selected text at the
clicked location. If you only have a two-button mouse, you can click the left mouse button while
holding down Alt instead of middle-clicking.
• Dragging with the middle mouse button creates a selection without moving the caret. As soon as
the mouse button is released, the selected text is inserted at the caret position and the selection is
deactivated. A message is shown in the status bar while text is being selected to remind you that
this is not an ordinary selection.
• Holding down Shift while clicking the middle mouse button will duplicate text between the
caret and the clicked location.
• Holding down Control while clicking the middle mouse button on a bracket will insert all text
in that bracket's scope at the caret position.
The most recently selected text is stored in the % register.
If jEdit is being run under Java 2 version 1.4 on Unix, you will be able to transfer text with other
X Windows applications using the quick copy feature. On other platforms and Java versions, the
contents of the quick copy register are only accessible from within jEdit.
General Register Commands
These commands require more keystrokes than the two methods shown above, but they can operate
on any register, allowing an arbitrary number of text chunks to be retained at a time.
Each command prompts for a single-character register name to be entered after being invoked.
Pressing ESCAPE instead of specifying a register name cancels the operation.
Note that the content of registers other than the clipboard and quick copy register are automatically
saved between jEdit sessions.
Edit>More Clipboard>Cut to Register (shortcut: C+r C+x key) stores the selected text in the
specified register, removing it from the buffer.
Edit>More Clipboard>Copy to Register (shortcut: C+r C+c key) stores the selected text in the
specified register, leaving it in the buffer.
Edit>More Clipboard>Cut Append to Register (shortcut: C+r C+u key) adds the selected text
to the existing contents of the specified register, and removes it from the buffer.
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Editing Text
Edit>More Clipboard>Copy Append to Register (shortcut: C+r C+a key) adds the selected
text to the existing contents of the specified register, without removing it from the buffer.
Edit>More Clipboard>Paste from Register (shortcut: C+r C+v key) replaces the selection
with the contents of the specified register.
The following three commands display dialog boxes instead of prompting for a register name.
Edit>More Clipboard>Paste Previous (shortcut: C+e C+v) displays a dialog box listing the 20
most recently copied and pasted text strings.
Edit>More Clipboard>Paste Deleted (shortcut: C+e C+y) is not really a register command; it
displays a dialog box listing the 20 most recently deleted text strings.
Edit>More Clipboard>View Registers displays a dialog box for viewing register contents,
including the clipboard and the quick copy.
Markers
MarkerSets
The MarkerSets plugin is a replacement for the built-in Markers feature of jEdit. Markers
saved with MarkerSets properly update when lines are added or removed from a buffer.
Furthermore, you can see markers from multiple files in the Marker Sets dockable. We
recommend you use that instead of the built-in Markers.
A marker is a pointer to a specific location within a buffer, which may or may not have
a single-character shortcut associated with it. Markers are persistent; they are saved to
.filename.marks, where filename is the name of the buffer. (The dot prefix makes the
markers file hidden on Unix systems.) Marker saving can be disabled in the General pane of the
Utilities>Options dialog box; see the section called “The General Pane”.
Markers>Add/Remove Marker (shortcut: C+e C+m) adds a marker without a shortcut pointing to
the current line. If a marker is already set on the current line, the marker is removed instead. If text
is selected, markers are added to the first and last line of each selection.
Markers are listed in the Markers menu; selecting a marker from this menu will move the caret to
its location.
Markers>Go to Previous Marker (shortcut: C+e C+COMMA) goes to the marker immediately
before the caret position.
Markers>Go to Next Marker (shortcut: C+e C+PERIOD) goes to the marker immediately after
the caret position.
Markers>Remove All Markers removes all markers set in the current buffer.
Markers with shortcuts allow for quicker keyboard-based navigation. The following commands
all prompt for a single-character shortcut when invoked. Pressing ESCAPE instead of specifying a
shortcut will cancel the operation.
Markers>Add Marker With Shortcut (shortcut: C+t key) adds a marker with the specified
shortcut. If marker with that shortcut already exists, it will remain in the buffer but lose its shortcut.
Markers>Go to Marker (shortcut: C+y key) moves the caret to the location of the marker with
the specified shortcut.
Markers>Select to Marker (shortcut: C+u key) creates a selection from the caret location to the
marker with the specified shortcut.
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Editing Text
Markers>Swap Caret and Marker (shortcut: C+k key) moves the caret to the location of the
marker with the specified shortcut, and moves the marker to the former caret position. Invoke this
command multiple times to flip between two locations in the buffer.
Lines which contain markers are indicated in the gutter with a highlight. Moving the mouse over
the highlight displays a tool tip showing the marker's shortcut, if it has one. See the section called
“Interface Overview” for information about the gutter.
Search and Replace
Searching For Text
Search>Find (shortcut: C+f) displays the search and replace dialog box.
The search string can be entered in the Search for text field. This text field remembers previously
entered strings; see Appendix C, History Text Fields for details.
If text was selected in the text area and the selection does not span a line break, the selected text
becomes the default search string.
If the selection spans a line break, the Search in Selection and HyperSearch buttons will be preselected, and the search string field will be initially blank. (See the section called “HyperSearch” for
information about the HyperSearch feature.)
Selecting the Ignore case check box makes the search case insensitive - for example, searching for
“Hello” will match “hello”, “HELLO” and “HeLlO”.
After selecting the Whole word check box, searching respects the Extra word characters setting
from the editing options for recognizing words.
To search for special characters (such as newlines or non-printable characters), inexact sequences
of text, or strings that span multiple lines, we use Regular Expressions. Selecting the Regular
expressions check box allows special characters to be used in the search string. Regular expression
syntax is described in Appendix E, Regular Expressions. If you use (groups) in the search field, you
back-reference them with $1 through $9 in the replace field.
The Backward and Forward buttons specify the search direction. Note that regular expressions can
only be used when searching in a forward direction.
Clicking Find will locate the next occurrence of the search string (or previous occurrence, if
searching backwards). If the Keep dialog check box is selected, the dialog box will remain open
after the search string has been located; otherwise, it will close.
If no occurrences could be found and the Auto wrap check box is selected, the search will
automatically restart from the beginning of the buffer (or the end, if searching backwards). If Auto
wrap is not selected, a confirmation dialog box is shown before restarting the search.
Search>Find Next (shortcut: C+g) locates the next occurrence of the most recent search string
without displaying the search and replace dialog box.
Search>Find Previous (shortcut: C+h) locates the previous occurrence of the most recent search
string without displaying the search and replace dialog box.
Replacing Text
The replace string text field of the search dialog remembers previously entered strings; see
Appendix C, History Text Fields for details.
29
Editing Text
Clicking Replace & Find will perform a replacement in the current selection and locate the next
occurrence of the search string. Clicking Replace All will replace all occurrences of the search
string with the replacement string in the current search scope (which is either the selection, the
current buffer, or a set of buffers, as specified in the search and replace dialog box).
Occurrences of the search string can be replaced with either a replacement string, or the return value
of a BeanShell script snippet. Two radio buttons in the search and replace dialog box select between
the two replacement modes, which are described in detail below.
Text Replace
If the Text button is selected, the search string is simply replaced with the replacement string.
If regular expressions are enabled, positional parameters ($0, $1, $2, and so on) can be used to
insert the contents of matched subexpressions in the replacement string; see Appendix E, Regular
Expressions for more information.
If the search is case-insensitive, jEdit attempts to modify the case of the replacement string to match
that of the particular instance of the search string being replaced. For example, searching for “label”
and replacing it with “text”, will perform the following replacements:
• “String label” would become “String text”
• “setLabel” would become “setText”
• “DEFAULT_LABEL” would become “DEFAULT_TEXT”
BeanShell Replace
In BeanShell replacement mode, the search string is replaced with the return value of a BeanShell
snippet. If you want to use multiple line snippet, enclose your BeanShell in braces. The following
predefined variables can be referenced in the snippet:
• _0 -- the text to be replaced
• _1 - _9 -- if regular expressions are enabled, these contain the values of matched subexpressions.
BeanShell syntax and features are covered in great detail in Part III, “Writing Macros”, but here are
some examples:
To replace each occurrence of “Windows” with “Linux”, and each occurrence of “Linux” with
“Windows”, search for the following regular expression:
(Windows|Linux)
Replacing it with the following BeanShell snippet:
_1.equals("Windows") ? "Linux" : "Windows"
To convert all HTML tags to lower case, search for the following regular expression:
<\S+
Replacing it with the following BeanShell snippet:
_0.toLowerCase()
To replace arithmetic expressions contained in curly braces with the result of evaluating the
expression, search for the following regular expression:
\{(.+?)\}
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Editing Text
Replacing it with the following BeanShell snippet:
eval(_1)
These examples only scratch the surface; the possibilities are endless.
HyperSearch
If the HyperSearch check box in the search and replace dialog box is selected, clicking Find lists
all occurrences of the search string, instead of locating the next match.
By default, HyperSearch results are shown in a floating window. This window can be docked using
the commands in its top-left corner popup menu; see the section called “Window Docking Layouts”.
If the Multiple results check box is selected in the results window, past search results are retained.
Running searches can be stopped in the Utilities>Troubleshooting>I/O Progress Monitor dialog
box.
Once the results are shown in the Hypersearch dockable, you can left-click on a result to jump to the
position, or right-click to see some "hidden actions". From the top tree-node, for example, you can
Redo Hypersearch, and Copy to Clipboard.
Multiple File Search
Search and replace commands can be performed over an arbitrary set of files in one step. The set of
files to search is selected with a set of buttons in the search dialog box.
If the Current buffer button is selected, only the current buffer is searched. This is the default
behavior.
If the All buffers button is selected, all open buffers whose names match the glob pattern entered
in the Filter text field will be searched. See Appendix D, Glob Patterns for more information about
glob patterns.
If the Directory radio button is selected, all files contained in the specified directory whose names
match the glob will be searched. The directory to search in can either be entered in the Directory
text field, or chosen in a file selector dialog box by clicking the Choose button next to the field. If
the Search subdirectories check box is selected, all subdirectories of the specified directory will
also be searched. Keep in mind that searching through directories containing many files can take a
long time.
The Directory and Filter text fields remember previously entered strings; see Appendix C, History
Text Fields for details.
When the search and replace dialog box is opened, the directory and file name filter fields are set to
their previous values. They can be set to match the current buffer's directory and file name extension
by clicking Synchronize.
Note that clicking the All Buffers or Directory radio buttons also selects the HyperSearch check
box since that is what you would want, most of the time. However, the HyperSearch check box can
be unchecked, for stepping through search results in multiple files one at a time.
Two convenience commands are provided for performing multiple file searches.
Search>Search in Open Buffers (shortcut: C+e C+b) displays the search dialog box and selects
the All buffers button.
Search>Search in Directory (shortcut: C+e C+d) displays the search dialog box and selects the
Directory button.
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Editing Text
The Search Bar
The search bar feature provides a convenient way to search in the current buffer without opening the
search dialog box. The search bar does not support replacement or multiple file search. Previously
entered strings can be recalled in the search bar with the Up and Down arrow keys; see Appendix C,
History Text Fields.
By default, the search bar remains hidden until one of the quick search commands (described
below) is invoked; however you can choose to have it always visible in the View pane of the
Utilities>Options dialog box; see the section called “The View Pane”.
Search>Incremental Search Bar (shortcut: C+COMMA) displays the search bar if necessary, and
gives it keyboard focus.
Search>Incremental Search for Word (shortcut: A+COMMA) behaves like the above command
except it places the word at the caret in the search string field. If this command is invoked while
there is a selection, the selection is placed in the search string field instead.
Unless the HyperSearch check box is selected, the search bar will perform an incremental search.
In incremental search mode, the first occurrence of the search string is located in the current buffer
as it is being typed. Pressing ENTER and S+ENTER searches for the next and previous occurrence,
respectively. Once the desired occurrence has been located, pressing ESCAPE returns keyboard
focus to the text area. Unless the search bar is set to be always visible (see above), pressing ESCAPE
will also hide the search bar.
Note
Incremental searches cannot be not recorded in macros. If your macro needs to perform
a search, use the search and replace dialog box instead. See Chapter 8, Using Macros for
information about macros.
Search>HyperSearch Bar (shortcut: C+PERIOD) displays the search bar if necessary, gives it
keyboard focus, and selects the HyperSearch check box. If this command is invoked while there is
a selection, the selected text will be searched for immediately and the search bar will not be shown.
If the HyperSearch check box is selected, pressing Enter in the search string field will perform a
HyperSearch in the current buffer.
Search>HyperSearch for Word (shortcut: A+PERIOD) performs a HyperSearch for the word at
the caret. This command does not show the search bar or give it keyboard focus.
32
Chapter 6. Editing Source Code
Edit Modes
An edit mode specifies syntax highlighting rules, auto indent behavior, and various other
customizations for editing a certain file type. This section only covers using existing edit modes;
information about writing your own can be found in Part II, “Writing Edit Modes”.
When a file is opened, jEdit first checks the file name against a list of known patterns. For example,
files whose names end with .c are opened with C mode, and files named Makefile are opened
with Makefile mode. If a suitable match based on file name cannot be found, jEdit checks the first
line of the file. For example, files whose first line is #!/bin/sh are opened with shell script
mode.
Mode Selection
File name and first line matching is done using glob patterns similar to those used in Unix shells.
Glob patterns associated with edit modes can be changed in the Editing pane of the Utilities>
Options dialog box. Note that the glob patterns must match the file name or first line exactly; so
to match files whose first line contains begin, you must use a first line glob of *begin*. See
Appendix D, Glob Patterns for a description of glob pattern syntax.
The default edit mode for files which do not match any pattern can be set in the Editing pane as
well.
The edit mode can be specified manually as well. The current buffer's edit mode can be set on a onetime basis in the Utilities>Buffer Options dialog box; see the section called “The Buffer Options
Dialog Box”. To set a buffer's edit mode for future editing sessions, place the following in one of
the first or last 10 lines of the buffer, where edit mode is the name of the desired edit mode:
:mode=edit mode:
Syntax Highlighting
Syntax highlighting is the display of programming language tokens using different fonts and colors.
This makes code easier to follow and errors such as misplaced quotes easier to spot. All edit modes
except for the plain text mode perform some kind of syntax highlighting.
The colors and styles used to highlight syntax tokens can be changed in the Syntax Highlighting
pane of the Utilities> Options dialog box; see the section called “The Syntax Highlighting Pane”.
Tabbing and Indentation
jEdit makes a distinction between the tab width, which is is used when displaying hard tab
characters, and the indent width, which is used when a level of indent is to be added or removed, for
example by mode-specific auto indent routines. Both can be changed in one of several ways:
• On a global or mode-specific basis in the Editing pane of the the Utilities> Options dialog box.
See the section called “The Editing Pane”.
• In the current buffer for the duration of the editing session in the Utilities>Buffer Options dialog
box. See the section called “The Buffer Options Dialog Box”.
• In the current buffer for future editing sessions by placing the following in one of the first or last
10 lines of the buffer, where n is the desired tab width, and m is the desired indent width:
:tabSize=n:indentSize=m:
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Editing Source Code
Edit>Indent>Shift Indent Left (shortcut: S+TAB or A+LEFT) removes one level of indent from
each selected line, or the current line if there is no selection.
Edit>Indent>Shift Indent Right (shortcut: A+RIGHT) adds one level of indent to each selected
line, or the current line if there is no selection. Pressing Tab while a multi-line selection is active
has the same effect.
Edit>Indent>Remove Trailing Whitespace (shortcut: C+e r) removes all whitespace from the
end of each selected line, or the current line if there is no selection.
Soft Tabs
Files containing hard tab characters may look less than ideal if the default tab size is changed, so
some people prefer using multiple space characters instead of hard tabs to indent code.
This feature is known as soft tabs. Soft tabs can be enabled or disabled in one of several ways:
• On a global or mode-specific basis in the Editing pane of the Utilities> Options dialog box. See
the section called “The Editing Pane”.
• In the current buffer for the duration of the editing session in the Utilities>Buffer Options dialog
box. See the section called “The Buffer Options Dialog Box”.
• In the current buffer for future editing sessions by placing the following in one of the first or last
10 lines of the buffer, where flag is either “true” or “false”:
:noTabs=flag:
Changing the soft tabs setting has no effect on existing tab characters; it only affects subsequentlyinserted tabs.
Edit>Indent>Spaces to Tabs converts soft tabs to hard tabs in the current selection, or the entire
buffer if nothing is selected.
Edit>Indent>Tabs to Spaces converts hard tabs to soft tabs in the current selection, or the entire
buffer if nothing is selected.
Elastic Tabstops
Elastic tabstops are an alternative way to handle tabstops. Elastic tabstops differ from traditional
fixed tabstops because columns in lines above and below the "cell" that is being changed are always
kept aligned. As the width of text before a tab character changes, the tabstops on adjacent lines are
also changed to fit the widest piece of text in that column. It provides certain explicit benefits like
it saves time spent on arranging the code and works seemlessly with variable width fonts.But at the
same time it can make the code look unorganized on editors that do not support elastic tabstops.
This feature is known as elastic tabstops. Elastic tabstops can be enabled or disabled in one of
several ways:
• On a global or mode-specific basis in the Editing pane of the Utilities>Options dialog box. See
the section called “The Editing Pane”.
• In the current buffer for the duration of the editing session in the Utilities>Buffer Options dialog
box. See the section called “The Buffer Options Dialog Box”.
• In the current buffer for future editing sessions by placing the following in one of the first or last
10 lines of the buffer, where flag is either “true” or “false”:
:elasticTabstops=flag:
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Editing Source Code
Note that this feature does not work with soft tabs. where tabs are emulated as spaces
Automatic Indent
The auto indent feature inserts the appropriate number of tabs or spaces at the beginning of a
line. There are three different indentation schemes to choose from: “full”, “simple”, and “none”.
The scheme can be chosen on a global or per-edit mode basis using the Editing pane of the
Utilities>Options dialog. It can also be changed for a specific buffer using the Buffer Options
dialog, or with a buffer-local property. (see the section called “Buffer-Local Properties”)
Automatic Indent Scheme: full
In this default scheme, the amount of indentation inserted is mode-specific. In most edit modes,
the indent of the previous line is simply copied over. However, in C-like languages (C, C++, Java,
JavaScript), curly brackets and language statements are taken into account and indent is added and
removed as necessary.
The automatic indentation can be triggered by: pressing ENTER (this will by default only affect
the indentation of the new line), pressing TAB at the beginning of, or inside the leading whitespace
of a line, entering one the bracket characters defined in the edit mode, pressing one of the
electricKeys for the current edit mode (more details in the section called “The PROPS Tag”),
or when causing a hard wrap (see the section called “Wrapping Long Lines”).
No matter what automatic indentation scheme is currently active, Edit > Indent > Indent Selected
Lines (shortcut: C+i) indents all selected lines, or the current line if there is no selection, as if in the
“full” scheme.
Electric keys
Electric keys cause reapplying of the indentation rules to the current line. Thanks to the electric keys
the following code fragments are indented properly on-line:
• Java, C: brackets. If indenting brackets are defined for the language, they are implicitly
considered electric keys. Thus a closing bracket is placed in its correct position immediately after
being typed.
• Java, C: labels. Labels end with a colon and the colon is included in electric keys for these
languages. With pressing the colon, the line is reindented and the labels are indented a level to the
left.
• Basic: endif. Here f letter is an electric key, that makes the line indented to the left.
In jEdit 4 electric keys worked unconditionally. As of jEdit 5 they trigger reindentation only if the
indentation of the line, before pressing a key, is the same as jEdit would indent it using its rules.
This allows for specifying more electric keys in mode files, because they don't cause unwanted
indentation like they did before. Electric keys including all letters seem to be good solution for
basic-like languages.
Automatic Indent Scheme: simple
In this simplified automatic-indentation scheme, only two actions trigger an indentation: pressing
ENTER, or causing a hard wrap. Only the new line will be indented, and the amount of indentation
will be the same as the previously line.
Automatic Indent Scheme: none
In this automatic indentation scheme, no actions in the text area will trigger a reindentation, and all
lines start completely unindented.
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Editing Source Code
Further customization of automatic indentation
The behavior of the ENTER and TAB keys can be configured in the Shortcuts pane of the
Utilities>Options dialog. box, just as with any other key. The ENTER key can be bound to one of
the following, or indeed any other command or macro:
• Insert Newline.
• Insert Newline and Indent, which is the default. This is equivalent to Insert Newline when
using the indentation scheme “none”.
The TAB can be bound to one of the following, or again, any other command or macro:
• Insert Tab.
• Insert Tab or Indent, which is the default. This is equivalent to Insert Tab when not using the
“full” automatic indentation scheme.
• Indent Selected Lines. This binding will not respect the selected auto indentation scheme.
See the section called “The Shortcuts Pane” for details.
To insert a literal tab or newline without performing indentation, prefix the tab or newline with C+e
v. For example, to create a new line without any indentation, type C+e v ENTER.
Commenting Out Code
Most programming and markup languages support the notion of “comments”, or regions of code
which are ignored by the compiler/interpreter. jEdit has commands which make inserting comments
more convenient.
Comment strings are mode-specific, and some in some modes such as HTML different parts of a
buffer can have different comment strings. For example, in HTML files, different comment strings
are used for HTML text and inline JavaScript.
Edit>Source Code>Range Comment (shortcut: C+e C+c) encloses the selection with comment
start and end strings, for example /* and */ in Java mode.
Edit>Source Code>Line Comment (shortcut: C+e C+k) inserts the line comment string, for
example // in Java mode, at the start of each selected line.
Toggling Comments
You might be looking for the actions Toggle Line Comment or Toggle Range Comment.
They are available from the TextTools plugin, not jEdit core.
Bracket Matching
Misplaced and unmatched brackets are one of the most common syntax errors encountered when
writing code. jEdit has several features to make brackets easier to deal with.
Positioning the caret immediately after a bracket will highlight the corresponding closing or opening
bracket (assuming it is visible), and draw a scope indicator in the gutter. If the highlighted bracket is
not visible, the text of the matching line will be shown in the status bar. If the matching line consists
of only whitespace and the bracket itself, the previous line is shown instead. This feature is very
useful when your code is indented as follows, with braces on their own lines:
public void someMethod()
{
if(isOK)
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Editing Source Code
{
doSomething();
}
}
Invoking Edit>Source>Go to Matching Bracket (shortcut: C+]) or clicking the scope indicator in
the gutter moves the caret to the matching bracket.
Edit>Source>Select Code Block (shortcut: C+[) selects all text between the closest two brackets
surrounding the caret.
Holding down Control while clicking the scope indicator in the gutter or a bracket in the text area
will select all text between the two matching brackets.
Edit>Source>Go to Previous Bracket (shortcut: C+e C+[) moves the caret to the previous
opening bracket.
Edit>Source>Go to Next Bracket (shortcut: C+e C+]) moves the caret to the next closing
bracket.
Bracket highlighting in the text area and bracket scope display in the gutter can be customized in
the Text Area and Gutter panes of the Utilities>Options dialog box; see the section called “The
Global Options Dialog Box”.
Tip
jEdit's bracket matching algorithm only checks syntax tokens with the same type as the
original bracket, so for example unmatched brackets inside string literals and comments
will be skipped when matching brackets that are part of program syntax.
Abbreviations
Abbreviations are invoked by typing a couple of letters and then issuing the Edit>Expand
Abbreviation (keyboard shortcut: C+;), which takes the word before the caret as the abbreviation
name. If that particular abbreviation was not yet set, a dialog will pop up, and you can enter the
text to insert before and after the caret. After the abbreviation is created, it can be viewed or edited
from the Abbreviations pane of the Utilities>Options dialog box; see the section called “The
Abbreviations Pane”.
Using abbreviations reduces the time spent typing long but commonly used strings. For example,
in Java mode, the abbreviation “sout” is defined to expand to “System.out.println()”, so to insert
“System.out.println()” in a Java buffer, you only need to type “sout” followed by C+;. An
abbreviation can either be global, in which case it can be used in all edit modes, or specific to a
single mode.
The Java, VHDL. XML and XSL edit modes include some pre-defined abbreviations you might find
useful. Other modes do not have any abbreviations defined by default.
Automatic abbreviation expansion can be enabled in the Abbreviations pane of the
Utilities>Options dialog box. If enabled, pressing the space bar after entering an abbreviation will
automatically expand it.
If automatic expansion is enabled, a space can be inserted without expanding the word before the
caret by pressing Control+E V Space.
Positional Parameters
Positional parameters are an advanced feature that make abbreviations much more useful. The best
way to describe them is with an example.
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Editing Source Code
Java mode defines an abbreviation “F” that is set to expand to the following:
for(int $1 = 0; $1 < $2; $1++)
Expanding F#j#array.length# will insert the following text into the buffer:
for(int j = 0; j < array.length; j++)
Expansions can contain up to nine positional parameters. Note that a trailing hash character (“#”)
must be entered when expanding an abbreviation with parameters.
If you do not specify the correct number of positional parameters when expanding an abbreviation,
any missing parameters will be blank in the expansion, and extra parameters will be ignored. A
status bar message will be shown stating the required number of parameters.
Folding
Program source code and other structured text files can be thought of as containing a hierarchy of
sections, which themselves might contain sub-sections. The folding feature lets you selectively
hide and show these sections, replacing hidden ones with a single line that serves as an “overview”
of that section. Folding is disabled by default. To enable it, you must choose one of the available
folding modes.
“Indent” mode creates folds based on a line's leading whitespace; the more leading whitespace a
block of text has, the further down it is in the hierarchy. For example:
This is a section
This is a sub-section
This is another sub-section
This is a sub-sub-section
Another top-level section
“Explicit” mode folds away blocks of text surrounded with “{{{” and “}}}”. For example:
{{{ The first line of a fold.
When this fold is collapsed, only the above line will be visible.
{{{ A sub-section.
With text inside it.
}}}
{{{ Another sub-section.
}}}
}}}
Both modes have distinct advantages and disadvantages; indent folding requires no changes to be
made to a buffer's text and does a decent job with most program source. Explicit folding requires
“fold markers” to be inserted into the text, but is more flexible in exactly what to fold away.
Some plugins might add additional folding modes; see Chapter 9, Installing and Using Plugins for
information about plugins.
Folding can be enabled in one of several ways:
• On a global or mode-specific basis in the Editing pane of the Utilities> Options dialog box. See
the section called “The Editing Pane”.
• In the current buffer for the duration of the editing session in the Utilities>Buffer Options dialog
box. See the section called “The Buffer Options Dialog Box”.
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Editing Source Code
• In the current buffer for future editing sessions by placing the following in the first or last 10 lines
of a buffer, where mode is either “indent”, “explicit”, or the name of a plugin folding mode:
:folding=mode:
Warning
When using indent folding, portions of the buffer may become inaccessible if you change
the leading indent of the first line of a collapsed fold. If you experience this, you can use
the Expand All Folds command to make the text visible again.
Collapsing and Expanding Folds
The first line of each fold has a triangle drawn next to it in the gutter (see the section called
“Interface Overview” for more information about the gutter). The triangle points toward the line
when the fold is collapsed, and downward when the fold is expanded. Clicking the triangle collapses
and expands the fold. To expand all sub-folds as well, hold down the Shift while clicking.
The first line of a collapsed fold is drawn with a background color that depends on the fold level,
and the number of lines in the fold is shown to the right of the line's text.
Folds can also be collapsed and expanded using menu item commands and keyboard shortcuts.
