Red Hat | NETSCAPE ENTERPRISE SERVER 6.0 - NSAPI PROGRAMMER GUIDE | iPlanet Web Server 6.0, Enterprise Edition Programmer`s Guide to

Programmer’s Guide to Servlets
iPlanet Web Server, Enterprise Edition
Version 6.0
816-1381-01
May 2001
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CETTE DOCUMENTATION EST FOURNIE “EN L'ÉTAT”, ET TOUTES CONDITIONS EXPRESSES
OU IMPLICITES, TOUTES REPRÉSENTATIONS ET TOUTES GARANTIES, Y COMPRIS TOUTE
Contents
About This Book . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Chapter 1 Servlets and JavaServer Pages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Web Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Servlets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
JavaServer Pages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Chapter 2 Web Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Web Application Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Dynamic Reconfiguration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
web.xml Clarifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
login-config . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
security-constraint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
session-timeout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
The web-apps.xml File and Virtual Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
The Default Context for a Virtual Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Example server.xml File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Example web-apps.xml File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
web-apps.xml Element Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
auth-native . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
class-loader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
filter, filter-mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
form-login-session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
init-param . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
jsp-servlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
param-name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
param-value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
parameter-encoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
response-buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
3
4
response-cookie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
role-mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
session-cookie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
session-manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
session-tracking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
tempdir . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
vs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
web-app . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Deploying a Web Application using wdeploy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Web Application Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
24
24
25
25
25
26
26
26
27
29
Chapter 3 Using Servlets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
What Does the Server Need to Run Servlets? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using the User Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Enabling Servlets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Making Servlets Available to Clients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The <SERVLET> SHTML Tag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Servlet Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Configuring JVM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maximizing Servlet Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31
31
32
32
32
33
34
35
35
Chapter 4 Using JavaServer Pages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
What Does the Server Need to Run JSP? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Configuring JRE/JDK Paths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using the User Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Enabling JSPs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Making JSPs Available to Clients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Deleting Cache Version Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The JSP Command-Line Compiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Package Names Generated by the JSP Compiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Specifying that JSPs Are Precompiled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Other JSP Initialization Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
JSP Tag Libraries and Standard Portable Tags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
37
37
39
41
42
42
42
43
46
46
47
47
Chapter 5 Debugging Servlets and JSPs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Servlet Debugging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
JSP Debugging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Generating a Stack Trace for Debugging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using Forte for Java to Debug Servlets and JSPs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
JPDA Options for Debugging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
49
49
50
51
51
53
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Chapter 6 Session Managers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Session Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Specifying a Session Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
IWSSessionManager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Parameters for IWSSessionManager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Enabling IWSSessionManager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Source Code for IWSSessionManager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
MMapSessionManager (Unix Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Enabling MMapSessionManager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Deleting SessionData Version Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Deprecated Session Managers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
SimpleSessionManager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
JdbcSessionManager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Load Balancing, Session Failover, and Session IDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Chapter 7 API Clarifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Clarification of HttpSession Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Clarifications for Using Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
HttpServlet.service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
ServletContext.getAttribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
ServletRequest.setAttribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
ServletRequest.getParameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
ServletResponse.getOutputStream and getWriter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
RequestDispatcher.forward and include . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Other Useful Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Database Connection Pooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Fetching the Client Certificate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Chapter 8 Legacy Servlet and JSP Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The Default Virtual Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Enabling Servlets and JSP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Making JSPs Available to Clients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Configuring Servlets in the Default Virtual Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Configuring Global Servlet Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Registering Servlet Directories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Registering Individual Servlets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Specifying Servlet Virtual Paths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Specifying Servlet Contexts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using the User Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Legacy Configuration Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
servlets.properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
rules.properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contents
79
79
80
80
80
81
81
83
84
86
86
87
87
88
5
contexts.properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Legacy Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Maximizing Legacy Servlet Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Appendix A Servlet Settings in magnus.conf and obj.conf . . . . . . . . . . . . . . . . . . . . . . . . . .