Folding>Collapse Fold (shortcut: A+BACK_SPACE) collapses the fold containing the caret.
Folding>Expand Fold One Level (shortcut: A+ENTER) expands the fold containing the caret.
Nested folds will remain collapsed, and the caret will be positioned on the first nested fold (if any).
Folding>Expand Fold Fully (shortcut: AS+ENTER) expands the fold containing the caret, also
expanding any nested folds.
Folding>Collapse All Folds (shortcut: C+e c) collapses all folds in the buffer.
Folding>Expand All Folds (shortcut: C+e x) expands all folds in the buffer.
Navigating Around With Folds
Folding>Go to Parent Fold (shortcut: C+e u) moves the caret to the fold containing the one at the
caret position.
Folding>Go to Previous Fold (shortcut: A+UP) moves the caret to the fold immediately before the
caret position.
Folding>Go to Next Fold (shortcut: A+DOWN) moves the caret to the fold immediately after the
caret position.
Miscellaneous Folding Commands
Folding>Add Explicit Fold (shortcut: C+e a) surrounds the selection with “{{{” and “}}}”. If the
current buffer's edit mode defines comment strings (see the section called “Commenting Out Code”)
the explicit fold markers will automatically be commented out as well.
Folding>Select Fold (shortcut: C+e s) selects all lines within the fold containing the caret.
Control-clicking a fold expansion triangle in the gutter has the same effect.
Folding>Expand Folds With Level (shortcut: C+e ENTER key) reads the next character entered
at the keyboard, and expands folds in the buffer with a fold level less than that specified, while
collapsing all others.
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Editing Source Code
Sometimes it is desirable to have files open with folds initially collapsed. This can be configured as
follows:
• On a global or mode-specific basis in the Editing pane of the Utilities> Options dialog box. See
the section called “The Editing Pane”.
• In the current buffer for future editing sessions by placing the following in the first or last 10 lines
of a buffer, where level is the desired fold level:
:collapseFolds=level:
Narrowing
The narrowing feature temporarily “narrows” the display of a buffer to a specified region. Text
outside the region is not shown, but is still present in the buffer.
Holding down Alt while clicking a fold expansion triangle in the gutter will hide all lines the buffer
except those contained in the clicked fold.
Folding>Narrow Buffer to Fold (shortcut: C+e n n) hides all lines the buffer except those in the
fold containing the caret.
Folding>Narrow Buffer to Selection (shortcut: C+e n s) hides all lines the buffer except those
in the selection.
Folding>Expand All Folds (shortcut: C+e x) shows lines that were hidden as a result of
narrowing.
40
Chapter 7. Customizing jEdit
The Buffer Options Dialog Box
Utilities>Buffer Options displays a dialog box for changing editor settings on a per-buffer basis.
Changes made in this dialog box are not retained after the buffer is closed.
The following settings can be changed here:
• The line separator (see the section called “Line Separators”)
• The character encoding (see the section called “Character Encodings”)
• If the file should be GZipped on disk (see the section called “Opening Files”)
• Whether to show a dialog or auto-reload when this buffer's file is changed on disk.
• The edit mode (see the section called “Edit Modes”)
• The fold mode (see the section called “Folding”)
• The automatic indentation scheme (see the section called “Automatic Indent”)
• The wrap mode and margin (see the section called “Wrapping Long Lines”)
• The tab width (see the section called “Tabbing and Indentation”)
• The indent width
• If soft tabs should be used (see the section called “Tabbing and Indentation”)
Buffer-Local Properties
Buffer-local properties provide an alternate way to change editor settings on a per-buffer basis.
While changes made in the Buffer Options dialog box are lost after the buffer is closed, bufferlocal properties take effect each time the file is opened, because they are embedded in the file itself.
When jEdit loads a file, it checks the first and last 10 lines for colon-enclosed name/value pairs. For
example, placing the following in a buffer changes the indent width to 4 characters, enables soft
tabs, and activates the Perl edit mode:
:indentSize=4:noTabs=true:mode=perl:
Adding buffer-local properties to a buffer takes effect after the the buffer is saved and loaded again.
The following table describes each buffer-local property in detail.
Property name
Description
collapseFolds
Folds with a level of this or higher will be collapsed when the buffer is
opened. If set to zero, all folds will be expanded initially. See the section
called “Folding”.
deepIndent
When set to “true”, multiple-line expressions delimited by parentheses are
aligned like so:
retVal.x = (int)(horizontalOffset
+ Chunk.offsetToX(info.chunks,
offset));
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Customizing jEdit
Property name
Description
With this setting disabled, the text would look like so:
retVal.x = (int)(horizontalOffset
+ Chunk.offsetToX(info.chunks,
offset));
folding
The fold mode; one of “none”, “indent”, “explicit”, or the name of a
plugin folding mode. See the section called “Folding”.
indentSize
The width, in characters, of one indent. Must be an integer greater than 0.
See the section called “Tabbing and Indentation”.
maxLineLen
The maximum line length and wrap column position. Inserting text
beyond this column will automatically insert a line break at the
appropriate position. See the section called “Inserting and Deleting Text”.
mode
The default edit mode for the buffer. See the section called “Edit Modes”.
noTabs
If set to “true”, soft tabs (multiple space characters) will be used instead
of “real” tabs. See the section called “Tabbing and Indentation”.
noWordSep
A list of non-alphanumeric characters that are not to be treated as word
separators. Global default is “_”.
tabSize
The tab width. Must be an integer greater than 0. See the section called
“Tabbing and Indentation”.
wordBreakChars
Characters, in addition to spaces and tabs, at which lines may be split
when the word wrap mode is set to “hard”. See the section called
“Wrapping Long Lines”.
wrap
The word wrap mode; one of “none”, “soft”, or “hard”. See the section
called “Wrapping Long Lines”.
autoIndent
The automatic indentation scheme; one of “none”, “full”, or “simple”. See
the section called “Automatic Indent”.
You may see :encoding=XXX: in a file as it is a buffer-local property and specifying the
character encoding for the file. But it is not really a buffer-local property, and behaves differently.
It is detected by buffer-local-property detector only if the detector is selected in encoding
options. Thus, it works only at loading, and it must appear near the top of the file. See the section
called “Character Encodings”.
The Global Options Dialog Box
Utilities>Options displays the options dialog. It has 2 tabs, the first is Global Options. This tab
contains several options panes, each containing a set of related options. Use the list on the left
splitter to switch between panes. Only panes created by jEdit are described here; Plugin Options
panes are created and documented by the plugins themselves.
The General Pane
The General pane contains various settings, such as the number of recent files to remember, when
to check for changed files, if the recent file list should be sorted, what current locale to use, if caret
positions or markers in buffers should be saved, if previously open files or split configurations
should be restored on startup, and so on.
If Open Buffers Are Changed On Disk... . If Do Nothing is selected, then modifications from
jEdit will silently clobber changes made from other processes during saves. Don't use this option
unless you know what you are doing! Also, changing this option here only affects newly opened
buffers, not the ones that are currently open. You can also change this setting for individual buffers
from Buffer Options. the section called “The Buffer Options Dialog Box”
42
Customizing jEdit
Check for changed buffers upon... . This option allows you choose additional times that jEdit
checks for changed files on disk. For slow or remote file systems, removing unnecessary file status
checks might improve performance. Regardless of the choice here, files are still checked before
save, unless Do Nothing is also selected for the previous option.
The Abbreviations Pane
The Abbreviations option pane can be used to enable or disable automatic abbreviation expansion,
and to edit currently defined abbreviations.
The combo box labelled “Abbrev set” selects the abbreviation set to edit. The first entry, “global”,
contains abbreviations available in all edit modes. The subsequent entries correspond to each mode's
local set of abbreviations.
To change an abbreviation or its expansion, either double-click the appropriate table entry, or
click a table entry and then click the Edit button. This will display a dialog box for modifying the
abbreviation.
The Add button displays a dialog box where you can define a new abbreviation. The Remove
button removes the currently selected abbreviation from the list.
See the section called “Positional Parameters” for information about positional parameters in
abbreviations.
The Appearance Pane
The Appearance pane can be used to change the appearance of user interface controls such as
buttons, labels and menus. It can also be used to change the icon set, or look and feel, enable/disable
the splash screen or system tray, and other appearance tweaks. You can also set the number of items
retained in history text fields, see Appendix C, History Text Fields.
The Context Menu Pane
The Context Menu option pane edits the text area's right-click context menu. See the section called
“Multiple Views”.
The Docking Pane
The Docking option pane shows a list of available dockables, and allows you to specify docking
locations for each of them. Another way to specify docking locations is to use the popup menus
associated with each dockable window.
It is possible to configure jEdit to automatically load and/or save Docking Layouts (similar to
eclipse perspectives) based on the edit mode of your current buffer through the checkboxes in this
pane. See the section called “Window Docking Layouts”.
jEdit also supports alternate docking frameworks. If the appropriate plugins are installed (Currently
only MyDoggy is available), you can change docking frameworks from here.
The Editing Pane
The Editing option pane contains settings such as the tab size, syntax highlighting and soft tabs on a
global or mode-specific basis.
Changing options from this optionpane does not change XML mode definition files on disk; it
merely writes values to the user properties file which override those set in mode files. To find out
43
Customizing jEdit
how to edit mode files directly, see Part II, “Writing Edit Modes”. Some of these options can be
further overridden on an individual file basis through the use of buffer-local properties.
The File name glob and First line glob text fields let you specify a glob pattern that
paths and first lines of buffers will be matched against to determine the edit mode. See Appendix D,
Glob Patterns for information about glob patterns.
The Extra Word Characters allows you to set the noLineSep buffer property on a modewide basis, allowing you to define what is considered part of a word when double-clicking on it in
the text area.
The Deep Indent option instructs jEdit to indent subsequent lines so that they line up with the
open bracket on the previous line.
The Encodings Pane
This option pane offers users of jEdit many flexible options for defining how Encodings are handled
in jEdit. See the section called “Character Encodings” for the basics.
The default line separator character (see the section called “Line Separators”) can be set from here.
Use autodetection when possible is an option you can switch on or off.
The List of Encoding Autodetector Names can be used to control what encoding
detections are used on each file when it is loaded. The order they appear in this list determines the
order of detectors that are tried. There are some detectors which are available with jEdit core:
• BOM: detects Byte Order Mark.
• XML-PI: detects encoding declaration in XML Processing Instruction.
• html: detects charset description in HTML META element.
• python: detects various encoding declaration accepted in Python. This accepts encoding
declarations for GNU Emacs or Bram Moolenaar's VIM.
• buffer-local-property: detects same syntax described at the section called “Buffer-Local
Properties” for property name "encoding". Note that unlike other buffer-local properties, this one
will not work unless it is at the top of the file, and this appears in the list of encoding detectors.
Others can be defined in plugins as services and added to this space-separated list. See
EncodingDetector for details on how to offer additional encoding autodetector.
The List of Fallback Encodings is used when a file fails to open in the default encoding,
and the Encoding Autodetectors also fail. The list order here determines the order of encodings
that are tried. Each is separated by a space. This is especially handy when doing directory searches
through files of different encodings. We suggest using UTF-8 as either your default or one of the
fallback encodings.
While jEdit allows you to edit files in a variety of different encodings, the average user switches
between only 2 or 3. In other parts of jEdit, where the list of encodings is displayed in a combobox
(such as the buffer options) or a menu (such as File - Reload with Encoding submenu) it may be
desirable to display only a subset of available encodings, those that are in common local use. The
Encodings checkbox list allows the user to select the subset of supported encodings to display in
other GUI components that list all of the encodings.
The Gutter Pane
The Gutter option pane contains settings to customize the appearance of the gutter. You can
customize values such as "minimal number of digits to reserve for line numbers", and "fold style".
See the section called “Interface Overview”.
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Customizing jEdit
The Mouse Pane
The Mouse option pane contains settings for toggling drag and drop of text, as well as gutter mouse
click behavior.
The only option that may not be self-explanatory is the Double-Click drag joins nonalphanumeric characters. This option means that double-click will select a region that includes
the non-alphabetical characters, as defined for the current mode. The actual set of characters can be
defined for an indiviual file via buffer-local properties (noWordSep) or on a mode-wide basis from
the Editing option pane (Extra Word Characters).
The Plugin Manager Pane
The Plugin Manager pane contains a chooser for the desired download mirror, as well as various
settings such as the directory where plugins are to be installed. In addition, you can set the time
in minutes that the pluginlist can be cached from jedit.org, helping to reduce the server load. See
Chapter 9, Installing and Using Plugins.
If the option Disable Obsolete Plugins is checked, then plugins that were released on Plugin
Manager will be checked against the plugins you have installed, for those with a maximum jEdit
version that is lower than the one you are running. Plugins are marked with a maximum jEdit
version when they are found to be broken or somehow incompatible with a given jEdit release. Until
an update is made available for such a plugin on Plugin Manager, these plugins are automatically
unloaded and marked unsupported. This should improve the stability of jEdit.
If you re-enable a plugin that was disabled this way, it will remain loaded until the next time the
plugin list is checked - whenever the user selects the Update or Install tab from Plugin Manager. If
you un-check this option, then plugins will not be automatically disabled in this way.
The Printing Pane
The Printing option pane contains settings to control the appearance of printed output.
Workarounds that might be needed for your Java version to print correctly can also be enabled here.
See the section called “Printing”.
The Proxy Servers Pane
The Proxy Servers option pane lets you specify HTTP and SOCKS proxy servers to use when jEdit
makes network connections, for example when downloading plugins.
The Saving and Backup Pane
The Saving and Backup option pane contains settings for the autosave and backup features. See the
section called “Autosave and Crash Recovery” and the section called “Backups”.
The Shortcuts Pane
The Shortcuts option pane associates keyboard shortcuts with commands. Each command can have
up to two shortcuts associated with it, and each shortcut can be a single or multiple key sequence.
jEdit 5 introduces a new feature known as "keymaps". Each keymap is a named set of keyboard
shortcut mappings. Default keymaps are found in jEdit's keymaps folder, and user customized
keymaps are are stored in the user settings' keymaps folder.
The top combobox allows you to Choose a Keymap, or a set of shortcuts. The "imported" keymap
is automatically created and selected when jEdit needs to initially create a "keymaps" user settings
45
Customizing jEdit
folder. At this point, jEdit imports the existing shortcuts and places them into "imported". This
makes it easy to bring in shortcuts from properties files that were customized with jEdit 4.5 or
earlier.
If a keymap of the same name exists in the defaults and the user settings directory, the user version
is the one that is used in favor of the default. To take an existing keymap and customize it, select it,
click duplicate and you will be asked for the name of the new keymap. A copy of that keymap will
be saved in the user settings keymaps directory. At this point, this keymap will be selected and
will determine where new shortcut properties are stored. To remove all customizations and restore a
default keymap, click reset.
The combo box below the keymap selector selects the command set to edit. Command sets exist for
the set of all built-in commands, the commands of each plugin, and the set of macros.
To change a shortcut, click the appropriate table entry and press the keys you want associated with
that command in the resulting dialog box. The dialog box will warn you if the shortcut is already
assigned. The properties will be saved in the currently selected keymap.
The Status Bar Pane
The Status Bar, its API, and its corresponding option pane contains settings to customize which
widgets are in the status bar, their order, and what separators exist between them. Also, you can
disable it completely, for regular and/or plain views. See the section called “The Status Bar”.
From the Options tab, you can customize information about the caret display in the lower left
corner.
Selecting the Widgets tab of this option pane shows you what widgets on the right, and their
order. You can add or remove widgets and separators/labels here.
The Syntax Highlighting Pane
The Syntax Highlighting pane can be used to customize the fonts and colors for syntax
highlighting. See the section called “Syntax Highlighting”.
The Text Area Pane
The Text Area pane contains settings to customize the appearance of the text area.
You can configure the Text Font, antialias settings, colors, cursor style, highlight matching, and
word-completion settings from here.
Fractional Font Metrics is an old option that helps with certain versions of Java, but usually not in
combination with subpixel antialiasing.
Additional Fonts with font substitution if checked, shows a list of Preferred fonts, as well as the
following option. Fonts added to this list will determine the order jEdit searches for glyphs that may
be missing from your chosen Text Font.
If the Font Substitution: Search all system fonts option is checked, all of the installed fonts are
searched for glyphs, after the preferred list is searched. If this option is checked, no fonts need to be
added to preferred fonts list. You probably don't want to un-check either of these options unless you
want to test a system with limited fonts.
The Tool Bar Pane
The Tool Bar option pane lets you edit the tool bar, or disable it completely. See the section called
“Multiple Views”.
46
Customizing jEdit
The View Pane
The View option pane lets you change various settings related to the editor main window
appearance, including the arrangement of dockable windows, whether the search bar and buffer
switcher are visible, and whether menu, toolbar, and statusbar are visible in full-screen mode. See
the section called “Multiple Views”.
You can choose the default bufferset scope here, as well as whether/how you want buffersets to be
sorted in buffer switchers. See the section called “Buffer Sets” for more details.
If Abbreviate paths with environment variables when possible is checked, you will notice that
jEdit displays abbreviated versions of file paths when it can, using $VARIABLE/name.ext
or %VARIABLE%\name.ext syntax, depending on your platform. Abbreviating is used in the
File System Browser, as well as in the window title, and in plugins, to save horizontal space.
Reverse-expansions also work as you would expect them to, with both syntaxes recognized on both
platforms.
The File System Browser Panes
The File System Browser group contains two option panes, General and Colors. The former
contains various file system browser settings. The latter configures glob patterns used for coloring
the file list. See the section called “The File System Browser (FSB)” for more information.
The jEdit Settings Directory
jEdit stores settings, keymaps, macros, and plugins as files inside the settings directory. In most
cases, editing these files by hand is not necessary, since graphical tools and editor commands can do
the job. However, being familiar with the structure of the settings directory still comes in handy in
certain situations, for example when you want to copy jEdit settings between computers.
The location of the settings directory is system-specific 1. It is printed to the activity log
(Utilities>Troubleshooting>Activity Log). For example:
[message] jEdit: Settings directory is /home/slava/.jedit
Another way to find the location of your settings directory is to use the "Utilities" menu, then the
"Settings Directory" menu item. The first item in the pullout menu is the location of your settings
directory.
Specifying the -settings switch on the command line instructs jEdit to store settings in a
directory other than the default. For example, the following command will instruct jEdit to store all
settings in the jedit subdirectory of the C: drive:
C:\jedit> jedit -settings=C:\jedit
The -nosettings switch will force jEdit to not look for or create a settings directory; default
settings will be used instead.
jEdit creates the following files and directories inside the settings directory; plugins may add more:
• abbrevs - a plain text file which stores all defined abbreviations. See the section called
“Abbreviations”.
• activity.log - a plain text file which contains the full activity log. See Appendix B, The
Activity Log.
1
On Linux, it is ~/.jedit. On Windows, you will find it in %APPDATA%\jEdit. On the Mac, it is ~/Library/jEdit.
47
Customizing jEdit
• history - a plain text file which stores history lists, used by history text fields and the
Edit>Paste Previous command. See the section called “Transferring Text” and Appendix C,
History Text Fields.
• jars - this directory contains plugins. See Chapter 9, Installing and Using Plugins.
• jars-cache - this directory contains plugin cache files which decrease the time to start jEdit.
They are automatically updated when plugins are installed or updated.
• keymaps - this directory contains collections of named keyboard shortcuts which can be defined
from the Shortcuts Option Pane (see the section called “The Shortcuts Pane”).
• killring.xml - stores recently deleted text. See the section called “Transferring Text”.
• macros - this directory contains macros. See Chapter 8, Using Macros.
• modes - this directory contains custom edit modes. See Part II, “Writing Edit Modes”.
• perspective.xml - an XML file that stores the list of open buffers and views used to
maintain editor state between sessions.
• PluginManager.download - this directory is usually empty. It only contains files while
the plugin manager is downloading a plugin. For information about the plugin manager, see
Chapter 9, Installing and Using Plugins.
• pluginMgr-Cached.xml.gz - this contains a cached copy of the last XML plugin list
downloaded from plugin central. If you delete this file, a new one will be created next time you
try to install a plugin via Plugin Manager.
• printspec - a binary file that stores printing settings.
• properties - a plain text file that stores the majority of jEdit's and its plugins settings. For
more information see the section called “The jEdit properties file”.
• recent.xml - an XML file which stores the list of recently opened files. jEdit remembers the
caret position and character encoding of each recent file, and automatically restores those values
when one of the files is opened.
• registers.xml - an XML file that stores register contents. See the section called “General
Register Commands” for more information about registers.
• server - a plain text file that only exists while jEdit is running. The edit server's port number
and authorization key is stored here. See Chapter 2, Starting jEdit.
• settings-backup - this directory contains numbered backups of all automatically-written
settings files.
• startup - This directory contains startup scripts in beanshell or other plugin-supported
scripting languages. They are run at the time jEdit starts, after the startup scripts in the jEdit
install directory have been run. See the section called “Startup Scripts”
The jEdit properties file
The jEdit properties file uses the Java properties syntax to store key/value pairs. All of the
values are stored as strings, but are interpreted as other types (such as integer or boolean) by plugins
at runtime.
Do not edit this file while jEdit is running. If you do, it is possible that your changes (either your
edits, or jEdit settings changes) may get lost.
48
Customizing jEdit
Site Properties
You may also put properties files in the properties directory under the jEdit home directory
(NOT the jedit settings directory). You can locate the jEdit home directory by going to the Utilities
menu directory, then the jEdit Home Directory menu item, and the first item in the pullout menu
will be the location of the jEdit home directory. This is intended for site-wide settings. This lets you
keep custom user properties separate from the jEdit site-wide properties, so they are easier to find,
edit, and move between machines. Note that your custom properties files must have ".props" as the
file name extension.
Prior to jEdit 5.0, this was also where site-wide keyboard shortcuts were placed, but now you can
define custom sets of shortcuts as keymap files. These files can be cloned and edited from the
Shortcuts Option Pane, or edited by hand. To place them in a system-wide location, copy them into
the keymaps folder under the jedit home directory.
Site properties files are read in alphabetically by file name. This means that if you have a property
with the same name in more than one file, the value for that property will be the value found in the
last file that was read.
You can edit these files inside jEdit - changes made to these files will not be re-read until the next
time jEdit is started.
49
Chapter 8. Using Macros
Macros in jEdit are short scripts written in a scripting language called BeanShell. They provide an
easy way to automate repetitive keyboard and menu procedures, as well as access to the objects
and methods created by jEdit. Macros also provide a powerful facility for customizing jEdit and
automating complex text processing and programming tasks. This section describes how to record
and run macros. A detailed guide on writing macros appears later; see Part III, “Writing Macros”.
Other scripting languages
A number of jEdit plugins provide support for writing scripts in alternative programming
languages, like Python and Prolog. Consult the documentation for the appropriate plugins for
more information.
Recording Macros
The simplest use of macros is to record a series of key strokes and menu commands as a BeanShell
script, and play them back later. While this doesn't let you take advantage of the full power of
BeanShell, it is still a great time saver and can even be used to “prototype” more complicated
macros.
Macros>Record Macro (shortcut: C+m C+r) prompts for a macro name and begins recording.
While recording is in progress, the string “Macro recording” is displayed in the status bar. jEdit
records the following:
• Key strokes
• Menu item commands
• Tool bar clicks
• All search and replace operations, except incremental search
Mouse clicks in the text area are not recorded; use text selection commands or arrow keys instead.
Macros>Stop Recording (shortcut: C+m C+s) stops recording. It also switches to the buffer
containing the recorded macro, giving you a chance to check over the recorded commands and make
any necessary changes. When you are happy with the macro, save the buffer and it will appear in the
Macros menu. To discard the macro, close the buffer without saving it.
The file name extension .bsh is automatically appended to the macro name, and all spaces are
converted to underscore characters, in order to make the macro name a valid file name. These two
operations are reversed when macros are displayed in the Macros menu; see the section called
“How jEdit Organizes Macros” for details.
If a complicated operation only needs to be repeated a few times, using the temporary macro feature
is quicker than saving a new macro file.
Macros>Record Temporary Macro (shortcut: C+m C+m) begins recording to a buffer named
Temporary_Macro.bsh. Once recording of a temporary macro is complete, jEdit does not
display the buffer containing the recorded commands, but the name Temporary_Macro.bsh
will be visible on any list of open buffers. By switching to that buffer, you can view the commands,
edit them, and save them if you wish to a permanent macro file. Whether or not you look at or save
the temporary macro contents, it is immediately available for playback.
Macros>Run Temporary Macro (shortcut: C+m C+p) plays the macro recorded to the
Temporary_Macro.bsh buffer.
50
Using Macros
Only one temporary macro is available at a time. If you begin recording a second temporary macro,
the first is erased and cannot be recovered unless you have saved the contents to a file with a name
other than Temporary_Macro.bsh. If you do not save the temporary macro, you must keep the
buffer containing the macro script open during your jEdit session. To have the macro available for
your next jEdit session, save the buffer Temporary_Macro.bsh as an ordinary macro with a
descriptive name of your choice. The new name will then be displayed in the Macros menu.
Running Macros
Macros supplied with jEdit, as well as macros that you record or write, are displayed under
the Macros menu in a hierarchical structure. The jEdit installation includes about 30 macros
divided into several major categories. Each category corresponds to a nested submenu under the
Macros menu. An index of these macros containing short descriptions and usage notes is found in
Appendix F, Macros Included With jEdit.
To run a macro, choose the Macros menu, navigate through the hierarchy of submenus, and select
the name of the macro to execute. You can also assign execution of a particular macro to a keyboard
shortcut, toolbar button or context menu using the Macro Shortcuts, Tool Bar or Context Menu
panes of the Utilities>Options dialog; see the section called “The Global Options Dialog Box”.
How jEdit Organizes Macros
Every macro, whether or not you originally recorded it, is stored on disk and can be edited as a
text file. The file name of a macro must have a .bsh extension in order for jEdit to be aware of
it. By default, jEdit associates a .bsh file with the BeanShell edit mode for purposes of syntax
highlighting, indentation and other formatting. However, BeanShell syntax does not impose any
indentation or line break requirements.
The Macros menu lists all macros stored in two places: the macros subdirectory of the jEdit home
directory, and the macros subdirectory of the user-specific settings directory (see the section called
“The jEdit Settings Directory” for information about the settings directory). Any macros you record
will be stored in the user-specific directory.
Macros stored elsewhere can be run using the Macros>Run Other Macro command, which
displays a file chooser dialog box, and runs the specified file.
The listing of individual macros in the Macros menu can be organized in a hierarchy using
subdirectories in the general or user-specific macro directories; each subdirectory appears as a
submenu. You will find such a hierarchy in the default macro set included with jEdit.
When jEdit first loads, it scans the designated macro directories and assembles a listing of
individual macros in the Macros menu. When scanning the names, jEdit will delete underscore
characters and the .bsh extension for menu labels, so that List_Useful_Information.bsh,
for example, will be displayed in the Macros menu as List Useful Information.
You can browse the user and system macro directories by opening the macros directory from the
Utilities>jEdit Home Directory and Utilities>Settings Directory menus.
Macros can be opened and edited much like ordinary files from the file system browser. Editing
macros from within jEdit will automatically update the macros menu; however, if you modify
macros from another program or add macro files to the macro directories, you should run the
Macros>Rescan Macros command to update the macro list.
51
Chapter 9. Installing and Using
Plugins
A plugin is an application which is loaded and runs as part of another, host application. Plugins
respond to user commands and perform tasks that supplement the host application's features.
This chapter covers installing, updating and removing plugins. Documentation for the plugins
themselves can be found in Help>jEdit Help, and information about writing plugins can be found
in Part IV, “Writing Plugins”.
The Plugin Manager
Plugins>Plugin Manager displays the plugin manager window. It consists of three tabs: Manage,
Update and Install. The Manage tab lists all installed plugins; clicking on a plugin in the list will
display information about it.
To remove plugins, select them (multiple plugins can be selected by holding down Control) and
click Remove. This will display a confirmation dialog box first.
To view plugin documentation, select a plugin and click Help. Note that plugin documentation can
also be accessed by invoking Help>jEdit Help.
After you have tuned jEdit to your liking and want to install the same set of plugins onto another
host, or another user's profile, you can export your currently installed plugin list as an xml file,
known as a PluginSet. The Save rollover button allows you to save the list of installed and loaded
plugins to an XML file. See the section called “Plugin Sets” for more information.
Plugins>Plugin Options displays a dialog box for changing plugin settings.
Installing and Updating Plugins
Plugins can be installed in two ways; manually, and from the plugin manager. In most cases, plugins
should be installed from the plugin manager. It is easier and more convenient.
To install plugins manually, go to http://plugins.jedit.org in a web browser and follow the directions
on that page.
To install plugins from the plugin manager, make sure you are connected to the Internet and click
the Install tab in the plugin manager window. The plugin manager will then download information
about available plugins from the jEdit web site, and present a list of plugins compatible with your
jEdit release.
Click on a plugin in the list to see some information about it. To select plugins for installation, click
the check box next to their names in the list.
The Total size field shows the total size of all plugins chosen for installation, along with any
plugins that will be automatically downloaded in order to fulfill dependencies.
If a previously saved PluginSet was selected, it will automatically be loaded whenever the Install tab
is created, and you will see the filename in the hovertip of the choose rolloverbutton, as well as all
of the plugins in that set already checked for you.
You can clear the active PluginSet with the clear button next to it, or choose a different PluginSet
xml file with the choose button. See the section called “Plugin Sets” for more information.
Once you have specified plugins to install, click Install to begin the download process.
52
Installing and Using Plugins
By default, the plugin manager does not download plugin source code, and installs the downloaded
plugins in the jars subdirectory of the user-specific settings directory. These settings can be
changed in Plugin Manager pane of the Utilities>Options dialog box; see the section called “The
Plugin Manager Pane”.
The Update tab of the plugin manager is very similar to the Install tab. It lists plugins for which
updated versions are available. It will also offer to delete any obsolete plugins.
Proxy Servers and Firewalls
If you are connected to the Internet through an HTTP proxy or SOCKS firewall, you will
need to specify the relevant details in the Proxy Servers pane of the Utilities>Options dialog
box; see the section called “The Proxy Servers Pane”.
Plugin Sets
A PluginSet is a collection of plugins, represented as an XML file. These XML files can be created
from the save button of the Manage tab of the Plugin Manager. Saving a PluginSet remembers all of
the currently loaded plugins.
When a PluginSet has been saved, it becomes the "default pluginset", which means that if you
unload/uninstall plugins from that set and go back to the Install tab, you should see them selected
for download again. To clear this setting, click on the clear button in the Install tab.
It is posisble to Choose/Open a PluginSet from the Manage or the Install tab. The behavior of
choosing a PluginSet depends on which tab you are on when you choose it. From the Manage tab,
it unloads plugins that are loaded but not in the list. From the Install tab, it selects plugins from that
list that are not loaded, marking them for download from Plugin Central.
When choosing a PluginSet, the path can be given as a remote URL. This helps teachers and
sysadmins direct the students/slaves to a standard set of plugins that are required for the course/job.
53
Appendix A. Keyboard Shortcuts
This appendix documents the "jEdit" keymap of keyboard shortcuts. Keymaps can be created and
customized to suit your taste in the Shortcuts pane of the Utilities>Options dialog box; see the
section called “The Shortcuts Pane”.
Files
For details, see the section called “Switching Buffers”, the section called “Multiple Views” and
Chapter 4, Working With Files.
C+n
New file.
C+o
Open file.
C+w
Close buffer.
C+e C+w
Close all buffers.
C+s
Save buffer.
C+e C+s
Save all buffers.
C+p
Print buffer.
C+PAGE_UP
Go to previous buffer.
C+PAGE_DOWN
Go to next buffer.
C+`
Go to recent buffer.
A+`
Show buffer switcher.
C+q
Exit jEdit.
Views
For details, see the section called “Multiple Views”.
C+e C+t
Turn gutter (line numbering) on and off.
C+0
Remove split containing current text area only.
C+1
Remove all splits.
C+2
Split view horizontally.
C+3
Split view vertically.
A+PAGE_UP
Send keyboard focus to previous text area.
A+PAGE_DOWN
Send keyboard focus to next text area.
C+e UP; LEFT; DOWN; RIGHT
Send keyboard focus to top; bottom; left; right docking area.
C+e C+`
Close currently focused docking area.
Action Bar
For details, see the section called “The Action Bar”.
C+ENTER
Display the action bar and give it keyboard focus.
C+SPACE
Repeat last editor action.
54
Keyboard Shortcuts
Moving the Caret
For details, see the section called “Moving The Caret”, the section called “Working With Words”,
the section called “Working With Lines”, the section called “Working With Paragraphs” and the
section called “Bracket Matching”.
Arrow
Move caret one character or line.
C+Arrow
Move caret one word or paragraph.
PAGE_UP; PAGE_DOWN
Move caret one screenful.
HOME
First non-whitespace character of line, beginning of line, first
visible line (repeated presses).
END
Last non-whitespace character of line, end of line, last visible
line (repeated presses).
C+HOME
Beginning of buffer.
C+END
End of buffer.
C+]
Go to matching bracket.
C+e [; ]
Go to previous; next bracket.
C+l
Go to line.
Selecting Text
For details, see the section called “Selecting Text”, the section called “Working With Words”, the
section called “Working With Lines”, the section called “Working With Paragraphs” and the section
called “Bracket Matching”.
S+Arrow
Extend selection by one character or line.
CS+Arrow
Extend selection by one word or paragraph.
S+PAGE_UP; S+PAGE_DOWN
Extend selection by one screenful.
S+HOME
Extend selection to first non-whitespace character of line,
beginning of line, first visible line (repeated presses).
S+END
Extend selection to last non-whitespace character of line, end
of line, last visible line (repeated presses).
CS+HOME
Extend selection to beginning of buffer.
CS+END
Extend selection to end of buffer.
C+[
Select code block.
C+e w; l; p
Select word; line; paragraph.
C+e C+l
Select line range.
C+a
Select all.
ESCAPE
Select none.
A+\
Switch between range and rectangular selection mode.
C+\
Switch between single and multiple selection mode.
C+e i
Invert selection.
Scrolling
For details, see the section called “Multiple Views”.
55
Keyboard Shortcuts
C+e C+j
Ensure current line is visible, and send focus to the text area.
C+e C+n
Center caret on screen.
C+'; C+/
Scroll up; down one line.
A+'; A+/
Scroll up; down one page.
Text Editing
For details, see the section called “Undo and Redo”, the section called “Inserting and Deleting
Text”, the section called “Working With Words”, the section called “Working With Lines” and the
section called “Working With Paragraphs”.
C+z
Undo.
C+e C+z
Redo.
BACK_SPACE; DELETE
Delete character before; after caret.
C+BACK_SPACE; C+DELETE
Delete word before; after caret.
C+d; C+e d
Delete line; paragraph.
CS+BACK_SPACE; CS+DELETE Delete from caret to beginning; end of line.
C+e r
Remove trailing whitespace from the current line (or all
selected lines).
C+j
Join lines.
C+b
Complete word.
C+e f
Format paragraph (or selection).
Clipboard and Registers
For details, see the section called “Transferring Text”.
C+x or S+DELETE
Cut selected text to clipboard.
C+c or C+INSERT
Copy selected text to clipboard.
C+e C+u
Append selected text to clipboard, removing it from the buffer.
C+e C+a
Append selected text to clipboard, leaving it in the buffer.
C+v or S+INSERT
Paste clipboard contents.
C+e C+p
Vertically paste clipboard contents.
C+r C+x key
Cut selected text to register key.
C+r C+c key
Copy selected text to register key.
C+r C+u key
Append selected text to register key, removing it from the
buffer.
C+r C+a key
Append selected text to register key, leaving it in the buffer.
C+r C+v key
Paste contents of register key.
C+r C+p key
Vertically paste contents of register key.
C+e C+v
Paste previous.
C+e C+y
Paste deleted.
Markers
For details, see the section called “Markers”.
56
Keyboard Shortcuts
C+e C+m
If current line doesn't contain a marker, one will be added.
Otherwise, the existing marker will be removed. Use the
Markers menu to return to markers added in this manner.
C+t key
Add marker with shortcut key.
C+y key
Go to marker with shortcut key.
C+u key
Select to marker with shortcut key.
C+k key
Go to marker with shortcut key, and move the marker to the
previous caret position.
C+e C+,; C+e C+.
Move caret to previous; next marker.
Search and Replace
For details, see the section called “Search and Replace”.
C+f
Open search and replace dialog box.
C+g
Find next.
C+h
Find previous.
C+e C+b
Search in open buffers.
C+e C+d
Search in directory.
C+e C+r
Replace in selection.
C+e C+g
Replace in selection and find next.
C+,
Incremental search bar.
A+,
HyperSearch bar.
C+.
Incremental search for word under the caret.
A+.
HyperSearch for word under the caret.
C+e C+i
Toggle ignore case.
C+e C+x
Toggle regular expressions.
Source Code Editing
For details, see the section called “Abbreviations”, the section called “Tabbing and Indentation” and
the section called “Commenting Out Code”.
C+;
Expand abbreviation.
A+LEFT; A+RIGHT
Shift current line (or all selected lines) left; right.
S+TAB; TAB
Shift selected lines left; right. Note that pressing TAB with no
selection active will insert a tab character at the caret position.
C+i
Indent current line (or all selected lines).
C+e C+c
Range comment selection.
C+e C+k
Line comment selection.
Folding and Narrowing
For details, see the section called “Folding” and the section called “Narrowing”.
A+BACK_SPACE
Collapse fold containing caret.
A+ENTER
Expand fold containing caret one level only.
57
Keyboard Shortcuts
AS+ENTER
Expand fold containing caret fully.
C+e x
Expand all folds.
C+e a
Add explicit fold.
C+e s
Select fold.
C+e ENTER key
Expand folds with level less than key, collapse all others.
C+e n n
Narrow to fold.
C+e n s
Narrow to selection.
A+UP; A+DOWN
Moves caret to previous; next fold.
C+e u
Moves caret to the parent fold of the one containing the caret.
Macros
For details, see Chapter 8, Using Macros.
C+m C+r
Record macro.
C+m C+m
Record temporary macro.
C+m C+s
Stop recording.
C+m C+p
Run temporary macro.
Alternative Shortcuts
A few frequently-used commands have alternative shortcuts intended to help you keep your hands
from moving all over the keyboard.
A+j; A+l
Move caret to previous, next character.
A+i; A+k
Move caret up, down one line.
A+q; A+a
Move caret up, down one screenful.
A+z
First non-whitespace character of line, beginning of line, first
visible line (repeated presses).
A+x
Last non-whitespace character of line, end of line, last visible
line (repeated presses).
58
Appendix B. The Activity Log
The activity log is very useful for troubleshooting problems, and helps when developing plugins.
Utilities>Troubleshooting>Activity Log displays the last 500 lines of the activity log. By default,
the activity log is shown in a floating window. This window can be docked using the commands in
its top-left corner popup menu; see the section called “Window Docking Layouts”.
The complete log can be found in the activity.log file inside the jEdit settings directory, the
path of which is shown inside the activity log window.
jEdit writes the following information to the activity log:
• Information about your Java implementation (version, operating system, architecture, etc).
• All error messages and runtime exceptions (most errors are shown in dialog boxes as well, but the
activity log usually contains more detailed and technical information).
• All sorts of debugging information that can be helpful when tracking down bugs.
• Information about loaded plugins.
While jEdit is running, the log file on disk may not always accurately reflect what has been logged,
due to buffering being done for performance reasons. To ensure the file on disk is up to date, invoke
the Utilities>Troubleshooting>Update Activity Log on Disk command. The log file is also
automatically updated on disk when jEdit exits.
The Settings button in the Activity Log window shows a dialog that lets you adjust the output
colors, filter the messages by type, and lets you set the maximum number of lines to display. Note
that larger numbers will decrease the overall performance of jEdit since these lines are kept in
memory.
In the Settings pane there is also a debugging option, Beep on output. It allows for catching
problems right after they show up. Each error message entry is accompanied by a system beep.
Lower priority entries may be alerted this way, if the log option is used, see the section called
“Command Line Usage”.
59
Appendix C. History Text Fields
The text fields in many jEdit components, such as the file system browser, incremental search
bar, and action bar, all remember the last 20 entered strings by default. The number of strings to
remember can be changed in the Appearance pane of the Utilities>Options dialog box; see the
section called “The Appearance Pane”.
Pressing UP recalls previous strings. Pressing DOWN after recalling previous strings recalls later
strings.
Pressing S+UP or S+DOWN will search backwards or forwards, respectively, for strings beginning
with the text already entered in the text field.
Clicking the triangle to the right of the text field, or clicking with the right-mouse button anywhere
else will display a pop-up menu of all previously entered strings; selecting one will input it into
the text field. Selecting the first item, "previously entered strings:" pops up a dialog that lets you
change previously entered strings. Holding down Shift while clicking will display a menu of all
previously entered strings that begin with the text already entered.
Search and Replace fields
In jEdit 4.3, the search/replace history fields are multi-line textareas, so they no longer
use the same single-line history textfield described above. The multiline history textarea
behaves a little differently: UP and DOWN arrows go up and down a line in the textarea,
instead of through the previously entered strings. PageUp and PageDown are used
instead to select history strings, and there is no arrow combo button, although right-click
will still show you the history as a context menu.
60
Appendix D. Glob Patterns
jEdit uses glob patterns similar to those in the various Unix shells to implement file name filters in
the file system browser. Glob patterns resemble regular expressions somewhat, but have a much
simpler syntax. The following character sequences have special meaning within a glob pattern:
• ? matches any one character
• * matches any number of characters
• {!glob} Matches anything that does not match glob
• {a,b,c} matches any one of a, b or c
• [abc] matches any character in the set a, b or c
• [^abc] matches any character not in the set a, b or c
• [a-z] matches any character in the range a to z, inclusive. A leading or trailing dash will be
interpreted literally
Since we use java.util.regex patterns to implement globs, this means that in addition to the
above, a number of “character class metacharacters” may be used. Keep in mind, their usefulness
is limited since the regex quantifier metacharacters (asterisk, questionmark, and curly brackets)
are redefined to mean something else in filename glob language, and the regex quantifiers are not
available in glob language.
• \w matches any alphanumeric character or underscore
• \s matches a space or horizontal tab
• \S matches a printable non-whitespace.
• \d matches a decimal digit
Here are some examples of glob patterns:
• * - all files.
• *.java - all files whose names end with “.java”.
• *.[ch] - all files whose names end with either “.c” or “.h”.
• *.{c,cpp,h,hpp,cxx,hxx} - all C or C++ files.
• [^#]* - all files whose names do not start with “#”.
Using regexes instead of globs
Sometimes it is desirable to use a regular expression instead of a glob for specifying file sets. This
is because regular expressions are more powerful than globs and can provide the user with more
specific filename matching criteria. To avoid the glob-to-regex transformation, prefix your pattern
with the string (re), which will tell jEdit to not translate the following pattern into a regex (since it
already is one). For example:
(re).*\.(h|c(c|pp)?)
Matches *.c, *.cpp, *.h, *.cc
If you need to match files that begin with the glob-translate-disable prefix (re), you can escape it
with a leading backslash and the metacharacters will be translated into globs as before.
61
Appendix E. Regular Expressions
jEdit uses regular expressions from java.util.regex.Pattern to implement inexact search and replace.
Click there to see a complete reference guide to all supported meta-characters.
A regular expression consists of a string where some characters are given special meaning with
regard to pattern matching.
Inside XML files
Inside XML files (such as jEdit mode files), it is important that you escape XML special
characters, such as &, <, >, etc. You can use the XML plugin's "characters to entities" to
perform this mapping.
Inside Java / beanshell / properties files
Java strings are always parsed by java before they are processed by the regular expression
engine, so you must make sure that backslashes are escaped by an extra backslash (\\)
Within a regular expression, the following characters have special meaning:
Positional Operators
• ^ matches at the beginning of a line
• $ matches at the end of a line
• \B matches at a non-word break
• \b matches at a word boundary
One-Character Operators
• . matches any single character
• \d matches any decimal digit
• \D matches any non-digit
• \n matches the newline character
• \s matches any whitespace character
• \xNN matches hexadecimal character code NN
• \S matches any non-whitespace character
• \t matches a horizontal tab character
• \w matches any word (alphanumeric) character
• \W matches any non-word (alphanumeric) character
• \\ matches the backslash (“\”) character
Character Class Operator
• [abc] matches any character in the set a, b or c
62
Regular Expressions
• [^abc] matches any character not in the set a, b or c
• [a-z] matches any character in the range a to z, inclusive. A leading or trailing dash will be
interpreted literally
Subexpressions and Backreferences
• (abc) matches whatever the expression abc would match, and saves it as a subexpression. Also
used for grouping
• (?:...) pure grouping operator, does not save contents
• (?#...) embedded comment, ignored by engine
• (?=...) positive lookahead; the regular expression will match if the text in the brackets
matches, but that text will not be considered part of the match
• (?!...) negative lookahead; the regular expression will match if the text in the brackets does
not match, and that text will not be considered part of the match
• \n where 0 < n < 10, matches the same thing the nth subexpression matched. Can only be used
in the search string
• $n where 0 < n < 10, substituted with the text matched by the nth subexpression. Can only be
used in the replacement string
Branching (Alternation) Operator
• a|b matches whatever the expression a would match, or whatever the expression b would match.
Repeating Operators
These symbols operate on the previous atomic expression.
• ? matches the preceding expression or the null string
• * matches the null string or any number of repetitions of the preceding expression
• + matches one or more repetitions of the preceding expression
• {m} matches exactly m repetitions of the one-character expression
• {m,n} matches between m and n repetitions of the preceding expression, inclusive
• {m,} matches m or more repetitions of the preceding expression
Stingy (Minimal) Matching
If a repeating operator (above) is immediately followed by a ?, the repeating operator will stop at
the smallest number of repetitions that can complete the rest of the match.
On regex search
There are some known issues with the java.util.regex library, as it stands in Java.
In particular, it is possible to create regular expressions that hang the JVM, or cause stack
overflow errors, which was not as easy to accomplish using the legacy gnu.regexp
library. If you find that gnu.regexp, used in jEdit 4.2 and earlier, is more suitable for
your search/replace needs, you can try the XSearch plugin, which still uses it and can
provide a replacement to the built-in search dialog.
63
Appendix F. Macros Included With
jEdit
jEdit comes with a large number of sample macros that perform a variety of tasks. The following
index provides short descriptions of each macro, in some cases accompanied by usage notes.
In addition to the macros included with jEdit, a very large collection of user-contributed macros
is available in the “Downloads” section of the community.jedit.org web site. There are detailed
descriptions for each macro as well as a search facility.
C/C++ macros
These macros are useful for C/C++ programming.
• Include_Guard.bsh
Inserts conditional preprocessor directives around a header file, to prevent it from being included
multiple times.
The name of the generated preprocessor macro is based on the buffer's name.
• Toggle_Header_Source
Toggles between the header and the implementation file. Works for .c, .cxx, and .cpp extensions.
Clipboard Macros
These macros copy or cut text to the clipboard.
• Copy_Lines_Containing.bsh
Copies all lines from the current buffer, containing a user-supplied string, to the clipboard.
• Cut_Lines_Containing.bsh
Cuts all lines from the current buffer, containing a user-supplied string, to the clipboard.
• Copy_Selection_or_Line.bsh
If no text is selected, the current line is copied to the clipboard, otherwise the selected text is
copied to the clipboard. Some editors have this has the default copy behavior. To achieve the
same effect in jEdit, bind this macro to C+c in the Shortcuts pane of the Utilities> Options
dialog box.
• Cut_Selection_or_Line.bsh
If no text is selected, the current line is cut to the clipboard, otherwise the selected text is cut to
the clipboard. Some editors have this has the default cut behavior. To achieve the same effect in
jEdit, bind this macro to C+x in the Shortcuts pane of the Utilities> Options dialog box.
• Copy_Visible_Lines.bsh
Copies the visible lines from the current buffer to the Clipboard. Lines that are not visible becuase
they are folded are not copied.
• Paste_Indent.bsh
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Macros Included With jEdit
Pastes the content of the clipboard and indents it.
Editing Macros
These macros automate various text editing tasks.
• Duplicate_Lines_Above.bsh
Duplicates current/selected line(s) upward.
• Duplicate_Lines_Below.bsh
Duplicates current/selected line(s) downward.
• Emacs_Ctrl-K.bsh
Cuts and appends text, from the cursor to the end of the line, into the copy buffer.
• Emacs_Next_Line.bsh
Moves the cursor to the next line, centering the current line in the middle of the text area if the
cursor is at the bottom of the text area.
• Emacs_Previous_Line.bsh
Moves the cursor to the previous line, centering the current line in the middle of the text area if
the cursor is at the top of the text area.
• Go_to_Column.bsh
Prompts the user for a column position on the current line, then moves the caret there.
• Greedy_Backspace.bsh
If buffer is using soft tabs, this macro will backspace to the previous tab stop, if all characters
between the caret and the tab stop are spaces. In all other cases a single character is removed.
• Greedy_Delete.bsh
If a buffer is using soft tabs, this macro will delete tabSize number of spaces, if all the characters
between the caret and the next tab stop are spaces. In all other cases a single character is deleted.
• Greedy_Left.bsh
If a buffer is using soft tabs, this macro will move the caret tabSize spaces to the left, if all the
characters between the caret and the previous tab stop are all spaces. In all other cases, the caret is
moved a single character to the left.
• Greedy_Right.bsh
If a buffer is using soft tabs, this macro will move the caret tabSize spaces to the right, if all the
characters between the caret and the next tab stop are all spaces. In all other cases, the caret is
moved a single character to the right.
• Keywords_to_Upper_Case.bsh
Converts all keywords in the current buffer to upper case.
• Mode_Switcher.bsh
Displays a modal dialog with the current buffer's mode in a text field, allowing one to change the
mode by typing in its name.
65
Macros Included With jEdit
ENTER selects the current mode; if the text is not a valid mode, the dialog still dismisses, but
a warning is logged to the activity log. ESACPE closes the dialog with no further action. TAB
attempts to auto-complete the mode name. Pressing TAB repeatedly cycles through the possible
completions. SHIFT-TAB cycles through the completions in reverse.
• Move_Line_Down.bsh
Moves the current line down one, with automatic indentation.
• Move_Line_Up.bsh
Moves the current line up one, with automatic indentation.
• Open_Line_Above.bsh
Adds a new blank line before the current/selected line(s).
• Open_Line_Below.bsh
Adds a new blank line after the current/selected line(s).
• Toggle_Fold.bsh
Toggles visibility of current fold.
This is especially useful for fold toggling via keyboard.
File Management Macros
These macros automate the opening and closing of files.
• Browse_Buffer_Directory.bsh
Opens a the current buffer's directory in the file system browser.
• Browse_Directory.bsh
Opens a directory supplied by the user in the file system browser.
• Buffer_Switcher.bsh
Displays a modal dialog listing all open buffers, allowing one to switch to and/or close buffers.
ENTER switches to a buffer and closes the dialog, DELETE closes a buffer, SPACE switches to a
buffer but does not close the dialog.
• Close_All_Except_Active.bsh
Closes all files except the current buffer.
Prompts the user to save any buffer containing unsaved changes.
• Copy_Path_to_Clipboad.bsh
Copies the current buffer's path to the clipboard.
• Copy_Name_to_Clipboad.bsh
Copies the current buffer's filename to the clipboard.
• Duplicate_Buffer.bsh
Duplicates the current buffer into a new one.
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Macros Included With jEdit
• Delete_Current.bsh
Deletes the current buffer's file on disk, but doesn't close the buffer.
• Glob_Close.bsh
Closes all open buffers matching a given glob pattern.
• Insert_Selection.bsh
Assumes the current selection is file path and tries replaces the selection with the contents of the
file. Does nothing if no text is selected or the selection spans multiple lines.
• Next_Dirty_Buffer.bsh
Switches to the next dirty buffer, if there is one.
• Open_Path.bsh
Opens the file supplied by the user in an input dialog.
• Open_Selection.bsh
Opens the file named by the current buffer's selected text. Current VFS browser directory is also
tried as a parent of the filename, but only as a local path.
• Open_Selection_In_Desktop.bsh
Opens the file named by the current buffer's selected text using Desktop. That is opens the
file using operating system's default application. If a link is selected, it is browsed instead, using
default web browser. If no selection is active, the path under caret is used.
• Send_Buffer_To_Next_Split.bsh
If bufferset scope is set to EditPane, the current buffer is added to the next Editpane's bufferset.
• Toggle_ReadOnly.bsh
Toggles a local file's read-only flag. Uses platform-specific commands, so it only works on
Windows, Unix and MacOS X.
User Interface Macros
Description.
• Decrease_Font_Size.bsh
Decreases the font size in the gutter and text area by 1 point.
• Increase_Font_Size.bsh
Increases the font size in the gutter and text area by 1 point.
• Open_Context_Menu.bsh
Opens the text area context menu just below and to the right of the caret.
• Reset_TextArea.bsh
Performs a split and an unsplit of the current TextArea. Useful for those occasions when your
textarea is corrupt (painting the incorrect characters on the screen).
• Splitpane_Grow.bsh
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Macros Included With jEdit
When inside a split EditPane, this macro moves the splitter away from the cursor, effectively
increasing the size of the currently active split pane.
• Toggle_Bottom_Docking_Area.bsh
Expands or collapses the bottom docking area, depending on it's current state.
• Toggle_Left_Docking_Area.bsh
Expands or collapses the left docking area, depending on it's current state.
• Toggle_Right_Docking_Area.bsh
Expands or collapses the right docking area, depending on it's current state.
• Toggle_Top_Docking_Area.bsh
Expands or collapses the top docking area, depending on it's current state.
Java Code Macros
These macros handle text formatting and generation tasks that are particularly useful in writing Java
code.
• Create_Constructor.bsh
Inserts constructor for the class at the current caret position.
• Get_Class_Name.bsh
Inserts a Java class name based upon the buffer's file name.
• Get_Package_Name.bsh
Inserts a plausible Java package name for the current buffer.
The macro compares the buffer's path name with the elements of the classpath being used by
the jEdit session. An error message will be displayed if no suitable package name is found. This
macro will not work if jEdit is being run as a JAR file without specifying a classpath; in that case
the classpath seen by the macro consists solely of the JAR file.
• Java_File_Save.bsh
Acts as a wrapper script to the Save As action. If the buffer is a new file, it scans the first 250 lines for a Java
class or interface declaration. On finding one, it extracts the appropriate filename to be used in the Save As
dialog.
• Make_Get_and_Set_Methods.bsh
Creates getXXX() or setXXX() methods that can be pasted into the buffer text.