Init Directives in magnus.conf . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Objects in obj.conf . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Directives for Registered Servlet Directories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
JSP Directives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
95
95
96
98
98
Appendix B Converting SSJS Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Differences Between JavaScript and Java . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
JavaScript to Java Class Conversions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Conversion Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Example Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Appendix C JVM Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The jvm12.conf File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using JVM Environment Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
jvm12.conf Parameter Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
105
105
106
107
Appendix D Remote Servlet Profiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
The Optimizeit! Profiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
The HPROF Profiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
6
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
About This Book
This book discusses how to enable and install Java servlets and JavaServer Pages
(JSP) in iPlanet™ Web Server, Enterprise Edition 6.0.
This book has the following chapters and appendices:
•
Chapter 1, “Servlets and JavaServer Pages”
This chapter introduces web applications, servlets, and JavaServer Pages.
•
Chapter 2, “Web Applications”
This chapter discusses the structure of web applications and how to deploy
them in iPlanet Web Server 6.0. It also lists example web applications and
describes the web-apps.xml file, which configures web applications for virtual
servers in iPlanet Web Server 6.0.
•
Chapter 3, “Using Servlets”
This chapter discusses how to enable and install servlets in iPlanet Web Server
6.0.
•
Chapter 4, “Using JavaServer Pages”
This chapter discusses how to enable and install JavaServer Pages in iPlanet
Web Server 6.0, including how to install the JDK.
•
Chapter 5, “Debugging Servlets and JSPs”
This chapter discusses how to debug servlets and JSPs, and includes a section
on debugging using Forte for Java.
•
Chapter 6, “Session Managers”
This chapter discusses the session managers provided with iPlanet Web Server
and explains how to customize session behavior to suit your own needs.
•
Chapter 7, “API Clarifications”
7
This chapter discusses methods in the Servlets API that behave marginally
differently in iPlanet Web Server than specified in the Sun Microsystems’
Servlets API documentation or where the behavior documented by Sun
Microsystems is ambiguous.
•
Chapter 8, “Legacy Servlet and JSP Configuration”
This chapter discusses how to configure the default virtual server as in iPlanet
Web Server 4.x, and the servlets.properties, rules.properties, and
contexts.properties files.
•
Appendix A, “Servlet Settings in magnus.conf and obj.conf”
This appendix discusses how the configuration file obj.conf changes
depending on the settings for servlets and JSP.
•
Appendix B, “Converting SSJS Applications”
This appendix discusses how to convert LiveWire applications to JSPs.
•
Appendix C, “JVM Configuration”
This appendix discusses how to manually specify JVM configuration
information.
•
Appendix D, “Remote Servlet Profiling”
This appendix discusses how to enable remote profiling for servlets.
NOTE
8
Throughout this manual, all Unix-specific descriptions apply to the
Linux operating system as well, except where Linux is specifically
mentioned.
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Chapter
1
Servlets and JavaServer Pages
iPlanet Web Server 6.0 supports servlets and JavaServer Pages (JSPs). This chapter
gives a brief overview of servlets and JSPs in iPlanet Web Server 6.0.
The sections in this chapter are:
•
Web Applications
•
Servlets
•
JavaServer Pages
iPlanet Web Server 6.0 runs with a specific version of the JRE or JDK that is
operating-system dependent. For more information, see “What Does the Server
Need to Run JSP?,” on page 37.
Web Applications
iPlanet Web Server 6.0 supports the Servlet 2.2 API specification, which allows
servlets and JSPs to be included in web applications.
A web application is a collection of servlets, JavaServer Pages, HTML documents,
and other web resources which might include image files, compressed archives,
and other data. A web application may be packaged into an archive (a WAR file) or
exist in an open directory structure.
For more details about web application support in iPlanet Web Server, see Chapter
2, “Web Applications.”
Although using web applications is recommended, you can still configure servlets
and JSPs as in iPlanet Web Server 4.x. For more information, see Chapter 8,
“Legacy Servlet and JSP Configuration.”
9
Servlets
Servlets
Java servlets are server-side Java programs that web servers can run to generate
content in response to a client request in much the same way as CGI programs do.
Servlets can be thought of as applets that run on the server side without a user
interface. Servlets are invoked through URL invocation.
iPlanet Web Server 6.0 supports the Java Servlet Specification version 2.2
(including Web Application and WAR file support).
NOTE
Servlet API version 2.2 is fully backward compatible with version
2.1, so all existing servlets will continue to work without
modification or recompilation.
To develop servlets, use Sun Microsystems’ Java Servlet API. For information
about using the Java Servlet API, see the documentation provided by Sun
Microsystems at:
http://java.sun.com/products/servlet/index.html
JavaServer Pages
iPlanet Web Server 6.0 supports JavaServer Pages (JSP) Specification version 1.1.
A JSP is a page, much like an HTML page, that can be viewed in a web browser.
However, in addition to HTML tags, it can include a set of JSP tags and directives
intermixed with Java code that extend the ability of the web page designer to
incorporate dynamic content in a page. These additional features provide
functionality such as displaying property values and using simple conditionals.
One of the main benefits of JSPs is that, like HTML pages, they do not need to be
compiled. The web page designer simply writes a page that uses HTML and JSP
tags and puts it on their web server. The web page designer does not need to learn
how to define Java classes or use Java compilers.
iPlanet Web Server supports precompilation of JSPs, however, and this is
recommended for production servers.
JSP pages can access full Java functionality in the following ways:
10
•
by embedding Java code directly in scriptlets in the page
•
by accessing Java beans
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
JavaServer Pages
•
by using server-side tags that include Java servlets
Both beans and servlets are Java classes that need to be compiled, but they can be
defined and compiled by a Java programmer, who then publishes the interface to
the bean or the servlet. The web page designer can access a pre-compiled bean or
servlet from a JSP page.
iPlanet Web Server 6.0 supports JSP tag libraries and standard portable tags.
For information about creating JSPs, see Sun Microsystem’s JavaServer Pages web
site at:
http://java.sun.com/products/jsp/index.html
For information about Java Beans, see Sun Microsystem’s JavaBeans web page at:
http://java.sun.com/beans/index.html
Chapter 1
Servlets and JavaServer Pages
11
JavaServer Pages
12
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Chapter
2
Web Applications
iPlanet Web Server 6.0 supports the Servlet 2.2 API specification, which allows
servlets and JSPs to be included in web applications.
A web application is a collection of servlets, JavaServer Pages, HTML documents,
and other web resources which might include image files, compressed archives,
and other data. A web application may be packaged into an archive (a WAR file) or
exist in an open directory structure. For more information about web applications, see the
Servlet 2.2 API specification:
http://java.sun.com/products/servlet/index.html
This chapter describes how web applications are supported in iPlanet Web Server,
and includes the following sections:
•
Web Application Structure
•
Dynamic Reconfiguration
•
web.xml Clarifications
•
The web-apps.xml File and Virtual Servers
•
Deploying a Web Application using wdeploy
•
Web Application Examples
Web Application Structure
Web Applications have a directory structure, all accessible from a mapping to the
application’s document root (for example, /catalog). The document root contains
JSP files, HTML files, and static files such as image files.
13
Dynamic Reconfiguration
A special directory under the document root, WEB-INF, contains everything related
to the application that is not in the public document tree of the application. No file
contained in WEB-INF can be served directly to the client. The contents of WEB-INF
include:
•
/WEB-INF/web.xml, an XML-based deployment descriptor that specifies the
web application configuration, including mappings, initialization parameters,
and security constraints.
•
/WEB-INF/classes/*, the directory for the servlet and utility classes.
•
/WEB-INF/lib/*.jar, the directory for the JAR files containing servlets, beans,
and other utility classes.