This macro presents a dialog that will “grab” the names of instance variables from the caret line
of the current buffer and paste a corresponding getXXX() or setXXX() method to one of two
text areas in the dialog. The text can be edited in the dialog and then pasted into the current buffer
using the Insert... buttons. If the caret is set to a line containing something other than an instance
variable, the text grabbing routine is likely to generate nonsense.
As explained in the notes accompanying the source code, the macro uses a global variable which
can be set to configure the macro to work with either Java or C++ code. When set for use with C
++ code, the macro will also write (in commented text) definitions of getXXX() or setXXX()
suitable for inclusion in a header file.
68
Macros Included With jEdit
• Preview_Javadoc_of_Buffer.bsh
Create and display API documentation for the current buffer.
The macro includes various configuration variables you can change; see the comment at the
beginning of the macro source for details.
Miscellaneous Macros
While these macros do not fit easily into the other categories, they all provide interesting and useful
functions.
• Buffer_to_HyperSearch_Results.bsh
Reads HyperSearch results from a buffer that was previously created by the
HyperSearch_Results_to_Buffer macro and possibly filtered manually, and imports them into the
HyperSearch Results dockable.
• Debug_BufferSets.bsh
Display int and hex values for the character at the caret, in the status bar.
• Display_Abbreviations.bsh
Displays the abbreviations registered for each of jEdit's editing modes.
The macro provides a read-only view of the abbreviations contained in the “Abbreviations”
option pane. Pressing a letter key will scroll the table to the first entry beginning with that letter.
A further option is provided to write a selected mode's abbreviations or all abbreviations in a text
buffer for printing as a reference. Notes in the source code listing point out some display options
that are configured by modifying global variables.
• Display_Actions.bsh
Displays a list of all the actions known to jEdit categorised by their action set.
This macro can be a useful reference if you want to use the jEdit 4.2 action bar.
• Display_Character_Code.bsh
Display int and hex values for the character at the caret, in the status bar.
• Display_Shortcuts.bsh
Displays a sorted list of the keyboard shortcuts currently in effect.
The macro provides a combined read-only view of command, macro and plugin shortcuts.
Pressing a letter key will scroll the table to the first entry beginning with that letter. A further
option is provided to write the shortcut assignments in a text buffer for printing as a reference.
Notes in the source code listing point out some display options that are configured by modifying
global variables.
• Evaluate_Buffer_in_BeanShell.bsh
Evaluates contents of current buffer as a BeanShell script, and opens a new buffer to receive any
text output.
This is a quick way to test a macro script even before its text is saved to a file. Opening a
new buffer for output is a precaution to prevent the macro from inadvertently erasing or
overwriting itself. BeanShell scripts that operate on the contents of the current buffer will not
work meaningfully when tested using this macro.
69
Macros Included With jEdit
• Hex_Convert.bsh
Converts byte characters to their hex equivalent, and vice versa.
• HyperSearch_Results_to_Buffer.bsh
Writes HyperSeach results to a new buffer.
This buffer can be re-imported to the HyperSearch Results dockable by the
Buffer_to_HyperSearch_Results macro.
• Make_Bug_Report.bsh
Creates a new buffer with installation and error information extracted from the activity log.
The macro extracts initial messages written to the activity log describing the user's operating
system, JDK, jEdit version and installed plugins. It then appends the last set of error messages
written to the activity log. The new text buffer can be saved and attached to an email message or a
bug report made on SourceForge.
• Run_Script.bsh
Runs script using interpreter based upon buffer's editing mode (by default, determined using file
extension). You must have the appropriate interpreter (such as Perl, Python, or Windows Script
Host) installed on your system.
• Show_Threads.bsh
Displays in a tree format all running Java threads of the current Java Virtual Machine.
Property Macros
These macros produce lists or tables containing properties used by the Java platform or jEdit itself.
• Create_Plugin_Announcement.bsh
Creates an announcement for the Plugin Central Submission Tracker based on the plugins *.props
and description.html files.
• Insert_Buffer_Properties.bsh
Inserts buffer-local properties into the current buffer.
If the buffer's mode has a line comment defined, or comment start and end defined, the inserted
properties will be commented out.
• jEdit_Properties.bsh
Writes an unsorted list of jEdit properties in a new buffer.
• Look_and_Feel_Properties.bsh
Writes an unsorted list of the names of Java Look and Feel properties in a new buffer.
• System_Properties.bsh
Writes an unsorted list of all Java system properties in a new buffer.
Text Macros
These macros generate various forms of formatted text.
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Macros Included With jEdit
• Add_Prefix_and_Suffix.bsh
Adds user-supplied “prefix” and “suffix” text to each line in a group of selected lines.
Text is added after leading whitespace and before trailing whitespace. A dialog window receives
input and “remembers” past entries.
• Color_Picker.bsh
Displays a color picker and inserts the selected color in hexadecimal format, prefixed with a “#”.
• Compose_Tag.bsh
The selection is taken as tag name and replaced with a full xml tag.
• Duplicate_Line.bsh
Duplicates the line on which the caret lies immediately beneath it and moves the caret to the new
line.
• Insert_Date.bsh
Inserts the current date and time in the current buffer.
The inserted text includes a representation of the time in the “Internet Time” format.
• Insert_Tag.bsh
Inserts a balanced pair of HTML/SGML/XML markup tags as supplied in an input dialog. The
tags will surround any selected text.
• Line_Filter.bsh
Filters lines of the current buffer due to a provided regular expression. The resulting set of lines
can be either removed from the buffer or written to a new buffer.
The filter works on a multiline selection (if there is one) otherwise on the whole buffer. The
resulting set of lines includes those lines that either match or not match the regular expression.
• Next_Char.bsh
Finds next occurrence of character on current line.
The macro takes the next character typed after macro execution as the character being searched.
That character is not displayed. If the character does not appear in the balance of the current line,
no action occurs.
This macro illustrates the use of InputHandler.readNextChar() as a means of obtaining
user input. See the section called “Using a Single Keypress as Input”.
• Reverse_Lines.bsh
Reverses the selected lines or the entire buffer if no lines are selected. Does not support
Rectangular Selections.
• Single_Space_Buffer.bsh
Removes every second line, if they are all blank.
71
Part II. Writing Edit Modes
This part of the user's guide covers writing edit modes for jEdit.
Edit modes specify syntax highlighting rules, auto indent behavior, and various other customizations for editing
different file types. For general information about edit modes, see the section called “Edit Modes”.
This part of the user's guide was written by Slava Pestov and is maintained by the jEdit core development team.
Chapter 10. Mode Definition Syntax
Edit modes are defined using XML, the eXtensible Markup Language; mode files have the
extension .xml. XML is a very simple language, and as a result edit modes are easy to create and
modify. This section will start with a short XML primer, followed by detailed information about
each supported tag and highlighting rule.
Editing a mode or a mode catalog file within jEdit will cause the changes to take effect immediately.
If you edit modes using another application, the changes will take effect after the Utilities >
Troubleshooting > Reload Edit Modes command is invoked.
An XML Primer
A very simple XML file (which also happens to be an edit mode) looks like so:
<?xml version="1.0"?>
<!DOCTYPE MODE SYSTEM "xmode.dtd">
<MODE>
<PROPS>
<PROPERTY NAME="commentStart" VALUE="/*" />
<PROPERTY NAME="commentEnd" VALUE="*/" />
</PROPS>
<RULES>
<SPAN TYPE="COMMENT1">
<BEGIN>/*</BEGIN>
<END>*/</END>
</SPAN>
</RULES>
</MODE>
Note that each opening tag must have a corresponding closing tag. If there is nothing between the
opening and closing tags, for example <TAG></TAG>, the shorthand notation <TAG /> may be
used. An example of this shorthand can be seen in the <PROPERTY> tags above.
Validation and Errors
Most XML file formats have a formal grammar specified in either DTD, XSD or RNG.
In the example above, we can see that the DOCTYPE, or formal grammar for jEdit mode
files is described in xmode.dtd, which happens to come from jEdit's source code. If
you install the XML plugin, and while editing a mode file in jEdit, go to Plugins - XML Parse as XML, you should see a structure tree in Sidekick, and you will also see errors (if
there are any) in ErrorList, if the document does not conform to the proper XML syntax or
the document's formal grammar. In addition, the XML plugin provides completion tips for
elements and attributes. All of these things can help immensely especially when learning
XML.
It is highly recommended that you check your XML files for validation errors before
submitting them to the community.
XML is case sensitive. Span or span is not the same as SPAN.
To insert a special character such as < or > literally in XML (for example, inside an attribute value),
you must write it as an entity. An entity consists of the character's symbolic name enclosed within
“&” and “;”. The most frequently used entities are:
73
Mode Definition Syntax
• &lt; - The less-than (<) character
• &gt; - The greater-than (>) character
• &amp; - The ampersand (&) character
For example, the following will cause a syntax error:
<SEQ TYPE="OPERATOR">&</SEQ>
Instead, you must write:
<SEQ TYPE="OPERATOR">&amp;</SEQ>
Now that the basics of XML have been covered, the rest of this section will cover each construct in
detail.
The Preamble and MODE tag
Each mode definition must begin with the following:
<?xml version="1.0"?>
<!DOCTYPE MODE SYSTEM "xmode.dtd">
Each mode definition must also contain exactly one MODE tag. All other tags (PROPS, RULES)
must be placed inside the MODE tag. The MODE tag does not have any defined attributes. Here is an
example:
<MODE>
... mode definition goes here ...
</MODE>
The PROPS Tag
The PROPS tag and the PROPERTY tags inside it are used to define mode-specific properties. Each
PROPERTY tag must have a NAME attribute set to the property's name, and a VALUE attribute with
the property's value.
All buffer-local properties listed in the section called “Buffer-Local Properties” may be given values
in edit modes.
contextInsensitive - If true, the property indicates that a line can always be highlighted
without taking care of the previous line. If activated, the syntax parsing will be much faster.
The following mode properties specify commenting strings:
• commentEnd - the comment end string, used by the Range Comment command.
• commentStart - the comment start string, used by the Range Comment command.
• lineComment - the line comment string, used by the Line Comment command.
When performing auto indent, a number of mode properties determine the resulting indent level:
• The line and the one before it are scanned for brackets listed in the indentCloseBrackets
and indentOpenBrackets properties. Opening brackets in the previous line increase indent.
If lineUpClosingBracket is set to true, then closing brackets on the current line will
line up with the line containing the matching opening bracket. For example, in Java mode
lineUpClosingBracket is set to true, resulting in brackets being indented like so:
{
74
Mode Definition Syntax
// Code
{
// More code
}
}
If lineUpClosingBracket is set to false, the line after a closing bracket will be
lined up with the line containing the matching opening bracket. For example, in Lisp mode
lineUpClosingBracket is set to false, resulting in brackets being indented like so:
(foo 'a-parameter
(crazy-p)
(bar baz ()))
(print "hello world")
• If the previous line contains no opening brackets, or if the doubleBracketIndent
property is set to true, the previous line is checked against the regular expressions in the
indentNextLine and indentNextLines properties. If the previous line matches the
former, the indent of the current line is increased and the subsequent line is shifted back again. If
the previous line matches the latter, the indent of the current and subsequent lines is increased.
There are corresponding unindentThisLine and unindentNextLines properties which
are checked also, for doing the reverse-indent operation on lines that match certain regular
expressions.
In Java mode, for example, the indentNextLine property is set to match control structures
such as “if”, “else”, “while”, and so on.
The doubleBracketIndent property, if set to the default of false, results in code indented
like so:
while(objects.hasNext())
{
Object next = objects.hasNext();
if(next instanceof Paintable)
next.paint(g);
}
On the other hand, settings this property to “true” will give the following result:
while(objects.hasNext())
{
Object next = objects.hasNext();
if(next instanceof Paintable)
next.paint(g);
}
• electricKeys: characters listed here, when typed on a line, cause the current line to be reindented. Notice that by default, pressing "Enter" does not re-indent the current line, only the new
line. To get this behavior, add the newline character to electricKeys in the xml-escaped form
&#xA;
• ignoreWhitespace: Ignore whitespace lines. This property is on (true) by default. Python
language sets this to false because of the special treatment of whitespaces. Note this example:
def fun1:
a = 1
b = 2
def fun2:
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Mode Definition Syntax
Pressing C+i (Indent Lines command) on the fun2 line would usually indent this line and make
it even with the b = 2 line. But with switched off ignoreWhitespace setting the line will
stay the way it was indented manually. ignoreWhitespace=false setting prevents any
forward indentation after a whitespace line.
Here is the complete <PROPS> tag for Java mode:
<PROPS>
<PROPERTY
<PROPERTY
<PROPERTY
<PROPERTY
NAME="commentStart" VALUE="/*" />
NAME="commentEnd" VALUE="*/" />
NAME="lineComment" VALUE="//" />
NAME="wordBreakChars" VALUE=",+-=&lt;&gt;/?^&amp;*" />
<!-- Auto indent -->
<PROPERTY NAME="indentOpenBrackets" VALUE="{" />
<PROPERTY NAME="indentCloseBrackets" VALUE="}" />
<PROPERTY NAME="unalignedOpenBrackets" VALUE="(" />
<PROPERTY NAME="unalignedCloseBrackets" VALUE=")" />
<PROPERTY NAME="indentNextLine"
VALUE="\s*(((if|while)\s*\(|else\s*|else\s+if\s*\(|for\s*\(.*\))[^{;]*)" />
<PROPERTY NAME="unindentThisLine"
VALUE="^.*(default:\s*|case.*:.*)$" />
<PROPERTY NAME="electricKeys" VALUE=":" />
<!-- set this to 'true' if you want to use GNU coding style -->
<PROPERTY NAME="doubleBracketIndent" VALUE="false" />
<PROPERTY NAME="lineUpClosingBracket" VALUE="true" />
</PROPS>
The RULES Tag
RULES tags must be placed inside the MODE tag. Each RULES tag defines a ruleset. A ruleset
consists of a number of parser rules, with each parser rule specifying how to highlight a specific
syntax token. There must be at least one ruleset in each edit mode. There can also be more than one,
with different rulesets being used to highlight different parts of a buffer (for example, in HTML
mode, one rule set highlights HTML tags, and another highlights inline JavaScript). For information
about using more than one ruleset, see the section called “The SPAN Tag”.
The RULES tag supports the following attributes, all of which are optional:
• SET - the name of this ruleset. All rulesets other than the first must have a name.
• IGNORE_CASE - if set to FALSE, matches will be case sensitive. Otherwise, case will not
matter. Default is TRUE.
• ESCAPE - specifies a character sequence for escaping literals. The first character following the
escape sequence is not considered as input for syntax highlighting, thus being highlighted with
default token for the rule set.
• NO_WORD_SEP - any non-alphanumeric character not in this list is treated as a word separator
for the purposes of syntax highlighting.
• DEFAULT - the token type for text which doesn't match any specific rule. Default is NULL. See
the section called “Token Types” for a list of token types.
• HIGHLIGHT_DIGITS
• DIGIT_RE - see below for information about these two attributes.
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Mode Definition Syntax
Here is an example RULES tag:
<RULES IGNORE_CASE="FALSE" HIGHLIGHT_DIGITS="TRUE">
... parser rules go here ...
</RULES>
Highlighting Numbers
If the HIGHLIGHT_DIGITS attribute is set to TRUE, jEdit will attempt to highlight numbers in
this ruleset.
Any word consisting entirely of digits (0-9) will be highlighted with the DIGIT token type. A word
that contains other letters in addition to digits will be highlighted with the DIGIT token type only
if it matches the regular expression specified in the DIGIT_RE attribute. If this attribute is not
specified, it will not be highlighted.
Here is an example DIGIT_RE regular expression that highlights Java-style numeric literals
(normal numbers, hexadecimals prefixed with 0x, numbers suffixed with various type indicators,
and floating point literals containing an exponent). Note that newlines have been inserted here for
readability.
DIGIT_RE="(0[lL]?|[1-9]\d{0,9}(\d{0,9}[lL])?
|0[xX]\p{XDigit}{1,8}(\p{XDigit}{0,8}[lL])?
|0[0-7]{1,11}([0-7]{0,11}[lL])?|([0-9]+\.[0-9]*
|\.[0-9]+)([eE][+-]?[0-9]+)?[fFdD]?|[0-9]+([eE][+-]?[0-9]+[fFdD]?
|([eE][+-]?[0-9]+)?[fFdD]))"
Regular expression syntax is described in Appendix E, Regular Expressions.
Rule Ordering Requirements
You might encounter this very common pitfall when writing your own modes.
Since jEdit checks buffer text against parser rules in the order they appear in the ruleset, more
specific rules must be placed before generalized ones, otherwise the generalized rules will catch
everything.
This is best demonstrated with an example. The following is incorrect rule ordering:
<SPAN TYPE="MARKUP">
<BEGIN>[</BEGIN>
<END>]</END>
</SPAN>
<SPAN TYPE="KEYWORD1">
<BEGIN>[!</BEGIN>
<END>]</END>
</SPAN>
If you write the above in a rule set, any occurrence of “[” (even things like “[!DEFINE”, etc) will
be highlighted using the first rule, because it will be the first to match. This is most likely not the
intended behavior.
The problem can be solved by placing the more specific rule before the general one:
<SPAN TYPE="KEYWORD1">
<BEGIN>[!</BEGIN>
<END>]</END>
</SPAN>
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Mode Definition Syntax
<SPAN TYPE="MARKUP">
<BEGIN>[</BEGIN>
<END>]</END>
</SPAN>
Now, if the buffer contains the text “[!SPECIAL]”, the rules will be checked in order, and the first
rule will be the first to match. However, if you write “[FOO]”, it will be highlighted using the
second rule, which is exactly what you would expect.
Per-Ruleset Properties
The PROPS tag (described in the section called “The PROPS Tag”) can also be placed inside the
RULES tag to define ruleset-specific properties. The following properties can be set on a per-ruleset
basis:
• commentEnd - the comment end string.
• commentStart - the comment start string.
• lineComment - the line comment string.
This allows different parts of a file to have different comment strings (in the case of HTML, for
example, in HTML text and inline JavaScript). For information about the commenting commands,
see the section called “Commenting Out Code”.
The TERMINATE Tag
The TERMINATE rule, which must be placed inside a RULES tag, specifies that parsing should stop
after the specified number of characters have been read from a line. The number of characters to
terminate after should be specified with the AT_CHAR attribute. Here is an example:
<TERMINATE AT_CHAR="1" />
This rule is used in Patch mode, for example, because only the first character of each line affects
highlighting.
The SPAN Tag
The SPAN rule, which must be placed inside a RULES tag, highlights text between a start and end
string. The start and end strings are specified inside child elements of the SPAN tag. The following
attributes are supported:
• TYPE - The token type to highlight the span with. See the section called “Token Types” for a list
of token types.
• AT_LINE_START - If set to TRUE, the span will only be highlighted if the start sequence occurs
at the beginning of a line.
• AT_WHITESPACE_END - If set to TRUE, the span will only be highlighted if the start sequence
is the first non-whitespace text in the line.
• AT_WORD_START - If set to TRUE, the span will only be highlighted if the start sequence occurs
at the beginning of a word.
• DELEGATE - text inside the span will be highlighted with the specified ruleset. To delegate to
a ruleset defined in the current mode, just specify its name. To delegate to a ruleset defined in
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Mode Definition Syntax
another mode, specify a name of the form mode::ruleset. Note that the first (unnamed)
ruleset in a mode is called “MAIN”.
• MATCH_TYPE - Controls how the start and end of the sequence will be highlighted. See the
section called “The MATCH_TYPE Attribute” for more information.
• ESCAPE - specifies a character sequence for escaping characters. The first character following
the escape sequence is not considered as input for syntax highlighting, thus being highlighted
with rule's token.
• NO_LINE_BREAK - If set to TRUE, the span will not cross line breaks.
• NO_WORD_BREAK - If set to TRUE, the span will not cross word breaks.
Note that the AT_LINE_START, AT_WHITESPACE_END and AT_WORD_START attributes can
also be used on the END element.
Here is a SPAN that highlights Java string literals, which cannot include line breaks:
<SPAN TYPE="LITERAL1" NO_LINE_BREAK="TRUE">
<BEGIN>"</BEGIN>
<END>"</END>
</SPAN>
Here is a SPAN that highlights Java documentation comments by delegating to the “JAVADOC”
ruleset defined elsewhere in the current mode:
<SPAN TYPE="COMMENT2" DELEGATE="JAVADOC">
<BEGIN>/**</BEGIN>
<END>*/</END>
</SPAN>
Here is a SPAN that highlights HTML cascading stylesheets inside <STYLE> tags by delegating to
the main ruleset in the CSS edit mode:
<SPAN TYPE="MARKUP" DELEGATE="css::MAIN">
<BEGIN>&lt;style&gt;</BEGIN>
<END>&lt;/style&gt;</END>
</SPAN>
The SPAN_REGEXP Tag
The SPAN_REGEXP rule is similar to the SPAN rule except the start sequence and optionally the
end sequence are taken to be regular expressions. In addition to the attributes supported by the
SPAN tag, the following attributes are supported:
• HASH_CHAR - a literal string which must be at the start of a regular expression.
• HASH_CHARS - a list of possible literal characters, one of which must match at the start of the
regular expression.
HASH_CHAR and HASH_CHARS attributes are both optional, but you may only specify one, not
both. If both are specified, HASH_CHARS is ignored and an error is shown. Whenever possible,
use a literal prefix to specify a SPAN_REGEXP. If the starting prefix is always the same, use
HASH_CHAR and provide as much prefix as possible. Only in rare cases would you omit both
attributes, such as the case where there is no other reliable way to get the highlighting you need, for
example, with comments in the Cobol programming language.
In addition, the END subtag supports the attribute REGEXP, which if set to TRUE, tells the
highlighter to interpret the END text as a regular expression as well.
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Mode Definition Syntax
The regular expression match cannot span more than one line. Any text matched by groups in the
BEGIN regular expression is substituted in the END string. See below for an example of where this
is useful.
Regular expression syntax is described in Appendix E, Regular Expressions.
Here is a SPAN_REGEXP rule that highlights “read-ins” in shell scripts:
<SPAN_REGEXP HASH_CHAR="&lt;" TYPE="LITERAL1" DELEGATE="LITERAL">
<BEGIN><![CDATA[<<[\p{Space}'"]*([\p{Alnum}_]+)[\p{Space}'"]*]]></BEGIN>
<END>$1</END>
</SPAN_REGEXP>
Here is a SPAN_REGEXP rule that highlights constructs placed between <#ftl and >, as long as
the <#ftl is followed by a word break:
<SPAN_REGEXP TYPE="KEYWORD1" HASH_CHAR="&lt;" DELEGATE="EXPRESSION">
<BEGIN>&lt;#ftl\b</BEGIN>
<END>&gt;</END>
</SPAN_REGEXP>
The EOL_SPAN Tag
An EOL_SPAN is similar to a SPAN except that highlighting stops at the end of the line, and no
end sequence needs to be specified. The text to match is specified between the opening and closing
EOL_SPAN tags. The following attributes are supported:
• TYPE - The token type to highlight the span with. See the section called “Token Types” for a list
of token types.
• AT_LINE_START - If set to TRUE, the span will only be highlighted if the start sequence occurs
at the beginning of a line.
• AT_WHITESPACE_END - If set to TRUE, the span will only be highlighted if the sequence is the
first non-whitespace text in the line.
• AT_WORD_START - If set to TRUE, the span will only be highlighted if the start sequence occurs
at the beginning of a word.
• DELEGATE - text inside the span will be highlighted with the specified ruleset. To delegate to
a ruleset defined in the current mode, just specify its name. To delegate to a ruleset defined in
another mode, specify a name of the form mode::ruleset. Note that the first (unnamed)
ruleset in a mode is called “MAIN”.
• MATCH_TYPE - Controls how the start of the sequence will be highlighted. See the section called
“The MATCH_TYPE Attribute” for more information.
Here is an EOL_SPAN that highlights C++ comments:
<EOL_SPAN TYPE="COMMENT1">//</EOL_SPAN>
The EOL_SPAN_REGEXP Tag
The EOL_SPAN_REGEXP rule is similar to the EOL_SPAN rule except the match sequence is
taken to be a regular expression. In addition to the attributes supported by the EOL_SPAN tag, the
following attributes are supported:
• HASH_CHAR - a literal string which must be at the start of a regular expression.
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Mode Definition Syntax
• HASH_CHARS - a list of possible literal characters, one of which must match at the start of the
regular expression.
HASH_CHAR and HASH_CHARS attributes are both optional, but you may only specify one, not
both. If both are specified, HASH_CHARS is ignored and an error is shown. Whenever possible,
use a literal prefix to specify a EOL_SPAN_REGEXP. If the starting prefix is always the same,
use HASH_CHAR and provide as much prefix as possible. Only in rare cases would you omit both
attributes, such as the case where there is no other reliable way to get the highlighting you need, for
example, with comments in the Cobol programming language.
The regular expression match cannot span more than one line.
Regular expression syntax is described in Appendix E, Regular Expressions.
Here is an EOL_SPAN_REGEXP that highlights MS-DOS batch file comments, which start with
REM, followed by any whitespace character, and extend until the end of the line:
<EOL_SPAN_REGEXP AT_WHITESPACE_END="TRUE" HASH_CHAR="REM" TYPE="COMMENT1">REM\s<
The MARK_PREVIOUS Tag
The MARK_PREVIOUS rule, which must be placed inside a RULES tag, highlights from the end of
the previous syntax token to the matched text. The text to match is specified between opening and
closing MARK_PREVIOUS tags. The following attributes are supported:
• TYPE - The token type to highlight the text with. See the section called “Token Types” for a list
of token types.
• AT_LINE_START - If set to TRUE, the sequence will only be highlighted if it occurs at the
beginning of a line.
• AT_WHITESPACE_END - If set to TRUE, the sequence will only be highlighted if it is the first
non-whitespace text in the line.
• AT_WORD_START - If set to TRUE, the sequence will only be highlighted if it occurs at the
beginning of a word.
• MATCH_TYPE - Controls how the matched region will be highlighted. See the section called
“The MATCH_TYPE Attribute” for more information.
Here is a rule that highlights labels in Java mode (for example, “XXX:”):
<MARK_PREVIOUS AT_WHITESPACE_END="TRUE"
MATCH_TYPE="DEFAULT">:</MARK_PREVIOUS>
The MARK_FOLLOWING Tag
The MARK_FOLLOWING rule, which must be placed inside a RULES tag, highlights from the start
of the match to the next syntax token. The text to match is specified between opening and closing
MARK_FOLLOWING tags. The following attributes are supported:
• TYPE - The token type to highlight the text with. See the section called “Token Types” for a list
of token types.
• AT_LINE_START - If set to TRUE, the sequence will only be highlighted if it occurs at the
beginning of a line.
• AT_WHITESPACE_END - If set to TRUE, the sequence will only be highlighted if it is the first
non-whitespace text in the line.
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Mode Definition Syntax
• AT_WORD_START - If set to TRUE, the sequence will only be highlighted if it occurs at the
beginning of a word.
• MATCH_TYPE - Controls how the matched region will be highlighted. See the section called
“The MATCH_TYPE Attribute” for more information.
Here is a rule that highlights variables in Unix shell scripts (“$CLASSPATH”, “$IFS”, etc):
<MARK_FOLLOWING TYPE="KEYWORD2">$</MARK_FOLLOWING>
The SEQ Tag
The SEQ rule, which must be placed inside a RULES tag, highlights fixed sequences of text. The
text to highlight is specified between opening and closing SEQ tags. The following attributes are
supported:
• TYPE - the token type to highlight the sequence with. See the section called “Token Types” for a
list of token types.
• AT_LINE_START - If set to TRUE, the sequence will only be highlighted if it occurs at the
beginning of a line.
• AT_WHITESPACE_END - If set to TRUE, the sequence will only be highlighted if it is the first
non-whitespace text in the line.
• AT_WORD_START - If set to TRUE, the sequence will only be highlighted if it occurs at the
beginning of a word.
• DELEGATE - if this attribute is specified, all text after the sequence will be highlighted using this
ruleset. To delegate to a ruleset defined in the current mode, just specify its name. To delegate to
a ruleset defined in another mode, specify a name of the form mode::ruleset. Note that the
first (unnamed) ruleset in a mode is called “MAIN”.
The following rules highlight a few Java operators:
<SEQ
<SEQ
<SEQ
<SEQ
TYPE="OPERATOR">+</SEQ>
TYPE="OPERATOR">-</SEQ>
TYPE="OPERATOR">*</SEQ>
TYPE="OPERATOR">/</SEQ>
The SEQ_REGEXP Tag
The SEQ_REGEXP rule is similar to the SEQ rule except the match sequence is taken to be a regular
expression. In addition to the attributes supported by the SEQ tag, the following attributes are
supported:
• HASH_CHAR - a literal string which must be at the start of a regular expression.
• HASH_CHARS - a list of possible literal characters, one of which must match at the start of the
regular expression.
HASH_CHAR and HASH_CHARS attributes are both optional, but you may only specify one, not
both. If both are specified, HASH_CHARS is ignored and an error is shown. Whenever possible,
use a literal prefix to specify a SEQ_REGEXP. If the starting prefix is always the same, use
HASH_CHAR and provide as much prefix as possible. Only in rare cases would you omit both
attributes, such as the case where there is no other reliable way to get the highlighting you need, for
example, with comments in the Cobol programming language.
The regular expression match cannot span more than one line.
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Mode Definition Syntax
Regular expression syntax is described in Appendix E, Regular Expressions.
NOTE: c-style character escaping for literals (such as the tab char: \t) do not work as attribute
values in XML. Use the XML character entity instead. For example: &#09; instead of \t.
Here is a SEQ_REGEXP rule from moin.xml that uses the HASH_CHARS attribute, to describe a
keyword (wikiword) that can start with any uppercase letter and contain lower case letters and at
least one uppercase letter in the middle.
<SEQ_REGEXP HASH_CHARS="ABCDEFGHIJKLMNOPQRSTUVWXYZ" AT_WORD_START="TRUE"
TYPE="KEYWORD2">[A-Z][a-z]+[A-Z][a-zA-Z]+</SEQ_REGEXP>
The IMPORT Tag
The IMPORT tag, which must be placed inside a RULES tag, loads all rules defined in a given
ruleset into the current ruleset; in other words, it has the same effect as copying and pasting the
imported ruleset.
The only required attribute DELEGATE must be set to the name of a ruleset. To import a ruleset
defined in the current mode, just specify its name. To import a ruleset defined in another mode,
specify a name of the form mode::ruleset. Note that the first (unnamed) ruleset in a mode is
called “MAIN”.
One quirk is that the definition of the imported ruleset is not copied to the location of the IMPORT
tag, but rather to the end of the containing ruleset. This has implications with rule-ordering; see the
section called “Rule Ordering Requirements”.
Here is an example from the PHP mode, which extends the inline JavaScript highlighting to support
embedded PHP:
<RULES SET="JAVASCRIPT+PHP">
<SPAN TYPE="MARKUP" DELEGATE="php::PHP">
<BEGIN>&lt;?php</BEGIN>
<END>?&gt;</END>
</SPAN>
<SPAN TYPE="MARKUP" DELEGATE="php::PHP">
<BEGIN>&lt;?</BEGIN>
<END>?&gt;</END>
</SPAN>
<SPAN TYPE="MARKUP" DELEGATE="php::PHP">
<BEGIN>&lt;%=</BEGIN>
<END>%&gt;</END>
</SPAN>
<IMPORT DELEGATE="javascript::MAIN"/>
</RULES>
The KEYWORDS Tag
The KEYWORDS tag, which must be placed inside a RULES tag and can only appear once, specifies
a list of keywords to highlight. Keywords are similar to SEQs, except that SEQs match anywhere
83
Mode Definition Syntax
in the text, whereas keywords only match whole words. Words are considered to be runs of text
separated by non-alphanumeric characters.
The KEYWORDS tag does not define any attributes.
Each child element of the KEYWORDS tag is an element whose name is a token type, and whose
content is the keyword to highlight. For example, the following rule highlights the most common
Java keywords:
<KEYWORDS>
<KEYWORD1>if</KEYWORD1>
<KEYWORD1>else</KEYWORD1>
<KEYWORD3>int</KEYWORD3>
<KEYWORD3>void</KEYWORD3>
</KEYWORDS>
Token Types
The various token types are used to syntax highlight particular words in a language. This makes
code easier to read. There is a wide latitude in the usage of the token types, and really it depends
on the specifics of the language as to which token represents which type. Some examples are given
below, but these are just guidelines, not hard and fast rules.
Many languages include constructs from other languages. One common example is html files
can include javascript and css blocks. Several of the mode tags support a DELEGATE attribute,
which will allow a section of text to be passed to a different mode for highlighting. The html mode
delegates to the javascript mode for javascript blocks and to the css mode for style blocks. Use of
the DELEGATE attribute is highly encouraged when appropriate since it makes writing modes
easier, reduces duplication, and promotes visual consistency across languages.
Parser rules can highlight tokens using any of the following token types:
• NULL - no special highlighting is performed on tokens of type NULL
• COMMENT1
• COMMENT2
• COMMENT3
• COMMENT4
jEdit supports four different types of comment tokens. Generally, comments are programmerreadable constructs that are ignored by compilers and interpreters. As an example, the lisp mode
defines four comment types:
<EOL_SPAN TYPE="COMMENT4">;;;;</EOL_SPAN>
<EOL_SPAN TYPE="COMMENT3">;;;</EOL_SPAN>
<EOL_SPAN TYPE="COMMENT2">;;</EOL_SPAN>
<EOL_SPAN TYPE="COMMENT1">;</EOL_SPAN>
• FUNCTION
The function token is intended to identify functions, methods, procedures, routines, or named
subprograms.
• DIGIT
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Mode Definition Syntax
The digit token is to identify numbers.
• INVALID
The invalid type is to indicate that particular words are not to be used, for example, the java
mode defined both "goto" and "const" as invalid words. These are words that are defined by the
language, but are not to be used.
• KEYWORD1
• KEYWORD2
• KEYWORD3
• KEYWORD4
Keywords are used to identify well-defined words within a language. Some languages naturally
divide keywords into groups, for example, the pascal mode identifies "for" as a KEYWORD1,
"private" as a KEYWORD2, and "int" as a KEYWORD3.
• LABEL
A label is generally a named position within a source, for example, the ada mode defined a label
as <<foo>>.
• LITERAL1
• LITERAL2
• LITERAL3
• LITERAL4
Literals are usually, but not always, uninterpreted strings, for example, "foo" or 'bar'. There are a
wide variety of usages of literals in the mode files.
• MARKUP
The markup token is generally used in the various "markup" languages, such as xml and html.
Markup is used for those elements that are not specified as words belonging to the language. For
example, in html, <body> would be considered a keyword, where <foo> would be considered
markup.
• OPERATOR
Common examples of operators are the math symbols, such as '+', '-', and so on.
The MATCH_TYPE Attribute
The MATCH_TYPE attribute is used by some of the rules to control how the region matched by the
rule will be highlighted.
For example, when using a MARK_PREVIOUS rule to highlight a function call of the form
fcall(), the following rule could be used:
<MARK_PREVIOUS TYPE="FUNCTION" MATCH_TYPE="OPERATOR">(</MARK_PREVIOUS>
This would cause fcall to be highlighted as FUNCTION, and ( to be highlighted as OPERATOR.
In this case, to maintain bracket matching working, a SEQ rule would have to be added to match )
and mark it as OPERATOR.
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Mode Definition Syntax
The MATCH_TYPE attribute value can be any of the valid token types, or the following special
values:
• RULE: this is the default value. It tells the syntax system to use the same token type as the TYPE
attribute of the rule. This is equivalent to EXCLUDE_MATCH="FALSE" in 4.2 and earlier mode
files.
• CONTEXT: using this value tells the syntax system to mark the matched region using the
default token type for the current rule set. In 4.2 and earlier mode files, this was specified by
EXCLUDE_MATCH="TRUE".
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Chapter 11. Installing Edit Modes
The easiest way to install a new mode locally is to use the Editing dialog found under Utilities Global Options. At the bottom of this dialog is an "Add Mode" button. Clicking this button shows
a dialog to add a mode to jEdit. Simply fill in the blanks and the mode file will be put in the proper
place and the catalog file will be updated appropriately. Modes added this way can be removed by
selecting the mode in the Editing dialog, then clicking the "Delete Mode" button. This button will
only appear for modes that exist in the user settings directory. Core modes, that is, those modes
distributed with jEdit cannot be deleted this way. The details of adding a mode by hand are below.
jEdit looks for edit modes in two locations; the modes subdirectory of the jEdit settings directory,
and the modes subdirectory of the jEdit install directory. The location of the settings directory is
system-specific; see the section called “The jEdit Settings Directory”.
Each mode directory contains a catalog file. All edit modes contained in that directory must be
listed in the catalog, otherwise they will not be available to jEdit.
Catalogs, like modes themselves, are written in XML. They consist of a single MODES tag, with
a number of MODE tags inside. Each mode tag associates a mode name with an XML file, and
specifies the file name and first line pattern for the mode. A sample mode catalog looks as follows:
<?xml version="1.0"?>
<!DOCTYPE CATALOG SYSTEM "catalog.dtd">
<MODES>
<MODE NAME="shellscript" FILE="shellscript.xml"
FILE_NAME_GLOB="*.sh"
FIRST_LINE_GLOB="#!/*sh*" />
</MODES>
In the above example, a mode named “shellscript” is defined, and is used for files whose names end
with .sh, or whose first line starts with “#!/” and contains “sh”.
The MODE tag supports the following attributes:
• NAME - the name of the edit mode, as it will appear in the Buffer Options dialog box, the status
bar, and so on.
• FILE - the name of the XML file containing the mode definition.
• FILE_NAME_GLOB - files whose names match this glob pattern will be opened in this edit
mode. This can also specify full paths, if the glob pattern contains a path separator character.
FILE_NAME_GLOB can be specified in the modes/catalog file, or the mode file itself. See
the FILE_NAME_GLOB for apacheconf.xml in modes/catalog for an example of full
path filename globbing.
• FIRST_LINE_GLOB - files whose first line matches this glob pattern will be opened in this edit
mode.
Glob pattern syntax is described in Appendix D, Glob Patterns.
Tip
If an edit mode in the user-specific catalog has the same name as an edit mode in the
system catalog, the version in the user-specific catalog will override the system default.
When a buffer is opened, jEdit must choose an edit mode for that buffer. It checks conditions in this
order to decide which edit mode to use:
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Installing Edit Modes
1. the filename is an exact match for the FILE_NAME_GLOB.
2. the filename matches the FILE_NAME_GLOB and the first line of the file matches the
FIRST_LINE_GLOB
3. the filename matches the FILE_NAME_GLOB
4. the first line of the file matches the FIRST_LINE_GLOB
88
Chapter 12. Updating Edit Modes
From jEdit 4.2 to 4.4
1. All regular expressions in mode files were rewritten to use java.util.regex instead of gnu.regexp.
2. HASH_CHAR handling of xxx_REGEXP elements has been updated, as explained in the section
called “The SPAN_REGEXP Tag”.
3. The EXCLUDE_MATCH attribute got superseded by MATCH_TYPE. The attribute values translate
from TRUE to CONTEXT and from FALSE to RULE, respectively. For more information see the
section called “The MATCH_TYPE Attribute”.
4. NO_ESCAPE is now deprecated and ignored by the parsing engine. ESCAPE is now a valid
attribute for SPAN and SPAN_REGEXP rules.
89
Part III. Writing Macros
This part of the user's guide covers writing macros for jEdit.
First, we will tell you a little about BeanShell, jEdit's macro scripting language. Next, we will walk through a
few simple macros. We then present and analyze a dialog-based macro to illustrate additional macro writing
techniques. Finally, we discuss several tips and techniques for writing and debugging macros.
Chapter 13. Macro Basics
Introducing BeanShell
Here is how BeanShell's author, Pat Niemeyer, describes his creation:
“BeanShell is a small, free, embeddable, Java source interpreter with object
scripting language features, written in Java. BeanShell executes standard Java
statements and expressions, in addition to obvious scripting commands and
syntax. BeanShell supports scripted objects as simple method closures like those
in Perl and JavaScript.”
You do not have to know anything about Java to begin writing your own jEdit macros. But if
you know how to program in Java, you already know how to write BeanShell scripts. The major
strength of using BeanShell with a program written in Java is that it allows the user to customize the
program's behavior using the same interfaces designed and used by the program itself. BeanShell
can turn a well-designed application into a powerful, extensible toolkit.
This guide focuses on using BeanShell in macros. If you are interested in learning more about
BeanShell generally, consult the BeanShell web site. Information on how to run and organize
macros, whether included with the jEdit installation or written by you, can be found in Chapter 8,
Using Macros.
Single Execution Macros
As noted in the section called “How jEdit Organizes Macros”, you can save a BeanShell script of
any length as a text file with the .bsh extension and run it from the Macros menu. There are three
other ways jEdit lets you use BeanShell quickly, without saving a script to storage, on a “one time
only” basis. You will find them in the Utilities menu.
Utilities>BeanShell>Evaluate BeanShell Expression displays a text input dialog that asks you to
type a single line of BeanShell commands. You can type more than one BeanShell statement so long
as each of them ends with a semicolon. If BeanShell successfully interprets your input, a message
box will appear with the return value of the last statement.
Utilities>BeanShell>Evaluate For Selected Lines displays a text input dialog that asks you to type
a single line of BeanShell commands. The commands are evaluated for each line of the selection.
In addition to the standard set of variables described in the section called “Predefined Variables in
BeanShell”, this command defines the following:
• line - the line number, from the start of the buffer. The first line is numbered 0.
• index - the line number, from the start of the selection. The first line is numbered 0.
• text - the text of the line.
Try typing an expression like (line + 1) + ": " + text in the Evaluate For Selected
Lines dialog box. This will add a line number to each selected line beginning with the number 1.
The BeanShell expression you enter will be evaluated and substituted in place of the entire text of a
selected line. If you want to leave the line's current text as an element of the modified line, you must
include the defined variable text as part of the BeanShell expression that you enter.
Utilities>BeanShell>Evaluate Selection evaluates the selected text as a BeanShell script and
replaces it with the return value of the statement.
Using Evaluate Selection is an easy way to do arithmetic calculations inline while editing.
BeanShell uses numbers and arithmetic operations in an ordinary, intuitive way.
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Macro Basics
Try typing an expression like (3745*856)+74 in the buffer, select it, and choose
Utilities>BeanShell>Evaluate Selection. The selected text will be replaced by the answer,
3205794.
Console plugin
You can also do the same thing using the BeanShell interpreter option of the Console plugin.
The Mandatory First Example
Macros.message(view, "Hello world!");
Running this one line script causes jEdit to display a message box (more precisely, a
JOptionPane object) with the traditional beginner's message and an OK button. Let's see what is
happening here.
This statement calls a static method (or function) named message in jEdit's Macros class. If you
don't know anything about classes or static methods or Java (or C++, which employs the same
concept), you will need to gain some understanding of a few terms. Obviously this is not the place
for academic precision, but if you are entirely new to object-oriented programming, here are a few
skeleton ideas to help you with BeanShell.
• An object is a collection of data that can be initialized, accessed and manipulated in certain
defined ways.
• A class is a specification of what data an object contains and what methods can be used to work
with the data. A Java application consists of one or more classes (in the case of jEdit ,over 600
classes) written by the programmer that defines the application's behavior. A BeanShell macro
uses these classes, along with built-in classes that are supplied with the Java platform, to define
its own behavior.
• A subclass (or child class) is a class which uses (or “inherits”) the data and methods of its parent
class along with additions or modifications that alter the subclass's behavior. Classes are typically
organized in hierarchies of parent and child classes to organize program code, to define common
behavior in shared parent class code, and to specify the types of similar behavior that child classes
will perform in their own specific ways.
• A method (or function) is a procedure that works with data in a particular object, other data
(including other objects) supplied as parameters, or both. Methods typically are applied to a
particular object which is an instance of the class to which the method belongs.
• A static method differs from other methods in that it does not deal with the data in a particular
object but is included within a class for the sake of convenience.
Java has a rich set of classes defined as part of the Java platform. Like all Java applications, jEdit is
organized as a set of classes that are themselves derived from the Java platform's classes. We will
refer to Java classes and jEdit classes to make this distinction. Some of jEdit's classes (such as those
dealing with regular expressions and XML) are derived from or make use of classes in other opensource Java packages. Except for BeanShell itself, we won't be discussing them in this guide.
In our one line script, the static method Macros.message() has two parameters because that
is the way the method is defined in the Macros class. You must specify both parameters when you
call the function. The first parameter, view, is a variable naming the current, active View object.
Information about pre-defined variables can be found in the section called “Predefined Variables in
BeanShell”.
The second parameter, which appears to be quoted text, is a string literal - a sequence of characters
of fixed length and content. Behind the scenes, BeanShell and Java take this string literal and use it
to create a String object. Normally, if you want to create an object in Java or BeanShell, you must
construct the object using the new keyword and a constructor method that is part of the object's
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Macro Basics
class. We'll show an example of that later. However, both Java and BeanShell let you use a string
literal anytime a method's parameter calls for a String.
If you are a Java programmer, you might wonder about a few things missing from this one line
program. There is no class definition, for example. You can think of a BeanShell script as an
implicit definition of a main() method in an anonymous class. That is in fact how BeanShell is
implemented; the class is derived from a BeanShell class called XThis. If you don't find that helpful,
just think of a script as one or more blocks of procedural statements conforming to Java syntax
rules. You will also get along fine (for the most part) with C or C++ syntax if you leave out anything
to do with pointers or memory management - Java and BeanShell do not have pointers and deal with
memory management automatically.
Another missing item from a Java perspective is a package statement. In Java, such a statement
is used to bundle together a number of files so that their classes become visible to one another.
Packages are not part of BeanShell, and you don't need to know anything about them to write
BeanShell macros.
Finally, there are no import statements in this script. In Java, an import statement makes public
classes from other packages visible within the file in which the statement occurs without having to
specify a fully qualified class name. Without an import statement or a fully qualified name, Java
cannot identify most classes using a single name as an identifier.
jEdit automatically imports a number of commonly-used packages into the namespace of every
BeanShell script. Because of this, the script output of a recorded macro does not contain import
statements. For the same reason, most BeanShell scripts you write will not require import
statements.
Java requires import statement to be located at the beginning of a source file. BeanShell allows
you to place import statements anywhere in a script, including inside a block of statements. The
import statement will cover all names used following the statement in the enclosing block.
If you try to use a class that is not imported without its fully-qualified name, the BeanShell
interpreter will complain with an error message relating to the offending line of code.
Here is the full list of packages automatically imported by jEdit:
java.awt
java.awt.event
java.net
java.util
java.io
java.lang
javax.swing
javax.swing.event
org.gjt.sp.jedit
org.gjt.sp.jedit.browser
org.gjt.sp.jedit.buffer
org.gjt.sp.jedit.gui
org.gjt.sp.jedit.help
org.gjt.sp.jedit.io
org.gjt.sp.jedit.msg
org.gjt.sp.jedit.options
org.gjt.sp.jedit.pluginmgr
org.gjt.sp.jedit.print
org.gjt.sp.jedit.search
org.gjt.sp.jedit.syntax
org.gjt.sp.jedit.textarea
org.gjt.sp.util
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Macro Basics
Predefined Variables in BeanShell
The following variables are always available for use in BeanShell scripts:
• buffer - a Buffer object represents the contents of the currently visible open text file.
• view - A View represents the current top-level editor window, extending Java's JFrame class,
that contains the various visible components of the program, including the text area, menu bar,
toolbar, and any docked windows.
This variable has the same value as the return value of:
jEdit.getActiveView()
• editPane - an EditPane object contains a text area and buffer switcher. A view can be split to
display edit panes. Among other things, the EditPane class contains methods for selecting the
buffer to edit.
Most of the time your macros will manipulate the buffer or the textArea. Sometimes you
will need to use view as a parameter in a method call. You will probably only need to use
editPane if your macros work with split views.
This variable has the same value as the return value of:
view.getEditPane()
• textArea - a JEditTextArea is the visible component that displays the current buffer.
This variable has the same value as the return value of:
editPane.getTextArea()
• wm - a DockableWindowManager is the visible component that manages dockable windows in the
current view. This class is discussed in detail in Part IV, “Writing Plugins”. This object is useful
for writing macros that interface with, open, or close plugin windows.
This variable has the same value the return value of:
view.getDockableWindowManager()
• scriptPath - set to the full path of the script currently being executed.
Note that these variables are set at the beginning of macro execution. If the macro switches views,
buffers or edit panes, the variable values will be out of date. In that case, you can use the equivalent
method calls.
Helpful Methods in the Macros Class
Including message(), there are five static methods in the Macros class that allow you to
converse easily with your macros. They all encapsulate calls to methods of the Java platform's
JOptionPane class.
• public static void message(Component comp, String message);
• public static void error(Component comp, String message);
• public static String input(Component comp, String prompt);
• public static String input(Component comp, String prompt, String
defaultValue);
94
Macro Basics
• public static int confirm(Component comp, String prompt, int
buttons);
The format of these four declarations provides a concise reference to the way in which the methods
may be used. The keyword public means that the method can be used outside the Macros class.
The alternatives are private and protected. For purposes of BeanShell, you just have to know
that BeanShell can only use public methods of other Java classes. The keyword static we have
already discussed. It means that the method does not operate on a particular object. You call a static
function using the name of the class (like Macros) rather than the name of a particular object (like
view). The third word is the type of the value returned by the method. The keyword void is Java's
way of saying the the method does not have a return value.
The error() method works just like message() but displays an error icon in the message box.
The input() method furnishes a text field for input, an OK button and a Cancel button. If Cancel
is pressed, the method returns null. If OK is pressed, a String containing the contents of the
text field is returned. Note that there are two forms of the input() method; the first form with two
parameters displays an empty input field, the other forms lets you specify an initial, default input
value.
For those without Java experience, it is important to know that null is not the same as an empty,
“zero-length” String. It is Java's way of saying that there is no object associated with this
variable. Whenever you seek to use a return value from input() in your macro, you should test it
to see if it is null. In most cases, you will want to exit gracefully from the script with a return
statement, because the presence of a null value for an input variable usually means that the user
intended to cancel macro execution. BeanShell will complain if you call any methods on a null
object.
The confirm() method in the Macros class is a little more complex. The buttons parameter
has an int type, and the usual way to supply a value is to use one of the predefined values taken
from Java's JOptionPane class. You can choose among JOptionPane.YES_NO_OPTION,
JOptionPane.YES_NO_CANCEL_OPTION, or JOptionPane.OK_CANCEL_OPTION.
The return value of the method is also an int, and should be tested against the value of other
predefined constants: JOptionPane.YES_OPTION, JOptionPane.NO_OPTION,
JOptionPane.OK_OPTION or JOptionPane.CANCEL_OPTION.
We've looked at using Macros.message(). To use the other methods, you would write
something like the following:
Macros.error(view, "Goodbye, cruel world!");
String result = Macros.input(view, "Type something here.");
String result = Macros.input(view, "When were you born?",
"I don't remember, I was very young at the time");
int result = Macros.confirm(view, "Do you really want to learn"
+ " about BeanShell?",JOptionPane.YES_NO_OPTION);
In the last three examples, placing the word String or int before the variable name result
tells BeanShell that the variable refers to an integer or a String object, even before a particular
value is assigned to the variable. In BeanShell, this declaration of the type of result is not
necessary; BeanShell can figure it out when the macro runs. This can be helpful if you are not
comfortable with specifying types and classes; just use your variables and let BeanShell worry about
it.
Note that macros are not limited to using these methods for presenting a user interface. In fact, fullblown user interfaces using the Java Swing APIs are also possible, and will be covered later on in
Chapter 14, A Dialog-Based Macro.
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Macro Basics
BeanShell Dynamic Typing
Without an explicit type declaration like String result, BeanShell variables can change their
type at runtime depending on the object or data assigned to it. This dynamic typing allows you to
write code like this (if you really wanted to):
// note: no type declaration
result = Macros.input(view, “Type something here.”);
// this is our predefined, current View
result = view;
// this is an “int” (for integer);
// in Java and BeanShell, int is one of a small number
// of “primitive” data types which are not classes
result = 14;
However, if you first declared result to be type String and and then tried these reassignments,
BeanShell would complain. While avoiding explicit type declaration makes writing macro code
simpler, using them can act as a check to make sure you are not using the wrong variable type
of object at a later point in your script. It also makes it easier (if you are so inclined) to take a
BeanShell “prototype” and incorporate it in a Java program.
One last thing before we bury our first macro. The double slashes in the examples just above signify
that everything following them on that line should be ignored by BeanShell as a comment. As in
Java and C/C++, you can also embed comments in your BeanShell code by setting them off with
pairs of /* */, as in the following example:
/* This is a long comment that covers several lines
and will be totally ignored by BeanShell regardless of how
many lines it covers */
Now For Something Useful
Here is a macro that inserts the path of the current buffer in the text:
String newText = buffer.getPath();
textArea.setSelectedText(newText);
Unlike in our first macro example, here we are calling class methods on particular objects. First,
we call getPath() on the current Buffer object to get the full path of the text file currently being
edited. Next, we call setSelectedText() on the current text display component, specifying the
text to be inserted as a parameter.
In precise terms, the setSelectedText() method substitutes the contents of the String
parameter for a range of selected text that includes the current caret position. If no text is selected at
the caret position, the effect of this operation is simply to insert the new text at that position.
Here's a few alternatives to the full file path that you could use to insert various useful things:
// the file name (without full path)
String newText = buffer.getName();
// today's date
import java.text.DateFormat;
String newText = DateFormat.getDateInstance()
.format(new Date());
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Macro Basics
// a line count for the current buffer
String newText = "This file contains "
+ textArea.getLineCount() + " lines.";
Here are brief comments on each:
• In the first, the call to getName() invokes another method of the Buffer class.
• The syntax of the second example chains the results of several methods. You could write it this
way:
import java.text.DateFormat;
Date d = new Date();
DateFormat df = DateFormat.getDateInstance();
String result = df.format(d);
Taking the pieces in order:
• A Java Date object is created using the new keyword. The empty parenthesis after Date
signify a call on the constructor method of Date having no parameters; here, a Date is
created representing the current date and time.
• DateFormat.getDateInstance() is a static method that creates and returns a
DateFormat object. As the name implies, DateFormat is a Java class that takes
Date objects and produces readable text. The method getDateInstance() returns a
DateFormat object that parses and formats dates. It will use the default locale or text format
specified in the user's Java installation.
• Finally, DateFormat.format() is called on the new DateFormat object using the
Date object as a parameter. The result is a String containing the date in the default locale.
• Note that the Date class is contained in the java.util package, so an explicit import
statement is not required. However, DateFormat is part of the java.text package, which
is not automatically imported, so an explicit import statement must be used.
• The third example shows three items of note:
• getLineCount() is a method in jEdit's JEditTextArea class. It returns an int representing
the number of lines in the current text buffer. We call it on textArea, the pre-defined,
current JEditTextArea object.
• The use of the + operator (which can be chained, as here) appends objects and string literals to
return a single, concatenated String.
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Chapter 14. A Dialog-Based Macro
Now we will look at a more complicated macro which will demonstrate some useful techniques and
BeanShell features.
Use of the Macro
Our new example adds prefix and suffix text to a series of selected lines. This macro can be used
to reduce typing for a series of text items that must be preceded and following by identical text. In
Java, for example, if we are interested in making a series of calls to StringBuffer.append()
to construct a lengthy, formatted string, we could type the parameter for each call on successive
lines as follows:
profileString_1
secretThing.toString()
name
address
addressSupp
city
“state/province”
country
Our macro would ask for input for the common “prefix” and “suffix” to be applied to each line; in
this case, the prefix is ourStringBuffer.append( and the suffix is );. After selecting these
lines and running the macro, the resulting text would look like this:
ourStringBuffer.append(profileString_1);
ourStringBuffer.append(secretThing.toString());
ourStringBuffer.append(name);
ourStringBuffer.append(address);
ourStringBuffer.append(addressSupp);
ourStringBuffer.append(city);
ourStringBuffer.append(“state/province”);
ourStringBuffer.append(country);
Listing of the Macro
The macro script follows. You can find it in the jEdit distribution in the Text subdirectory of the
macros directory. You can also try it out by invoking Macros>Text>Add Prefix and Suffix.
// beginning of Add_Prefix_and_Suffix.bsh
// import statement (see the section called “Import Statements”)
import javax.swing.border.*;
// main routine
void prefixSuffixDialog()
{
// create dialog object (see the section called “Create the Dialog”)
title = “Add prefix and suffix to selected lines”;
dialog = new JDialog(view, title, false);
content = new JPanel(new BorderLayout());
content.setBorder(new EmptyBorder(12, 12, 12, 12));
content.setPreferredSize(new Dimension(320, 160));
dialog.setContentPane(content);
// add the text fields (see the section called “Create the Text Fields”)
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A Dialog-Based Macro
fieldPanel = new JPanel(new GridLayout(4, 1, 0, 6));
prefixField = new HistoryTextField(“macro.add-prefix”);
prefixLabel = new JLabel(“Prefix to add:”);
suffixField = new HistoryTextField(“macro.add-suffix”);
suffixLabel = new JLabel(“Suffix to add:”);
fieldPanel.add(prefixLabel);
fieldPanel.add(prefixField);
fieldPanel.add(suffixLabel);
fieldPanel.add(suffixField);
content.add(fieldPanel, “Center”);
// add a panel containing the buttons (see the section called “Create the Bu
buttonPanel = new JPanel();
buttonPanel.setLayout(new BoxLayout(buttonPanel,
BoxLayout.X_AXIS));
buttonPanel.setBorder(new EmptyBorder(12, 50, 0, 50));
buttonPanel.add(Box.createGlue());
ok = new JButton(“OK”);
cancel = new JButton(“Cancel”);
ok.setPreferredSize(cancel.getPreferredSize());
dialog.getRootPane().setDefaultButton(ok);
buttonPanel.add(ok);
buttonPanel.add(Box.createHorizontalStrut(6));
buttonPanel.add(cancel);
buttonPanel.add(Box.createGlue());
content.add(buttonPanel, “South”);
// register this method as an ActionListener for
// the buttons and text fields (see the section called “Register the Action
ok.addActionListener(this);
cancel.addActionListener(this);
prefixField.addActionListener(this);
suffixField.addActionListener(this);
// locate the dialog in the center of the
// editing pane and make it visible (see the section called “Make the Dialog
dialog.pack();
dialog.setLocationRelativeTo(view);
dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
dialog.setVisible(true);
// this method will be called when a button is clicked
// or when ENTER is pressed (see the section called “The Action Listener”)
void actionPerformed(e)
{
if(e.getSource() != cancel)
{
processText();
}
dialog.dispose();
}
// this is where the work gets done to insert
// the prefix and suffix (see the section called “Get the User's Input”)
void processText()
{
prefix = prefixField.getText();
suffix = suffixField.getText();
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A Dialog-Based Macro
if(prefix.length() == 0 && suffix.length() == 0)
return;
prefixField.addCurrentToHistory();
suffixField.addCurrentToHistory();
// text manipulation begins here using calls
// to jEdit methods (see the section called “Call jEdit Methods to Mani
buffer.beginCompoundEdit();
selectedLines = textArea.getSelectedLines();
for(i = 0; i < selectedLines.length; ++i)
{
offsetBOL = textArea.getLineStartOffset(
selectedLines[i]);
textArea.setCaretPosition(offsetBOL);
textArea.goToStartOfWhiteSpace(false);
textArea.goToEndOfWhiteSpace(true);
text = textArea.getSelectedText();
if(text == null) text = "";
textArea.setSelectedText(prefix + text + suffix);
}
buffer.endCompoundEdit();
}
}
// this single line of code is the script's main routine
// (see the section called “The Main Routine”)
prefixSuffixDialog();
// end of Add_Prefix_and_Suffix.bsh
Analysis of the Macro
Import Statements
// import statement
import javax.swing.border.*;
This macro makes use of classes in the javax.swing.border package, which is not
automatically imported. As we mentioned previously (see the section called “The Mandatory First
Example”), jEdit's implementation of BeanShell causes a number of classes to be automatically
imported. Classes that are not automatically imported must be identified by a full qualified name or
be the subject of an import statement.
Create the Dialog
// create dialog object
title = “Add prefix and suffix to selected lines”;
dialog = new JDialog(view, title, false);
content = new JPanel(new BorderLayout());
content.setBorder(new EmptyBorder(12, 12, 12, 12));
dialog.setContentPane(content);
To get input for the macro, we need a dialog that provides for input of the prefix and suffix strings,
an OK button to perform text insertion, and a Cancel button in case we change our mind. We have
decided to make the dialog window non-modal. This will allow us to move around in the text buffer
to find things we may need (including text to cut and paste) while the macro is running and the
dialog is visible.
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A Dialog-Based Macro
The Java object we need is a JDialog object from the Swing package. To construct one, we use
the new keyword and call a constructor function. The constructor we use takes three parameters:
the owner of the new dialog, the title to be displayed in the dialog frame, and a boolean parameter
(true or false) that specifies whether the dialog will be modal or non-modal. We define the
variable title using a string literal, then use it immediately in the JDialog constructor.
A JDialog object is a window containing a single object called a content pane. The content pane
in turn contains the various visible components of the dialog. A JDialog creates an empty content
pane for itself as during its construction. However, to control the dialog's appearance as much as
possible, we will separately create our own content pane and attach it to the JDialog. We do this
by creating a JPanel object. A JPanel is a lightweight container for other components that can
be set to a given size and color. It also contains a layout scheme for arranging the size and position
of its components. Here we are constructing a JPanel as a content pane with a BorderLayout.
We put a EmptyBorder inside it to serve as a margin between the edge of the window and the
components inside. We then attach the JPanel as the dialog's content pane, replacing the dialog's
home-grown version.
A BorderLayout is one of the simpler layout schemes available for container objects like
JPanel. A BorderLayout divides the container into five sections: “North”, “South”, “East”,
“West” and “Center”. Components are added to the layout using the container's add method,
specifying the component to be added and the section to which it is assigned. Building a component
like our dialog window involves building a set of nested containers and specifying the location
of each of their member components. We have taken the first step by creating a JPanel as the
dialog's content pane.
Create the Text Fields
// add the text fields
fieldPanel = new JPanel(new GridLayout(4, 1, 0, 6));
prefixField = new HistoryTextField("macro.add-prefix");
prefixLabel = new JLabel(“Prefix to add”:);
suffixField = new HistoryTextField(“macro.add-suffix”);
suffixLabel = new JLabel(“Suffix to add:”);
fieldPanel.add(prefixLabel);
fieldPanel.add(prefixField);
fieldPanel.add(suffixLabel);
fieldPanel.add(suffixField);
content.add(fieldPanel, “Center”);
Next we shall create a smaller panel containing two fields for entering the prefix and suffix text and
two labels identifying the input fields.
For the text fields, we will use jEdit's HistoryTextField class. It is derived from the Java Swing class
JTextField. This class offers the enhancement of a stored list of prior values used as text input.
When the component has input focus, the up and down keys scroll through the prior values for the
variable.
To create the HistoryTextField objects we use a constructor method that takes a single parameter:
the name of the tag under which history values will be stored. Here we choose names that are not
likely to conflict with existing jEdit history items.
The labels that accompany the text fields are JLabel objects from the Java Swing package. The
constructor we use for both labels takes the label text as a single String parameter.
We wish to arrange these four components from top to bottom, one after the other. To achieve
that, we use a JPanel container object named fieldPanel that will be nested inside the
dialog's content pane that we have already created. In the constructor for fieldPanel, we
assign a new GridLayout with the indicated parameters: four rows, one column, zero spacing
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A Dialog-Based Macro
between columns (a meaningless element of a grid with only one column, but nevertheless a
required parameter) and spacing of six pixels between rows. The spacing between rows spreads
out the four “grid” elements. After the components, the panel and the layout are specified, the
components are added to fieldPanel top to bottom, one “grid cell” at a time. Finally, the
complete fieldPanel is added to the dialog's content pane to occupy the “Center” section of the
content pane.
Create the Buttons
// add the buttons
buttonPanel = new JPanel();
buttonPanel.setLayout(new BoxLayout(buttonPanel,
BoxLayout.X_AXIS));
buttonPanel.setBorder(new EmptyBorder(12, 50, 0, 50));
buttonPanel.add(Box.createGlue());
ok = new JButton(“OK”);
cancel = new JButton(“Cancel”);
ok.setPreferredSize(cancel.getPreferredSize());
dialog.getRootPane().setDefaultButton(ok);
buttonPanel.add(ok);
buttonPanel.add(Box.createHorizontalStrut(6));
buttonPanel.add(cancel);
buttonPanel.add(Box.createGlue());
content.add(buttonPanel, “South”);
To create the dialog's buttons, we follow repeat the “nested container” pattern we used in creating
the text fields. First, we create a new, nested panel. This time we use a BoxLayout that places
components either in a single row or column, depending on the parameter passed to its constructor.
This layout object is more flexible than a GridLayout in that variable spacing between elements
can be specified easily. We put an EmptyBorder in the new panel to set margins for placing the
buttons. Then we create the buttons, using a JButton constructor that specifies the button text.
After setting the size of the OK button to equal the size of the Cancel button, we designate the OK
button as the default button in the dialog. This causes the OK button to be outlined when the dialog
if first displayed. Finally, we place the buttons side by side with a 6 pixel gap between them (for
aesthetic reasons), and place the completed buttonPanel in the “South” section of the dialog's
content pane.
Register the Action Listeners
// register this method as an ActionListener for
// the buttons and text fields
ok.addActionListener(this);
cancel.addActionListener(this);
prefixField.addActionListener(this);
suffixField.addActionListener(this);
In order to specify the action to be taken upon clicking a button or pressing the Enter key, we
must register an ActionListener for each of the four active components of the dialog - the two
HistoryTextField components and the two buttons. In Java, an ActionListener is an interface
- an abstract specification for a derived class to implement. The ActionListener interface
contains a single method to be implemented:
public void actionPerformed(ActionEvent e);
BeanShell does not permit a script to create derived classes. However, BeanShell offers a
useful substitute: a method can be used as a scripted object that can include nested methods
implementing a number of Java interfaces. The method prefixSuffixDialog() that
we are writing can thus be treated as an ActionListener object. To accomplish this, we
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A Dialog-Based Macro
call addActionListener() on each of the four components specifying this as the
ActionListener. We still need to implement the interface. We will do that shortly.
Make the Dialog Visible
// locate the dialog in the center of the
// editing pane and make it visible
dialog.pack();
dialog.setLocationRelativeTo(view);
dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
dialog.setVisible(true);
Here we do three things. First, we activate all the layout routines we have established by calling
the pack() method for the dialog as the top-level window. Next we center the dialog's position
in the active jEdit view by calling setLocationRelativeTo() on the dialog. We also
call the setDefaultCloseOperation() function to specify that the dialog box should be
immediately disposed if the user clicks the close box. Finally, we activate the dialog by calling
setVisible()with the state parameter set to true.
At this point we have a decent looking dialog window that doesn't do anything. Without more code,
it will not respond to user input and will not accomplish any text manipulation. The remainder of the
script deals with these two requirements.
The Action Listener
// this method will be called when a button is clicked
// or when ENTER is pressed
void actionPerformed(e)
{
if(e.getSource() != cancel)
{
processText();
}
dialog.dispose();
}
The method actionPerformed() nested inside prefixSuffixDialog() implements the
implicit ActionListener interface. It looks at the source of the ActionEvent, determined by
a call to getSource(). What we do with this return value is straightforward: if the source is not
the Cancel button, we call the processText() method to insert the prefix and suffix text. Then
the dialog is closed by calling its dispose() method.
The ability to implement interfaces like ActionListener inside a BeanShell script is one of the
more powerful features of the BeanShell package. this technique is discussed in the next chapter; see
the section called “Implementing Classes and Interfaces”.
Get the User's Input
// this is where the work gets done to insert
// the prefix and suffix
void processText()
{
prefix = prefixField.getText();
suffix = suffixField.getText();
if(prefix.length() == 0 && suffix.length() == 0)
return;
prefixField.addCurrentToHistory();
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A Dialog-Based Macro
suffixField.addCurrentToHistory();
The method processText() does the work of our macro. First we obtain the input from the
two text fields with a call to their getText() methods. If they are both empty, there is nothing
to do, so the method returns. If there is input, any text in the field is added to that field's stored
history list by calling addCurrentToHistory(). We do not need to test the prefixField or
suffixField controls for null or empty values because addCurrentToHistory() does
that internally.
Call jEdit Methods to Manipulate Text
// text manipulation begins here using calls
// to jEdit methods
buffer.beginCompoundEdit();
selectedLines = textArea.getSelectedLines();
for(i = 0; i < selectedLines.length; ++i)
{
offsetBOL = textArea.getLineStartOffset(
selectedLines[i]);
textArea.setCaretPosition(offsetBOL);
textArea.goToStartOfWhiteSpace(false);
textArea.goToEndOfWhiteSpace(true);
text = textArea.getSelectedText();
if(text == null) text = "";
textArea.setSelectedText(prefix + text + suffix);
}
buffer.endCompoundEdit();
}
The text manipulation routine loops through each selected line in the text buffer. We get the loop
parameters by calling textArea.getSelectedLines(), which returns an array consisting of
the line numbers of every selected line. The array includes the number of the current line, whether
or not it is selected, and the line numbers are sorted in increasing order. We iterate through each
member of the selectedLines array, which represents the number of a selected line, and apply
the following routine:
• Get the buffer position of the start of the line (expressed as a zero-based index from the start of
the buffer) by calling textArea.getLineStartOffset(selectedLines[i]);
• Move the caret to that position by calling textArea.setCaretPosition();
• Find the first and last non-whitespace characters on the line by
calling textArea.goToStartOfWhiteSpace() and
textArea.goToEndOfWhiteSpace();
The goTo... methods in JEditTextArea take a single parameter which tells jEdit whether the
text between the current caret position and the desired position should be selected. Here, we
call textArea.goToStartOfWhiteSpace(false) so that no text is selected, then call
textArea.goToEndOfWhiteSpace(true) so that all of the text between the beginning
and ending whitespace is selected.
• Retrieve the selected text by storing the return value of textArea.getSelectedText() in
a new variable text.
If the line is empty, getSelectedText() will return null. In that case, we assign an empty
string to text to avoid calling methods on a null object.
• Change the selected text to prefix + text + suffix by calling
textArea.setSelectedText(). If there is no selected text (for example, if the line is
empty), the prefix and suffix will be inserted without any intervening characters.
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A Dialog-Based Macro
Compound edits
Note the beginCompoundEdit() and endCompoundEdit() calls. These ensure
that all edits performed between the two calls can be undone in one step. Normally, jEdit
automatically wraps a macro call in these methods; however if the macro shows a non-modal
dialog box, as far as jEdit is concerned the macro has finished executing by the time the
dialog is shown, since control returns to the event dispatch thread.
If you do not understand this, don't worry; just keep it in mind if your macro needs to show a
non-modal dialog box for some reason; Most macros won't.
The Main Routine
// this single line of code is the script's main routine
prefixSuffixDialog();
The call to prefixSuffixDialog()is the only line in the macro that is not inside an enclosing
block. BeanShell treats such code as a top-level main method and begins execution with it.
Our analysis of Add_Prefix_and_Suffix.bsh is now complete. In the next section, we look
at other ways in which a macro can obtain user input, as well as other macro writing techniques.
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Chapter 15. Macro Tips and
Techniques
Getting Input for a Macro
The dialog-based macro discussed in Chapter 14, A Dialog-Based Macro reflects a conventional
approach to obtaining input in a Java program. Nevertheless, it can be too lengthy or tedious for
someone trying to write a macro quickly. Not every macro needs a user interface specified in such
detail; some macros require only a single keystroke or no input at all. In this section we outline
some other techniques for obtaining input that will help you write macros quickly.
Getting a Single Line of Text
As mentioned earlier in the section called “Helpful Methods in the Macros Class”, the method
Macros.input() offers a convenient way to obtain a single line of text input. Here is an
example that inserts a pair of HTML markup tags specified by the user.
// Insert_Tag.bsh
void insertTag()
{
caret = textArea.getCaretPosition();
tag = Macros.input(view, “Enter name of tag:”);
if( tag == null || tag.length() == 0) return;
text = textArea.getSelectedText();
if(text == null) text = “”;
sb = new StringBuffer();
sb.append(“<”).append(tag).append(“>”);
sb.append(text);
sb.append(“</”).append(tag).append(“>”);
textArea.setSelectedText(sb.toString());
if(text.length() == 0)
textArea.setCaretPosition(caret + tag.length() + 2);
}
insertTag();
// end Insert_Tag.bsh
Here the call to Macros.input() seeks the name of the markup tag. This method sets the
message box title to a fixed string, “Macro input”, but the specific message Enter name of tag
provides all the information necessary. The return value tag must be tested to see if it is null.
This would occur if the user presses the Cancel button or closes the dialog window displayed by
Macros.input().
Getting Multiple Data Items
If more than one item of input is needed, a succession of calls to Macros.input() is a
possible, but awkward approach, because it would not be possible to correct early input after the
corresponding message box is dismissed. Where more is required, but a full dialog layout is either
unnecessary or too much work, the Java method JOptionPane.showConfirmDialog() is
available. The version to use has the following prototype:
• public static int showConfirmDialog(Component parentComponent,
Object message, String title, int optionType, int messageType);
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Macro Tips and Techniques
The usefulness of this method arises from the fact that the message parameter can be an object of
any Java class (since all classes are derived from Object), or any array of objects. The following
example shows how this feature can be used.
// excerpt from Write_File_Header.bsh
title = “Write file header”;
currentName = buffer.getName();
nameField = new JTextField(currentName);
authorField = new JTextField(“Your name here”);
descField = new JTextField(“”, 25);
namePanel = new JPanel(new GridLayout(1, 2));
nameLabel = new JLabel(“Name of file:”, SwingConstants.LEFT);
saveField = new JCheckBox(“Save file when done”,
!buffer.isNewFile());
namePanel.add(nameLabel);
namePanel.add(saveField);
message = new Object[9];
message[0] = namePanel;
message[1] = nameField;
message[2] = Box.createVerticalStrut(10);
message[3] = “Author's name:”;
message[4] = authorField;
message[5] = Box.createVerticalStrut(10);
message[6] = “Enter description:”;
message[7] = descField;
message[8] = Box.createVerticalStrut(5);
if( JOptionPane.OK_OPTION !=
JOptionPane.showConfirmDialog(view, message, title,
JOptionPane.OK_CANCEL_OPTION,
JOptionPane.QUESTION_MESSAGE))
return null;
// *****remainder of macro script omitted*****
// end excerpt from Write_File_Header.bsh
This macro takes several items of user input and produces a formatted file header at the beginning of
the buffer. The full macro is included in the set of macros installed by jEdit. There are a number of
input features of this excerpt worth noting.
• The macro uses a total of seven visible components. Two of them are created behind the
scenes by showConfirmDialog(), the rest are made by the macro. To arrange them, the
script creates an array of Object objects and assigns components to each location in the
array. This translates to a fixed, top-to-bottom arrangement in the message box created by
showConfirmDialog().
• The macro uses JTextField objects to obtain most of the input data. The fields nameField
and authorField are created with constructors that take the initial, default text to be displayed
in the field as a parameter. When the message box is displayed, the default text will appear and
can be altered or deleted by the user.
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Macro Tips and Techniques
• The text field descField uses an empty string for its initial value. The second parameter in its
constructor sets the width of the text field component, expressed as the number of characters of
“average” width. When showConfirmDialog() prepares the layout of the message box, it
sets the width wide enough to accommodate the designated with of descField. This technique
produces a message box and input text fields that are wide enough for your data with one line of
code.
• The displayed message box includes a JCheckBox component that determines whether the
buffer will be saved to disk immediately after the file header is written. To conserve space in
the message box, we want to display the check box to the right of the label Name of file:. To do
that, we create a JPanel object and populate it with the label and the checkbox in a left-to-right
GridLayout. The JPanel containing the two components is then added to the beginning of
message array.
• The two visible components created by showConfirmDialog() appear at positions 3 and 6
of the message array. Only the text is required; they are rendered as text labels.
• There are three invisible components created by showConfirmDialog(). Each of them
involves a call to Box.createVerticalStrut(). The Box class is a sophisticated
layout class that gives the user great flexibility in sizing and positioning components.
Here we use a static method of the Box class that produces a vertical strut. This is a
transparent component whose width expands to fill its parent component (in this case, the
message box). The single parameter indicates the height of the strut in pixels. The last call to
createVerticalStrut() separates the description text field from the OK and Cancel
buttons that are automatically added by showConfirmDialog().
• Finally, the call to showConfirmDialog() uses defined constants for the option type and the
message type. The constants are the same as those used with the Macros.confirm() method;
see the section called “Helpful Methods in the Macros Class”. The option type signifies the use of
OK and Cancel buttons. The QUERY_MESSAGE message type causes the message box to display
a question mark icon.
The return value of the method is tested against the value OK_OPTION. If the return value is
something else (because the Cancel button was pressed or because the message box window was
closed without a button press), a null value is returned to a calling function, signaling that the
user canceled macro execution. If the return value is OK_OPTION, each of the input components
can yield their contents for further processing by calls to JTextField.getText() (or, in the
case of the check box, JCheckBox.isSelected()).
Selecting Input From a List
Another useful way to get user input for a macro is to use a combo box containing a number of preset options. If this is the only input required, one of the versions of showInputDialog() in the
JOptionPane class provides a shortcut. Here is its prototype:
• public static Object showInputDialog(Component parentComponent,
Object message, String title, int messageType, Icon icon,
Object[] selectionValues, Object initialSelectionValue);
This method creates a message box containing a drop-down list of the options
specified in the method's parameters, along with OK and Cancel buttons. Compared
to showConfirmDialog(), this method lacks an optionType parameter and has
three additional parameters: an icon to display in the dialog (which can be set to null),
an array of selectionValues objects, and a reference to one of the options as the
initialSelectionValue to be displayed. In addition, instead of returning an int
representing the user's action, showInputDialog() returns the Object corresponding to the
user's selection, or null if the selection is canceled.
The following macro fragment illustrates the use of this method.
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Macro Tips and Techniques
// fragment illustrating use of showInputDialog()
options = new Object[5];
options[0] = "JLabel";
options[1] = "JTextField";
options[2] = "JCheckBox";
options[3] = "HistoryTextField";
options[4} = "-- other --";
result = JOptionPane.showInputDialog(view,
"Choose component class",
"Select class for input component",
JOptionPane.QUESTION_MESSAGE,
null, options, options[0]);
The return value result will contain either the String object representing the selected text item
or null representing no selection. Any further use of this fragment would have to test the value of
result and likely exit from the macro if the value equaled null.
A set of options can be similarly placed in a JComboBox component created as part of a larger
dialog or showMessageDialog() layout. Here are some code fragments showing this approach:
// fragments from Display_Abbreviations.bsh
// import statements and other code omitted
// from main routine, this method call returns an array
// of Strings representing the names of abbreviation sets
abbrevSets = getActiveSets();
...
// from showAbbrevs() method
combo = new JComboBox(abbrevSets);
// set width to uniform size regardless of combobox contents
Dimension dim = combo.getPreferredSize();
dim.width = Math.max(dim.width, 120);
combo.setPreferredSize(dim);
combo.setSelectedItem(STARTING_SET); // defined as "global"
// end fragments
Using a Single Keypress as Input
Some macros may choose to emulate the style of character-based text editors such as emacs or
vi. They will require only a single keypress as input that would be handled by the macro but not
displayed on the screen. If the keypress corresponds to a character value, jEdit can pass that value as
a parameter to a BeanShell script.
The jEdit class InputHandler is an abstract class that that manages associations between keyboard
input and editing actions, along with the recording of macros. Keyboard input in jEdit is normally
managed by the derived class DefaultInputHandler. One of the methods in the InputHandler class
handles input from a single keypress:
• public void readNextChar(String prompt, String code);
When this method is called, the contents of the prompt parameter is shown in the view's status bar.
The method then waits for a key press, after which the contents of the code parameter will be run
as a BeanShell script, with one important modification. Each time the string __char__ appears in
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Macro Tips and Techniques
the parameter script, it will be substituted by the character pressed. The key press is “consumed” by
readNextChar(). It will not be displayed on the screen or otherwise processed by jEdit.
Using readNextChar() requires a macro within the macro, formatted as a single, potentially
lengthy string literal. The following macro illustrates this technique. It selects a line of text from the
current caret position to the first occurrence of the character next typed by the user. If the character
does not appear on the line, no new selection occurs and the display remains unchanged.
// Next_Char.bsh
script = new StringBuffer(512);
script.append( "start = textArea.getCaretPosition();"
script.append( "line = textArea.getCaretLine();"
script.append( "end = textArea.getLineEndOffset(line) + 1;"
script.append( "text = buffer.getText(start, end - start);"
script.append( "match = text.indexOf(__char__, 1);"
script.append( "if(match != -1) {"
script.append(
"if(__char__ != '\\n') ++match;"
script.append(
"textArea.select(start, start + match - 1);"
script.append( "}"
);
);
);
);
);
);
);
);
);
view.getInputHandler().readNextChar("Enter a character",
script.toString());
// end Next_Char.bsh
Once again, here are a few comments on the macro's design.
• A StringBuffer object is used for efficiency; it obviates multiple creation of fixed-length
String objects. The parameter to the constructor of script specifies the initial size of the
buffer that will receive the contents of the child script.
• Besides the quoting of the script code, the formatting of the macro is entirely optional but
(hopefully) makes it easier to read.
• It is important that the child script be self-contained. It does not run in the same namespace as the
“parent” macro Next_Char.bsh and therefore does not share variables, methods, or scripted
objects defined in the parent macro.
• Finally, access to the InputHandler object used by jEdit is available by calling
getInputHandler() on the current view.
Startup Scripts
On startup, jEdit runs any BeanShell scripts located in the startup subdirectory of the jEdit
installation and user settings directories (see the section called “The jEdit Settings Directory”). As
with macros, the scripts must have a .bsh file name extension. Startup scripts are run near the end
of the startup sequence, after plugins, properties and such have been initialized, but before the first
view is opened.
Startup scripts can perform initialization tasks that cannot be handled by command line options or
ordinary configuration options, such as customizing jEdit's user interface by changing entries in the
Java platform's UIManager class.
Startup scripts have an additional feature lacking in ordinary macros that can help you further
customize jEdit. Variables and methods defined in a startup script are available in all instances of
the BeanShell interpreter created in jEdit. This allows you to create a personal library of methods
and objects that can be accessed at any time during the editing session in another macro, the
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Macro Tips and Techniques
BeanShell shell of the Console plugin, or menu items such as Utilities>BeanShell>Evaluate
BeanShell Expression.
The startup script routine will run script files in the installation directory first, followed by scripts
in the user settings directory. In each case, scripts will be executed in alphabetical order, applied
without regard to whether the file name contains upper or lower case characters.
If a startup script throws an exception (because, for example, it attempts to call a method on a null
object). jEdit will show an error dialog box and move on to the next startup script. If script bugs are
causing jEdit to crash or hang on startup, you can use the -nostartupscripts command line
option to disable them for that editing session.
Another important difference between startup scripts and ordinary macros is that startup scripts
cannot use the pre-defined variables view, textArea, editPane and buffer. This is because
they are executed before the initial view is created.
If you are writing a method in a startup script and wish to use one of the above variables, pass
parameters of the appropriate type to the method, so that a macro calling them after startup can
supply the appropriate values. For example, a startup script could include a method
void doSomethingWithView(View v, String s)
...
}
{
so that during the editing session another macro can call the method using
doSomethingWithView(view, "something");
Reloading startup scripts without restarting
It is actually possible to reload startup scripts or load other scripts without restarting jEdit,
using a BeanShell statement like the following:
BeanShell.runScript(view,path,null,false);
For path, you can substitute any string, or a method call such as buffer.getPath().
Running Scripts from the Command Line
The -run command line switch specifies a BeanShell script to run on startup:
$ jedit -run=test.bsh
Note that just like with startup scripts, the view, textArea, editPane and buffer variables
are not defined.
If another instance is already running, the script will be run in that instance, and you will be able to
use the jEdit.getLastView() method to obtain a view. However, if a new instance of jEdit
is being started, the script will be run at the same time as all other startup scripts; that is, before the
first view is opened.
If your script needs a view instance to operate on, you can use the following code pattern to obtain
one, no matter how or when the script is being run:
void doSomethingUseful()
{
void run()
{
view = jEdit.getLastView();
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Macro Tips and Techniques
// put actual script body here
}
if(jEdit.getLastView() == null)
VFSManager.runInAWTThread(this);
else
run();
}
doSomethingUseful();
If the script is being run in a loaded instance, it can be invoked to perform its work immediately.
However, if the script is running at startup, before an initial view exists, its operation must be
delayed to allow the view object first to be created and displayed. In order to queue the macro's
operation, the scripted “closure” named doSomethingUseful() implements the Runnable
interface of the Java platform. That interface contains only a single run() method that takes no
parameters and has no return value. The macro's implementation of the run() method contains the
“working” portion of the macro. Then the scripted object, represented by a reference to this, is
passed to the runInAWTThread() method. This schedules the macro's operations for execution
after the startup routine is complete.
As this example illustrates, the runInAWTThread() method can be used to ensure that a macro
will perform operations after other operations have completed. If it is invoked during startup, it
schedules the specified Runnable object to run after startup is complete. If invoked when jEdit
is fully loaded, the Runnable object will execute after all pending input/output is complete, or
immediately if there are no pending I/O operations. This will delay operations on a new buffer, for
example, until after the buffer is loaded and displayed.
Advanced BeanShell Techniques
BeanShell has a few advanced features that we haven't mentioned yet. They will be discussed in this
section.
BeanShell's Convenience Syntax
We noted earlier that BeanShell syntax does not require that variables be declared or defined with
their type, and that variables that are not typed when first used can have values of differing types
assigned to them. In addition to this “loose” syntax, BeanShell allows a “convenience” syntax
for dealing with the properties of JavaBeans. They may be accessed or set as if they were data
members. They may also be accessed using the name of the property enclosed in quotation marks
and curly brackets. For example, the following statement are all equivalent, assuming btn is a
JButton instance:
b.setText("Choose");
b.text = "Choose";
b{"text"} = "Choose";
The last form can also be used to access a key-value pair of a Hashtable object.
Special BeanShell Keywords
BeanShell uses special keywords to refer to variables or methods defined in the current or an
enclosing block's scope:
• The keyword this refers to the current scope.
• The keyword super refers to the immediately enclosing scope.
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Macro Tips and Techniques
• The keyword global refers to the top-level scope of the macro script.
The following script illustrates the use of these keywords:
a = "top\n";
foo() {
a = "middle\n";
bar() {
a = "bottom\n";
textArea.setSelectedText(global.a);
textArea.setSelectedText(super.a);
// equivalent to textArea.setSelectedText(this.a):
textArea.setSelectedText(a);
}
bar();
}
foo();
When the script is run, the following text is inserted in the current buffer:
top
middle
bottom
Implementing Classes and Interfaces
As discussed in the macro example in Chapter 14, A Dialog-Based Macro, scripted objects can
implicitly implement Java interfaces such as ActionListener. For example:
myRunnable() {
run() {
System.out.println("Hello world!");
}
return this;
}
Runnable r = myRunnable();
new Thread(r).start();
Frequently it will not be necessary to implement all of the methods of a particular interface in order
to specify the behavior of a scripted object. To prevent BeanShell from throwing exceptions for
missing interface methods, implement the invoke() method, which is called when an undefined
method is invoked on a scripted object. Typically, the implementation of this method will do
nothing, as in the following example:
invoke(method, args) {}
In addition to the implicit interface definitions described above, BeanShell permits full-blown
classes to be defined. Indeed, almost any Java class definition should work in BeanShell:
class Cons {
// Long-live LISP!
Object car;
Object cdr;
rplaca(Object car) {
this.car = car;
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Macro Tips and Techniques
}
rplacd(Object cdr) {
this.cdr = cdr;
}
}
Debugging Macros
Here are a few techniques that can prove helpful in debugging macros.
Identifying Exceptions
An exception is a condition reflecting an error or other unusual result of program execution that
requires interruption of normal program flow and some kind of special handling. Java has a rich
(and extensible) collection of exception classes which represent such conditions.
jEdit catches exceptions thrown by BeanShell scripts and displays them in a dialog box. In
addition, the full traceback is written to the activity log (see Appendix B, The Activity Log for more
information about the activity log).
There are two broad categories of errors that will result in exceptions:
• Interpreter errors, which may arise from typing mistakes like mismatched brackets or missing
semicolons, or from BeanShell's failure to find a class corresponding to a particular variable.
Interpreter errors are usually accompanied by the line number in the script, along with the cause
of the error.
• Execution errors, which result from runtime exceptions thrown by the Java platform when macro
code is executed.
Some exceptions thrown by the Java platform can often seem cryptic. Nevertheless, examining
the contents of the activity log may reveals clues as to the cause of the error.
Using the Activity Log as a Tracing Tool
Sometimes exception tracebacks will say what kind of error occurred but not where it arose in the
script. In those cases, you can insert calls that log messages to the activity log in your macro. If the
logged messages appear when the macro is run, it means that up to that point the macro is fine; but
if an exception is logged first, it means the logging call is located after the cause of the error.
To write a message to the activity log, use the following method of the Log class:
• public static void log(int urgency, Object source, Object
message);
See the documentation for the Log class for information about the method's parameters.
The following code sends a typical debugging message to the activity log:
Log.log(Log.DEBUG, BeanShell.class, "counter = " + counter);
The corresponding activity log entry might read as follows:
[debug] BeanShell: counter = 15
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Macro Tips and Techniques
Using message dialog boxes as a tracing tool
If you would prefer not having to deal with the activity log, you can use the
Macros.message() method as a tracing tool. Just insert calls like the following in the
macro code:
Macros.message(view,"tracing");
Execution of the macro is halted until the message dialog box is closed. When you have
finished debugging the macro, you should delete or comment out the debugging calls to
Macros.message() in your final source code.
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Chapter 16. BeanShell Commands
BeanShell includes a set of commands; subroutines that can be called from any script or macro. The
following is a summary of those commands which may be useful within jEdit.
Note
Java classes in plugins cannot make use of BeanShell commands directly. However, these
commands can be called from BeanShell code that is part of a plugin, for example the
snippets in actions.xml, or any BeanShell scripts shipped with the plugin and loaded
on startup.
Output Commands
• void cat(String filename);
Writes the contents of filename to the activity log.
• void javap(String | Object | Class target);
Writes the public fields and methods of the specified class to the output stream of the current
process.
• void print(arg);
Writes the string value of the argument to the activity log, or if run from the Console plugin,
to the current output window. If arg is an array, print runs itself recursively on the array's
elements.
File Management Commands
• void cd(String dirname);
Changes the working directory of the BeanShell interpreter to dirname.
• void cp(String fromFile, String toFile);
Copy fromFile to toFile.
• void dir(String dirname);
Displays the contents of directory dirname. The format of the display is similar to the Unix ls
-l command.
• void mv(String fromFile, String toFile);
Moves the file named by fromFile to toFile.
• File pathToFile(String filename);
Create a File object corresponding to filename. Relative paths are resolved with reference to
the BeanShell interpreter's working directory.
• void pwd(void);
Writes the current working directory of the BeanShell interpreter to the output stream of the
current process.
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BeanShell Commands
• void rm(String pathname);
Deletes the file name by pathname.
Component Commands
• JFrame frame(Component frame);
Displays the component in a top-level JFrame, centered and packed. Returns the JFrame
object.
• Object load(String filename);
Loads and returns a serialized Java object from filename.
• void save(Component component, String filename);
Saves component in serialized form to filename.
• Font setFont(Component comp, int ptsize);
Set the font size of component to ptsize and returns the new font.
Resource Management Commands
• URL getResource(String path);
Returns the resource specified by path. An absolute path must be used to return any resource
available in the current classpath.
Script Execution Commands
• Thread bg(String filename);
Run the BeanShell script named by filename in a copy of the existing namespace and in a
separate thread. Returns the Thread object so created.
• void exec(String cmdline);
Start the external process by calling Runtime.exec() on cmdline. Any output is directed to
the output stream of the calling process.
• Object eval(String expression);
Evaluates the string expression as a BeanShell script in the interpreter's current namespace.
Returns the result of the evaluation of null.
• org.gjt.sp.jedit.bsh.This run(String filename);
Run the BeanShell script named by filename in a copy of the existing namespace. The return
value represent the object context of the script, allowing you to access its variables and methods.
• void setAccessibility(boolean flag);
If flag is true, BeanShell scripts are allowed to change and modify private variables, and call
private methods. The default is false.
• void setStrictJava(boolean flag);
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BeanShell Commands
If flag is true, BeanShell scripts must follow a much more strict, Java-like syntax, and are not
able to use the convenience features described in the section called “BeanShell's Convenience
Syntax”.
• void source(String filename);
Evaluates the contents of filename as a BeanShell script in the interpreter's current namespace.
BeanShell Object Management Commands
• bind(org.gjt.sp.jedit.bsh.This ths,
org.gjt.sp.jedit.bsh.Namespace namespace);
Binds the scripted object ths to namespace.
• void clear(void);
Clear all variables, methods, and imports from this namespace. If this namespace is the root, it
will be reset to the default imports.
• org.gjt.sp.jedit.bsh.This extend(org.gjt.sp.jedit.bsh.This
object);
Creates a new BeanShell This scripted object that is a child of the parameter object.
• void importObject(Object object);
Import an object into this namespace. This is somewhat similar to Java 1.5 static class imports,
except you can import the methods and fields of a Java object instance into a BeanShell
namespace, for example:
Map map = new HashMap();
importObject( map );
put("foo", "bar");
print( get("foo") ); // "bar"
• org.gjt.sp.jedit.bsh.This object(void);
Creates a new BeanShell This scripted object which can hold data members. You can use this to
create an object for storing miscellaneous crufties, like so:
crufties = object();
crufties.foo = "hello world";
crufties.counter = 5;
...
• setNameSpace(org.gjt.sp.jedit.bsh.Namespace namespace);
Set the namespace of the current scope to namespace.
• org.gjt.sp.jedit.bsh.This super(String scopename);
Returns a reference to the BeanShell This object representing the enclosing method scope
specified by scopename. This method work similar to the super keyword but can refer to
enclosing scope at higher levels in a hierarchy of scopes.
• void unset(String name);
Removes the variable named by name from the current interpreter namespace. This has the effect
of “undefining” the variable.
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BeanShell Commands
Other Commands
• void debug(void);
Toggles BeanShell's internal debug reporting to the output stream of the current process.
• getSourceFileInfo(void);
Returns the name of the file or other source from which the BeanShell interpreter is reading.
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Part IV. Writing Plugins
This part of the user's guide covers writing plugins for jEdit.
Like jEdit itself, plugins are written primarily in Java. While this guide assumes some working knowledge of
the language, you are not required to be a Java wizard. If you can write a useful application of any size in Java,
you can write a plugin.
Where applicable, this section will also explain how jEdit's source code is similar. Therefore, this is also a good
introduction to to jEdit development.
Chapter 17. Introducing the Plugin
API
The jEdit Plugin API provides a framework for hosting plugin applications without imposing any
requirements on the design or function of the plugin itself. You could write an application that
performs spell checking, displays a clock or plays chess and turn it into a jEdit plugin. There are
currently over 50 released plugins for jEdit. While none of them play chess, they perform a wide
variety of editing and file management tasks.
A detailed listing of available plugins is available at plugins.jedit.org. You can also find beta
versions of new plugins in the “Downloads” area of community.jedit.org.
Using the “Plugin Manager” feature of jEdit, users with an Internet connection can check for new
or updated plugins and install and remove them without leaving jEdit. See Chapter 9, Installing and
Using Plugins for details.
Requirements for “plugging in” to jEdit are as follows:
• This plugin must supply information about itself, such as its name, version, author, and
compatibility with versions of jEdit.
• The plugin must provide for activating, displaying and deactivating itself upon direction from
jEdit, typically in response to user input1. Make sure you can continue to use both your plugin
and the editor after it has been reloaded.
• Each Plugin has an ActionSet defined by jEdit, which is added to the main ActionContext. The
ActionSet is a container for EditAction instances. The plugin may define actions in a number of
ways. One way is explicitly, with an action definition file known as actions.xml. Another is
implicitly, by defining dockable windows in dockables.xml.
Most EditActions are small blocks of BeanShell code that jEdit will perform on behalf of
the plugin upon user request. They provide the “glue” between user input and specific plugin
routines.
By convention, plugins display their available actions in submenus of jEdit's Plugins menu; each
menu item corresponds to an action. Plugin authors do not define specific shortcuts - the user can/
will assign EditActions to keyboard shortcuts, toolbar buttons, or entries in the text area's Context
menu (right-click menu).
• The plugin may, but need not, provide a user interface.
If the plugin has a visible interface, it can be shown in any object derived from one of Java
top-level container classes: JWindow, JDialog, or JFrame. jEdit also provides a dockable
window API, which allows plugin windows derived from the JComponent class to be docked
into views or shown in top-level frames, at the user's request.
Plugins can also act directly upon jEdit's text area. They can add graphical elements to the text
display (like error highlighting in the case of the ErrorList plugin) or decorations surrounding
the text area (like the JDiff plugin's summary views). These plugins are dependent on the
JEditTextArea class, which is currently getting refactored.
• Plugins may provide a range of options that the user can modify to alter their configuration.
If a plugin provides configuration options in accordance with the plugin API, jEdit will make
them available in the Global Options dialog box.
1
You should test your plugin by loading and unloading it from both the Plugin Manager, as well as the Activator Plugin.
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Introducing the Plugin API
• While it is not required, plugins are encouraged to provide documentation.
As noted, many of these features are optional; it is possible to write a plugin that does not provide
actions, configuration options, or dockable windows. The majority of plugins, however, provide
most of these services.
Plugins and different jEdit versions
As jEdit continues to evolve and improve, elements of the API may change with a new jEdit
release.
On occasion an API change will break code used by plugins, although efforts are made
to maintain or deprecate plugin-related code on a transitional basis. While the majority
of plugins are unaffected by most changes and will continue working, it is a good idea to
monitor the jEdit change log, and join the jedit-devel mailing list, to keep updated on
changes and bug reports, so that you will know when your plugin needs to be updated. If you
allow the source code to be managed by the jEdit project, then other plugin developers can
help fix things when they break more easily.
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Chapter 18. Implementing a Simple
Plugin
There are many applications for the leading operating systems that provide a “scratch-pad” or
“sticky note” facility for the desktop display. A similar type of facility operating within the jEdit
display would be a convenience. The use of dockable windows would allow the notepad to be
displayed or hidden with a single mouse click or keypress (if a keyboard shortcut were defined). The
contents of the notepad could be saved at program exit (or, if earlier, deactivation of the plugin) and
retrieved at program startup or plugin activation.
We will keep the capabilities of this plugin modest, but a few other features would be worthwhile.
The user should be able to write the contents of the notepad to storage on demand. It should also
be possible to choose the name and location of the file that will be used to hold the notepad text.
This would allow the user to load other files into the notepad display. The path of the notepad file
should be displayed in the plugin window, but will give the user the option to hide the file name.
Finally, there should be an action by which a single click or keypress would cause the contents of
the notepad to be written to the new text buffer for further processing.
The full source code for QuickNotepad is contained in jEdit's source code distribution. We will
provide excerpts in this discussion where it is helpful to illustrate specific points. You are invited to
obtain the source code for further study or to use as a starting point for your own plugin.
How Plugins are Loaded
We will discuss the implementation of the QuickNotepad plugin, along with the jEdit APIs it makes
use of. But first, we describe how plugins are loaded.
As part of its startup routine, jEdit's main method calls various methods to load and initialize
plugins.
Additionally, plugins using the jEdit 4.2 plugin API can be loaded and unloaded at any time. This is
a great help when developing your own plugins -- there is no need to restart the editor after making
changes (see the section called “Reloading the Plugin” ).
Plugins are loaded from files with the .jar filename extension located in the jars subdirectories
of the jEdit installation and user settings directories (see the section called “The jEdit Settings
Directory”).
For each JAR archive file it finds, jEdit scans its entries and performs the following tasks:
• Adds to a collection maintained by jEdit a new object of type PluginJAR. This is a data
structure holding the name of the JAR archive file, a reference to the JARClassLoader, and a
collection of plugins found in the archive file.
• Loads any properties defined in files ending with the extension .props that are contained in the
archive. See the section called “The Property Files”.
• Reads action definitions from any file named actions.xml in the archive (the file need not be
at the top level). See the section called “The Actions.xml Catalog”.
• Parses and loads the contents of any file named dockables.xml in the archive (the file
need not be at the top level). This file contains BeanShell code for creating docking or floating
windows that will contain the visible components of the plugin. Not all plugins define dockable
windows, but those that do need a dockables.xml file. See the section called “The
dockables.xml Window Catalog”.
• Checks for a class name with a name ending with Plugin.class.
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Implementing a Simple Plugin
Such a class is known as a plugin core class and must extend jEdit's abstract EditPlugin
class.
The initialization routine checks the plugin's properties to see if it is subject to any dependencies.
For example, a plugin may require that the version of the Java runtime environment or of jEdit
itself be equal to or above some threshold version. A plugin can also require the presence of
another plugin.
If any dependency is not satisfied, the loader marks the plugin as “broken” and logs an error
message.
After scanning the plugin JAR file and loading any resources, a new instance of the plugin core
class is created and added to the collection maintained by the appropriate PluginJAR. jEdit
then calls the start() method of the plugin core class. The start() method can perform
initialization of the object's data members. Because this method is defined as an empty “no-op”
in the EditPlugin abstract class, a plugin need not provide an implementation if no unique
initialization is required.
The QuickNotepadPlugin Class
The major issues encountered when writing a plugin core class arise from the developer's decisions
on what features the plugin will make available. These issues have implications for other plugin
elements as well.
• Will the plugin provide for actions that the user can trigger using jEdit's menu items, toolbar
buttons and keyboard shortcuts?
• Will the plugin have its own visible interface?
• Will the plugin have settings that the user can configure?
• Will the plugin respond to any messages reflecting changes in the host application's state?
• Should the plugin do something special when it gets focus?
Recall that the plugin core class must extend EditPlugin. In QuickNotepad's plugin core class,
there are no special initialization or shutdown chores to perform, so we will not need a start() or
stop() method.
The resulting plugin core class is lightweight and straightforward to implement:
• public class QuickNotepadPlugin extends EditPlugin {
public static final String NAME = "quicknotepad";
public static final String OPTION_PREFIX = "options.quicknotepad.";
}
The class has been simplified since 4.1, and all we defined here were a couple of String data
members to enforce consistent syntax for the name of properties we will use throughout the
plugin.
• These names are used in actions.xml for each of the menu choices. This file is discussed in
more detail in the section called “The Actions.xml Catalog”. Each action is a beanshell script.
<!DOCTYPE ACTIONS SYSTEM "actions.dtd">
<ACTIONS>
<ACTION NAME="quicknotepad.choose-file">
<CODE>
wm.addDockableWindow(QuickNotepadPlugin.NAME);
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Implementing a Simple Plugin
wm.getDockableWindow(QuickNotepadPlugin.NAME).chooseFile();
</CODE>
</ACTION>
<ACTION NAME="quicknotepad.save-file">
<CODE>
wm.addDockableWindow(QuickNotepadPlugin.NAME);
wm.getDockableWindow(QuickNotepadPlugin.NAME).saveFile();
</CODE>
</ACTION>
<ACTION NAME="quicknotepad.copy-to-buffer">
<CODE>
wm.addDockableWindow(QuickNotepadPlugin.NAME);
wm.getDockableWindow(QuickNotepadPlugin.NAME).copyToBuffer();
</CODE>
</ACTION>
</ACTIONS>
• The names also come up in the properties file, QuickNotePad.props file. The properties
define option panes and strings used by the plugin. It is explained in more detail in the section
called “The Property Files” and the EditPlugin API docs.
# jEdit only needs to load the plugin the first time the user accesses it
# the presence of this property also tells jEdit the plugin is using the new A
plugin.QuickNotepadPlugin.activate=defer
# Even if you don't store additional files, this is a good idea to set:
plugin.QuickNotepadPlugin.usePluginHome=true
# Required for all plugins:
plugin.QuickNotepadPlugin.name=QuickNotepad
plugin.QuickNotepadPlugin.author=John Gellene
# version number == jEdit version number
plugin.QuickNotepadPlugin.version=4.5
# online help
plugin.QuickNotepadPlugin.docs=index.html
# we only have one dependency, jEdit 4.5
# See jEdit.getBuild() to understand version numbering scheme.
plugin.QuickNotepadPlugin.depend.0=jedit 4.05.99.00
# quicknotepad's plugin menu - a list of actions or separators
plugin.QuickNotepadPlugin.menu=quicknotepad \
- \
quicknotepad.choose-file \
quicknotepad.save-file \
quicknotepad.copy-to-buffer
# action labels for actions supplied by dockables.xml
quicknotepad.label=QuickNotepad
# action labels for actions supplied by actions.xml
quicknotepad.choose-file.label=Choose notepad file
quicknotepad.save-file.label=Save notepad file
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Implementing a Simple Plugin
quicknotepad.copy-to-buffer.label=Copy notepad to buffer
# plugin option pane
plugin.QuickNotepadPlugin.option-pane=quicknotepad
# Option pane activation BeanShell snippet
options.quicknotepad.code=new QuickNotepadOptionPane();
# Option pane labels
options.quicknotepad.label=QuickNotepad
options.quicknotepad.file=File:
options.quicknotepad.choose-file=Choose
options.quicknotepad.choose-file.title=Choose a notepad file
options.quicknotepad.choose-font=Font:
options.quicknotepad.show-filepath.title=Display notepad file path
# window title
quicknotepad.title=QuickNotepad
# window toolbar buttons
quicknotepad.choose-file.icon=Open.png
quicknotepad.save-file.icon=Save.png
quicknotepad.copy-to-buffer.icon=CopyToBuffer.png
# default settings
options.quicknotepad.show-filepath=true
options.quicknotepad.font=Monospaced
options.quicknotepad.fontstyle=0
options.quicknotepad.fontsize=14
# Setting not defined but supplied for completeness
options.quicknotepad.filepath=
The Property Files
jEdit maintains a list of “properties”, which are name/value pairs used to store human-readable
strings, user settings, and various other forms of meta-data. During startup, jEdit loads the default
set of properties, followed by plugin properties stored in plugin JAR files, finally followed by user
properties.
Some properties are used by the plugin API itself. Others are accessed by the plugin using methods
in the jEdit class. Others are accessed by the scripts used by plugin packagers 1.
Property files contained in plugin JARs must end with the filename extension .props, and have a
very simple syntax, which the following example illustrates:
# Lines starting with '#' are ignored.
name=value
another.name=another value
long.property=Long property value, split over \
several lines
escape.property=Newlines and tabs can be inserted \
using the \t and \n escapes
backslash.property=A backslash can be inserted by writing \\.
1
See the Macros/Properties/Create Plugin Announcement macro for an example.
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Implementing a Simple Plugin
Now we look at a fragment from the QuickNotepad.props file 2 which contains properties for
the QuickNotepad plugin. The first type of property data is information about the plugin itself; these
are the only properties that must be specified in order for the plugin to load:
# general plugin information
plugin.QuickNotepadPlugin.activate=defer
plugin.QuickNotepadPlugin.usePluginHome=true
plugin.QuickNotepadPlugin.name=QuickNotepad
plugin.QuickNotepadPlugin.author=John Gellene
plugin.QuickNotepadPlugin.version=4.5
plugin.QuickNotepadPlugin.docs=QuickNotepad.html
# depends on jEdit 4.5
plugin.QuickNotepadPlugin.depend.0=jedit 04.05.99.00
plugin.QuickNotepadPlugin.description=A demo jEdit plugin that provides a notepa
plugin.QuickNotepadPlugin.longdescription=description.html
These properties are each described in detail in the documentation for the EditPlugin class and
do not require further discussion here.
Next in the file comes a property that sets the title of the plugin's dockable window. Dockable
windows are discussed in detail in the section called “The dockables.xml Window Catalog”.
# dockable window name
quicknotepad.title=QuickNotepad
Next, we see menu item labels for the plugin's actions. All of these but the first are defined in
actions.xml file, and that is because the dockable itself has its own actions. Actions are
discussed further in the section called “The Actions.xml Catalog”.
# action labels
# Dockable label
quicknotepad.label=QuickNotepad
# Additional strings extracted from the plugin java source
quicknotepad.choose-file.label=Choose notepad file
quicknotepad.save-file.label=Save notepad file
quicknotepad.copy-to-buffer.label=Copy notepad to buffer
Next, the plugin's menu is defined. See the section called “The QuickNotepadPlugin Class”.
# application menu items
quicknotepad.menu.label=QuickNotepad
quicknotepad.menu=quicknotepad - quicknotepad.choose-file \
quicknotepad.save-file quicknotepad.copy-to-buffer
We have created a small toolbar as a component of QuickNotepad, so file names for the button icons
follow:
# plugin toolbar buttons
quicknotepad.choose-file.icon=Open.png
quicknotepad.save-file.icon=Save.png
quicknotepad.copy-to-buffer.icon=Edit.png
The menu item labels corresponding to these icons will also serve as tooltip text.
Finally, the properties file set forth the labels and settings used by the option pane:
# Option pane labels
options.quicknotepad.label=QuickNotepad
options.quicknotepad.file=File:
options.quicknotepad.choose-file=Choose
2
Examine the actual file for a more complete example
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Implementing a Simple Plugin
options.quicknotepad.choose-file.title=Choose a notepad file
options.quicknotepad.choose-font=Font:
options.quicknotepad.show-filepath.title=Display notepad file path
# Initial default font settings
options.quicknotepad.show-filepath=true
options.quicknotepad.font=Monospaced
options.quicknotepad.fontstyle=0
options.quicknotepad.fontsize=14
# Setting not defined but supplied for completeness
options.quicknotepad.filepath=
PropertySideKick
There is a SideKick for Property files, provided in the JavaSideKick plugin. This gives you
a compact and sorted tree view of property files.
Localization Files
In addition to property files ending in .props, you will find property files with the names like
lang_de.properties. Each of these files provides localized strings for a particular locale. In
the example above, it is for the German locale. These files are loaded by jEdit automatically when
that locale is in use. They need to have a different filename extension from the other property files
so they can be treated differently from the regular properties.
The EditBus
jEdit (and some plugins) generate several kinds of messages to alert plugins and other components
of jedit-specific events. The message classes, all derived from EBMessage cover the opening and
closing of the application, changes in the status of buffers and views, changes in user settings, as
well as changes in the state of other program features. A full list of messages can be found in the
org.gjt.sp.jedit.msg package.
For example, the ViewUpdate messages are all related to the jEdit View, or the top-level window. If
the user creates multiple Views, a plugin may need to know when they are created or destroyed, so it
would monitor ViewUpdate messages.
BufferUpdate messages are all related to jEdit buffers. They let plugins know when a buffer has
become dirty, when it is about to be closed, after it is closed, created, loaded, or saved. Each of these
messages are described in further detail in the API docs.
As another example, The Navigator plugin monitors an EBMessage of the kind BufferChanging.
The BufferChanging event provides Navigator enough advance notice to save the TextArea's caret
just before the current EditPane changes its active Buffer. The BufferChanged event, another
EditPaneUpdate message, is thrown shortly afterward. This is not used by Navigator, but it is
used by SideKick to determine when it is time to reparse the buffer.
Plugins register EBComponent instances with the EditBus to receive messages reflecting
changes in jEdit's state.
EBComponents are added and removed with the EditBus.addToBus() and
EditBus.removeFromBus() methods.
Typically, the EBComponent.handleMessage() method is implemented with one or more
if blocks that test whether the message is an instance of a derived message class in which the
component has an interest.
if(msg instanceof BufferUpdate) {
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Implementing a Simple Plugin
// a buffer's state has changed!
}
else if(msg instanceof ViewUpdate) {
// a view's state has changed!
}
// ... and so on
If a plugin core class will respond to EditBus messages, it can be derived from EBPlugin, in
which case no explicit addToBus() call is necessary. Otherwise, EditPlugin will suffice as a
plugin base class. Note that QuickNotepad uses the latter.
Using the Activity Log to see the EditBus
To determine precisely which EditBus messages are being sent by jEdit or the plugins,
start up jEdit with an additional argument, -log=5. You can set an even lower log level
to see further details (the default is 7). With a log level of 5 or lower, the Activity Log will
include [notice]s, which will show us exactly which EditBus message is sent and when. See
Appendix B, The Activity Log for more details.
The Actions.xml Catalog
In jEdit as well as in Plugins, actions define procedures that can be bound to a menu item, a toolbar
button or a keyboard shortcut. Most plugin Actions 3 are short scripts written in BeanShell, jEdit's
macro scripting language. These scripts either direct the action themselves, delegate to a method in
one of the plugin's classes that encapsulates the action, or do a little of both. The scripts are usually
short; elaborate action protocols are usually contained in compiled code, rather than an interpreted
macro script, to speed execution.
Actions are defined by creating an XML file entitled actions.xml and placing it in the plugin
JAR file.
The actions.xml file from the QuickNotepad plugin looks as follows:
<ACTIONS>
<ACTION NAME="quicknotepad.choose-file">
<CODE>
wm.addDockableWindow(QuickNotepadPlugin.NAME);
wm.getDockableWindow(QuickNotepadPlugin.NAME).chooseFile();
</CODE>
</ACTION>
<ACTION NAME="quicknotepad.save-file">
<CODE>
wm.addDockableWindow(QuickNotepadPlugin.NAME);
wm.getDockableWindow(QuickNotepadPlugin.NAME).saveFile();
</CODE>
</ACTION>
<ACTION NAME="quicknotepad.copy-to-buffer">
<CODE>
wm.addDockableWindow(QuickNotepadPlugin.NAME);
wm.getDockableWindow(QuickNotepadPlugin.NAME).copyToBuffer();
</CODE>
</ACTION>
</ACTIONS>
3
Some plugins, such as Sidekick, Console, and ProjectViewer, create pure Java EditAction-derived Actions, based which services are
available, or which files are found in a certain path. However, this is an advanced topic you can explore further in the source and API docs
of those plugins.
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Implementing a Simple Plugin
Actions in jEdit core
You can see how each action in jEdit core is implemented by inspecting the
actions.xml file that is there.
This file defines three actions. They each use a built-in variable wm, which refers to the current
view's DockableWindowManager. Whenever you need to obtain a reference to the current
dockable, or create a new one, this is the class to use. We use the method addDockable()
followed by getDockable() to create if necessary, and then bring up the QuickNotepad
plugin dockable. This will be docked or floating, depending on how it was last used.
When an action is invoked, the BeanShell scripts address the plugin through static methods, or
if instance data is needed, the current View, its DockableWindowManager, and the plugin
object return by the getDockable() method.
If you are unfamiliar with BeanShell code, you may nevertheless notice that the code statements
bear a strong resemblance to Java code, with one exception: the variable view is never assigned
any value.
For complete answers to this and other BeanShell mysteries, see Part III, “Writing Macros”; two
observations will suffice here. First, the variable view is predefined by jEdit's implementation of
BeanShell to refer to the current View object. Second, the BeanShell scripting language is based
upon Java syntax, but allows variables to be typed at run time, so explicit types for variables need
not be declared.
A formal description of each element of the actions.xml file can be found in the documentation
of the ActionSet class.
The dockables.xml Window Catalog
A Dockable is a window that can float like a dialog, or dock into jEdit's docking area. Each
dockable needs a label (for display in menus, and on small buttons) and a title (for display in the
floating window's title bar).
The jEdit API uses BeanShell to create the top-level visible container of a plugin's interface. The
BeanShell code is contained in a file named dockables.xml. It usually is quite short, providing
only a single BeanShell expression used to create a visible plugin window.
The following example from the QuickNotepad plugin illustrates the requirements of the data file:
<?xml version="1.0"?>
<!DOCTYPE DOCKABLES SYSTEM "dockables.dtd">
<DOCKABLES>
<DOCKABLE NAME="quicknotepad">
new QuickNotepad(view, position);
</DOCKABLE>
</DOCKABLES>
In this example, the <DOCKABLE> element has a single attribute, the dockable window's identifier.
This attribute is used to key a property where the window title is stored; see the section called “The
Property Files”.
For each dockable, jedit defines an action with the same name. This means you do not need to
define an explicit action to create your dockable - in fact, jEdit defines three actions: "toggle", "get"
and "new floating instance" for each.
The contents of the <DOCKABLE> element itself is a BeanShell expression that constructs a new
QuickNotepad object. The view and position are predefined by the plugin API as the
view in which the plugin window will reside, and the docking position of the plugin. You can use
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Implementing a Simple Plugin
position to customize the layout of your plugin depending on whether it appears on the sides, or
the top/bottom, or as a floating dockable.
A formal description of each element of the dockables.xml file can be found in the
documentation of the DockableWindowManager class. This class also contains the public
interface you should use for getting, showing, hiding, and other interactions with the plugin's toplevel windows.
jEdit's dockables
jEdit has its own dockables.xml file that you can inspect to see how jEdit creates its
own dockables.
The services.xml file
A "service" is a mechanism by which one plugin can work with other plugins and avoid a
bidirectional build-dependency. For example, the XML plugin "depends" on Sidekick, but in fact, it
is SideKick which creates and operates on an object (a SideKickParser, in fact) defined in the
XML plugin. In a way, the dependency is bidirectional.
Similarly, the SshConsole plugin defines but does not instantiate a Shell object. It is the Console
plugin which creates a specific shell for each available service. SideKick and Console use the
ServiceManager to search for services offered by other plugins.
Here is an example of a service from the XML plugin, which extends Sidekick:
<!DOCTYPE SERVICES SYSTEM "services.dtd">
<SERVICES>
<SERVICE CLASS="sidekick.SideKickParser" NAME="html">
new sidekick.html.HtmlParser();
</SERVICE>
[...]
</SERVICES>
The value of the CLASS= should be a base-class or interface of the object that is returned by
executing the beanshell factory method enclosed in the <SERVICE> tag.
In the case above, the returned object tells Sidekick how it can parse files of a specific type
(HTML). The API docs for SideKickParser should indicate precisely which methods must be
implemented in a plugin which offers this service.
For more information about services, refer to the ServiceManager class API documentation. There,
you can find out what the tags and attributes mean, as well as how to register and use services. You
can also inspect the services.xml file of jEdit core to see what services are offered by jEdit
itself.
The QuickNotepad Class
Here is where most of the features of the plugin will be implemented. To work with the dockable
window API, the top level window will be a JPanel. The visible components reflect a simple
layout. Inside the top-level panel we will place a scroll pane with a text area. Above the scroll
pane we will place a panel containing a small tool bar and a label displaying the path of the current
notepad file.
We have identified three user actions that need implementation here: chooseFile(),
saveFile(), and copyToBuffer(). As noted earlier, we also want the text area to change
its appearance in immediate response to a change in user options settings. In order to do that, the
window class must respond to a PropertiesChanged message from the EditBus.
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Implementing a Simple Plugin
Unlike the EBPlugin class, the EBComponent interface does not deal with the component's
actual subscribing and unsubscribing to the EditBus. To accomplish this, we use a pair of methods
inherited from the Java platform's JComponent class that are called when the window is made
visible, and when it is hidden. These two methods, addNotify() and removeNotify(), are
overridden to add and remove the visible window from the list of EditBus subscribers.
We will provide for two minor features when the notepad is displayed in the floating window. First,
when a floating plugin window is created, we will give the notepad text area input focus. Second,
when the notepad if floating and has input focus, we will have the Escape key dismiss the notepad
window. An AncestorListener and a KeyListener will implement these details.
Here is the listing for the data members, the constructor, and the implementation of the
EBComponent interface:
public class QuickNotepad extends JPanel
implements EBComponent
{
private String filename;
private String defaultFilename;
private View view;
private boolean floating;
private QuickNotepadTextArea textArea;
private QuickNotepadToolPanel toolPanel;
//
// Constructor
//
public QuickNotepad(View view, String position)
{
super(new BorderLayout());
this.view = view;
this.floating = position.equals(
DockableWindowManager.FLOATING);
this.filename = jEdit.getProperty(
QuickNotepadPlugin.OPTION_PREFIX
+ "filepath");
if(this.filename == null || this.filename.length() == 0)
{
this.filename = new String(jEdit.getSettingsDirectory()
+ File.separator + "qn.txt");
jEdit.setProperty(QuickNotepadPlugin.OPTION_PREFIX
+ "filepath",this.filename);
}
this.defaultFilename = new String(this.filename);
this.toolPanel = new QuickNotepadToolPanel(this);
add(BorderLayout.NORTH, this.toolPanel);
if(floating)
this.setPreferredSize(new Dimension(500, 250));
textArea = new QuickNotepadTextArea();
textArea.setFont(QuickNotepadOptionPane.makeFont());
textArea.addKeyListener(new KeyHandler());
textArea.addAncestorListener(new AncestorHandler());
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Implementing a Simple Plugin
JScrollPane pane = new JScrollPane(textArea);
add(BorderLayout.CENTER, pane);
readFile();
}
//
// Attribute methods
//
// for toolBar display
public String getFilename()
{
return filename;
}
//
// EBComponent implementation
//
public void handleMessage(EBMessage message)
{
if (message instanceof PropertiesChanged)
{
propertiesChanged();
}
}
private void propertiesChanged()
{
String propertyFilename = jEdit.getProperty(
QuickNotepadPlugin.OPTION_PREFIX + "filepath");
if(!defaultFilename.equals(propertyFilename))
{
saveFile();
toolPanel.propertiesChanged();
defaultFilename = propertyFilename.clone();
filename = defaultFilename.clone();
readFile();
}
Font newFont = QuickNotepadOptionPane.makeFont();
if(!newFont.equals(textArea.getFont()))
{
textArea.setFont(newFont);
textArea.invalidate();
}
}
// These JComponent methods provide the appropriate points
// to subscribe and unsubscribe this object to the EditBus
public void addNotify()
{
super.addNotify();
EditBus.addToBus(this);
}
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Implementing a Simple Plugin
public void removeNotify()
{
saveFile();
super.removeNotify();
EditBus.removeFromBus(this);
}
...
}
This listing refers to a QuickNotebookTextArea object. It is currently implemented as a
JTextArea with word wrap and tab sizes hard-coded. Placing the object in a separate class will
simply future modifications.
The QuickNotepadToolBar Class
There is nothing remarkable about the toolbar panel that is placed inside the QuickNotepad
object. The constructor shows the continued use of items from the plugin's properties file.
public class QuickNotepadToolPanel extends JPanel
{
private QuickNotepad pad;
private JLabel label;
public QuickNotepadToolPanel(QuickNotepad qnpad)
{
pad = qnpad;
JToolBar toolBar = new JToolBar();
toolBar.setFloatable(false);
toolBar.add(makeCustomButton("quicknotepad.choose-file",
new ActionListener() {
public void actionPerformed(ActionEvent evt) {
QuickNotepadToolPanel.this.pad.chooseFile();
}
}));
toolBar.add(makeCustomButton("quicknotepad.save-file",
new ActionListener() {
public void actionPerformed(ActionEvent evt) {
QuickNotepadToolPanel.this.pad.saveFile();
}
}));
toolBar.add(makeCustomButton("quicknotepad.copy-to-buffer",
new ActionListener() {
public void actionPerformed(ActionEvent evt) {
QuickNotepadToolPanel.this.pad.copyToBuffer();
}
}));
label = new JLabel(pad.getFilename(),
SwingConstants.RIGHT);
label.setForeground(Color.black);
label.setVisible(jEdit.getProperty(
QuickNotepadPlugin.OPTION_PREFIX
+ "show-filepath").equals("true"));
this.setLayout(new BorderLayout(10, 0));
this.add(BorderLayout.WEST, toolBar);
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Implementing a Simple Plugin
this.add(BorderLayout.CENTER, label);
this.setBorder(BorderFactory.createEmptyBorder(0, 0, 3, 10));
}
...
}
The method makeCustomButton() provides uniform attributes for the three toolbar buttons
corresponding to three of the plugin's use actions. The menu titles for the user actions serve double
duty as tooltip text for the buttons. There is also a propertiesChanged() method for the
toolbar that sets the text and visibility of the label containing the notepad file path.
The QuickNotepadOptionPane Class
Using the default implementation provided by AbstractOptionPane reduces the preparation
of an option pane to two principal tasks: writing a _init() method to layout and initialize the
pane, and writing a _save() method to commit any settings changed by user input. If a button on
the option pane should trigger another dialog, such as a JFileChooser or jEdit's own enhanced
VFSFileChooserDialog, the option pane will also have to implement the ActionListener
interface to display additional components.
The QuickNotepad plugin has only three options to set: the path name of the file that will store the
notepad text, the visibility of the path name on the tool bar, and the notepad's display font. Using the
shortcut methods of the plugin API, the implementation of _init() looks like this:
public class QuickNotepadOptionPane extends AbstractOptionPane
implements ActionListener
{
private JTextField pathName;
private JButton pickPath;
private FontSelector font;
...
public void _init()
{
showPath = new JCheckBox(jEdit.getProperty(
QuickNotepadPlugin.OPTION_PREFIX
+ "show-filepath.title"),
jEdit.getProperty(
QuickNotepadPlugin.OPTION_PREFIX + "show-filepath")
.equals("true"));
addComponent(showPath);
pathName = new JTextField(jEdit.getProperty(
QuickNotepadPlugin.OPTION_PREFIX
+ "filepath"));
JButton pickPath = new JButton(jEdit.getProperty(
QuickNotepadPlugin.OPTION_PREFIX
+ "choose-file"));
pickPath.addActionListener(this);
JPanel pathPanel = new JPanel(new BorderLayout(0, 0));
pathPanel.add(pathName, BorderLayout.CENTER);
pathPanel.add(pickPath, BorderLayout.EAST);
addComponent(jEdit.getProperty(
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Implementing a Simple Plugin
QuickNotepadPlugin.OPTION_PREFIX + "file"),
pathPanel);
font = new FontSelector(makeFont());
addComponent(jEdit.getProperty(
QuickNotepadPlugin.OPTION_PREFIX + "choose-font"),
font);
}
...
}
Here we adopt the vertical arrangement offered by use of the addComponent() method with one
embellishment. We want the first “row” of the option pane to contain a text field with the current
notepad file path and a button that will trigger a file chooser dialog when pressed. To place both of
them on the same line (along with an identifying label for the file option), we create a JPanel to
contain both components and pass the configured panel to addComponent().
The _init() method uses properties from the plugin's property file to provide the names of
label for the components placed in the option pane. It also uses a property whose name begins with
PROPERTY_PREFIX as a persistent data item - the path of the current notepad file. The elements
of the notepad's font are also extracted from properties using a static method of the option pane
class.
The _save() method extracts data from the user input components and assigns them to the
plugin's properties. The implementation is straightforward:
public void _save()
{
jEdit.setProperty(QuickNotepadPlugin.OPTION_PREFIX
+ "filepath", pathName.getText());
Font _font = font.getFont();
jEdit.setProperty(QuickNotepadPlugin.OPTION_PREFIX
+ "font", _font.getFamily());
jEdit.setProperty(QuickNotepadPlugin.OPTION_PREFIX
+ "fontsize", String.valueOf(_font.getSize()));
jEdit.setProperty(QuickNotepadPlugin.OPTION_PREFIX
+ "fontstyle", String.valueOf(_font.getStyle()));
jEdit.setProperty(QuickNotepadPlugin.OPTION_PREFIX
+ "show-filepath", String.valueOf(showPath.isSelected()));
}
The class has only two other methods, one to display a file chooser dialog in response to user action,
and the other to construct a Font object from the plugin's font properties. They do not require
discussion here.
Plugin Documentation
While not required by the plugin API, a help file is an essential element of any plugin written for
public release. A single web page is often all that is required. There are no specific requirements on
layout, but because of the design of jEdit's help viewer, the use of frames should be avoided. Topics
that would be useful include the following:
• a description of the purpose of the plugin;
• an explanation of the type of input the user can supply through its visible interface (such as mouse
action or text entry in controls);
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Implementing a Simple Plugin
• a listing of available user actions that can be taken when the plugin does not have input focus;
• a summary of configuration options;
• information on development of the plugin (such as a change log, a list of “to do” items, and
contact information for the plugin's author); and
• licensing information, including acknowledgments for any library software used by the plugin.
The location of the plugin's help file is stored in the plugin.QuickNotepad.docs property;
see the section called “The Property Files”.
The build.xml Ant build file
We have already outlined the contents of the user action catalog, the properties file and the
documentation file in our earlier discussion. The final step is to compile the source file and build the
archive file that will hold the class files and the plugin's other resources.
Publicly released plugins include with their source a makefile in XML format for the Ant
utility. The format for this file requires few changes from plugin to plugin. Here is a version of
build.xml that could be used by QuickNotepad:
<project name="QuickNotepad" default="build">
<description>
This is an ant build.xml file for building the QuickNotepad plugin for jEdit
</description>
<property file="build.properties"/>
<property file="../build.properties"/>
<property name="user-doc.xml" location = "users-guide.xml"/>
<import file="${build.support}/plugin-build.xml" />
<!-- Extra files that should be included in the jar -->
<selector id="packageFiles">
<or>
<filename name="*.txt" />
</or>
</selector>
</project>
This build file imports another modular build file, plugin-build.xml from the buildsupport project. It is available as a package you can check out from subversion, or found online
in the jEdit's SVN repository. It contains the common build steps used to build the core jEdit
plugins, and some example build.properties.sample files which you can adapt for use
with your development environment.
Customizing this build file for a different plugin will likely only require three changes to build.xml
file:
• the name of the project
• the dependencies of the plugin
• The extra files that need to be copied into the jar.
Because this build file and those used by most plugins import a build.properties file from
the current and the parent directories, it is possible to build most of jEdit's plugins in a uniform
way by setting the common properties in a single build.properties file, placed in the plugin
source's parent directory.
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Implementing a Simple Plugin
Tip
For a full discussion of the Ant file format and command syntax, you should consult the
Ant documentation, also available through jEdit's help system if you installed the Ant
Plugin. When editing Ant build files, the XML plugin gives you completion tips for both
elements and attributes. The Console plugin provides you with an ANT button which you
can bind to keyboard actions. In addition, there are the AntFarm and Antelope plugins
which also proivde you with alternate means to execute Ant targets through the Console.
Reloading the Plugin
Once you have compiled your plugin, you will need to test its behavior when it is reloaded. Follow
these steps to reload your plugin without restarting jEdit:
• From the Plugins menu open the Plugin Manager.
• On the Manage tab uncheck Hide libraries. This will allow you to see plugins that are not loaded.
• Recheck the plugin to reload it.
Tip
The Activator plugin provides a very convenient (dockable) way to test the activating and
reloading behavior of your plugin. Be sure to test your plugin's reloading behavior with
both the Activator and the Reloader tabs.
If you have reached this point in the text, you are probably serious about writing a plugin for jEdit.
Good luck with your efforts, and thank you for contributing to the jEdit project.
Tips for debugging plugins
BeanShell
jEdit includes a Beanshell interface into its currently running JVM at all times. You can access it
a variety of ways, but one way is from Plugins - Console - Shells - BeanShell.
From here, you can interactively inspect the values of any object in memory, call any of its member
functions, or create new instances of any class that is currently loaded by jEdit or any of its plugins.
All this, without setting any breakpoints!
If you're too lazy to type each Beanshell statement interactively, you can also create debugging
code snippets as macros and invoke them from utilities - beanshell - evaluate
selection, or Macros - Misc - Evaluate Buffer in Beanshell, or place the file
in your own macros directory and bind it to its own keyboard shortcut.
Other useful tips
This section is new but will be expanded shortly. Please post suggestions to the jedit-devel
mailing list.
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Chapter 19. Plugin Tips and
Techniques
Utility Classes
If you need to check what the current running platform is, see
org.gjt.sp.jedit.OperatingSystem.
If you need to compare file names and don't want to worry about whether you are on a casesensitive file system or not, use MiscUtilities.pathsEqual(). See that class for other
useful path manipulation routines.
There are other helpful classes in org.gjt.sp.util, such as HtmlUtilities,
StandardUtilities, IOUtilities, and Log. In particular, the Log class is recommended
for reporting errors and also logging debug information.
If your plugin needs to "find a word" (using word boundaries) somewhere in the buffer, you might
want to reuse the org.gjt.sp.jedit.TextUtilities class.
Bundling Additional Class Libraries
Recall that any class whose name ends with Plugin.class is called a plugin core class. JAR
files with no plugin core classes are also loaded by jEdit; the classes they contain are made available
to other plugins. Many plugins that rely on third-party class libraries ship them as separate JAR
files. The libraries will be available inside the jEdit environment but are not part of a general
classpath or library collection when running other Java applications.
A plugin that bundles extra JAR files must list them in the plugin.class name.jars
property. See the documentation for the EditPlugin class for details.
Bundling Additional Non-Java Libraries
If your plugin bundles non-Java files, like native libraries, you need to list them in the
plugin.class name.files property. If you don't do so, they don't get deleted if the plugin is
uninstalled. See the documentation for the EditPlugin class for details.
Storing plugin data
If your plugin needs to create files and store data in the filesystem, you should use the
getPluginHome() API of the EditPlugin class. To signal that you use the plugin home API
you have to set the plugin.class name.usePluginHome property to true. Even if your
plugin doesn't create any files, you should set the property to true, so that e. g. the plugin manager
knows that there is actually no data in favor of not knowing if there is any data and thus displaying
that it doesn't know the data size. See the documentation for the EditPlugin class for details.
Plugin colors
There are a number of colors used by the View that should also be used by plugins where possible.
This helps promote a consistent color scheme throughout jEdit.
The main color properties are:
• view.bgColor - the background color of the main text area
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Plugin Tips and Techniques
• view.fgColor - the base foreground color for text in the main text area
• view.lineHighlightColor - color of the current line highlight
• view.selectionColor - the color of selected text in the main text area
• view.caretColor - the color of the caret in the main text area
• view.eolMarkerColor - the color of the end-of-line marker
To use these colors in your plugin, use
jEdit.getColorProperty("view.whatever", default_color)
For example, the QuickNotepad example should have lines like this:
textarea.setBackground(jEdit.getColorProperty("view.bgColor", Color.WHIT
textarea.setForeground(jEdit.getColorProperty("view.fgColor", Color.BLAC
This sets the foreground and background colors of QuickNotepad to be the same as those in the
View.
There are other color properties that may be useful, depending on what your plugin displays.
Gutter colors:
• view.gutter.bgColor
• view.gutter.currentLineColor
• view.gutter.fgColor
• view.gutter.focusBorderColor
• view.gutter.foldColor
• view.gutter.highlightColor
• view.gutter.markerColor
• view.gutter.noFocusBorderColor
• view.gutter.registerColor
• view.gutter.structureHighlightColor
Status bar colors:
• view.status.background
• view.status.foreground
• view.status.memory.background
• view.status.memory.foreground
Structure highlight colors:
• view.structureHighlightColor
• view.structureHighlightColor
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Plugin Tips and Techniques
Style colors. Use GUIUtilities.parseStyle for these.
• view.style.comment1
• view.style.comment2
• view.style.comment3
• view.style.comment4
• view.style.digit
• view.style.foldLine.0
• view.style.foldLine.1
• view.style.foldLine.2
• view.style.foldLine.3
• view.style.function
• view.style.invalid
• view.style.keyword1
• view.style.keyword2
• view.style.keyword3
• view.style.keyword4
• view.style.label
• view.style.literal1
• view.style.literal2
• view.style.literal3
• view.style.literal4
• view.style.markup
• view.style.operator
• view.wrapGuideColor
For example, here is a setting for a fold line color:
view.style.foldLine.0=color\:\#000000 bgColor\:\#f5deb8 style\:b
Passing the value to GUIUtilities.parseStyle will return a SyntaxStyle object, which you
can query for background color, foreground color, and font.
141
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