A WAR (web application archive) file contains a complete web application in
compressed form. iPlanet Web Server cannot access an application in a WAR file.
You must uncompress a web application (deploy it using the wdeploy utility)
before iPlanet Web Server can serve it.
Web application configuration includes two parts:
•
The web.xml file, which is the standard Servlets 2.2 deployment descriptor.
Each web application has its own web.xml file. For information about web.xml,
see the Servlet 2.2 API specification:
http://java.sun.com/products/servlet/index.html
•
The web-apps.xml file, which is specific to iPlanet Web Server. Each virtual
server has its own web-apps.xml file, which configures all the applications
running in that virtual server.
Dynamic Reconfiguration
When you make changes to a web application, you do not need to restart the
server. Changes are reloaded automatically at a frequency set in the
reload-interval attribute of the class-loader element in the web-apps.xml
file.
When you make changes to the web-xml or web-apps.xml file, you also do not
need to restart the server. However, you must apply the changes by clicking the
Apply link and then clicking the Load Configuration Files button on the Apply
Changes screen.
For more information about dynamic reconfiguration, see Chapter 1, “Basics of
Server Operation” in the NSAPI Programmer’s Guide for iPlanet Web Server.
14
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
web.xml Clarifications
If you add or remove a web application, servlet, or JSP, you must restart the server.
web.xml Clarifications
This section provides clarifications for using the web.xml file with iPlanet Web
Server 6.0.
login-config
If there is a security constraint and no login-config element is present, or if no
auth-method is specified, the auth-method defaults to BASIC. For BASIC
authentication, if no realm-name is specified, the realm-name defaults to iWS Web
Container. If auth-method is not FORM, the form-login-config element is
ignored even if specified.
security-constraint
if no url-pattern is specified, no constraints are applied. If no http-method is
specified in a web-resource-collection subelement, the constraint is applied to
all HTTP methods. If no transport-guarantee is specified in a
user-data-constraint subelement, it defaults to NONE. If no auth-constraint
subelement is present or if no role-name is specified, no user is allowed any access.
session-timeout
If session-timeout is specified in web.xml, this timeout value overrides any
timeOut parameter value specified in the session-manager element in
web-apps.xml. This override does not apply when you configure a single session
manager that all web applications in a virtual server use. It only applies when you:
•
Do not configure a session manager for all web applications in a virtual server
(the default behavior) Each web application has its own session manager.
•
Configure a web-application-specific session manager in addition to the
virtual-server-wide one. In that case, only the web-application-specific session
manager’s timeOut value is overridden.
Note that session-timeout value is specified in minutes while session-manager
timeOut parameters are specified in seconds.
For more information about session managers, see Chapter 6, “Session Managers.”
Chapter 2
Web Applications
15
The web-apps.xml File and Virtual Servers
The web-apps.xml File and Virtual Servers
The web-apps.xml file defines contexts for a set of web applications running in a
virtual server. The context information includes a context path of the web
application and other properties such as how it handles session management or
authentication.
The web-apps.xml file follows the standard J2EE deployment descriptor format: a
well-formed .XML document specified by a .dtd file. The web-apps.xml file
contains a set of web applications defined by their context path and physical
location.
Each web application may also define a number of configuration elements specific
to iPlanet Web Server that customize how the application is serviced. For example,
a web application can define pluggable session management or specify a java
compiler. The web-apps.xml file allows users to define a set of global
configuration elements and share (or override) them across multiple web
applications.
Each web-apps.xml file must be referenced in the server.xml file, which defines
virtual servers. For more information about server.xml, see the NSAPI
Programmer’s Guide for iPlanet Web Server.
The Default Context for a Virtual Server
When you create a new virtual server, an empty web-apps.xml file is created. You
can use the default context that is created automatically, or you can create your
own by modifying the web-apps.xml file.
If a servlets.properties file is present in the default virtual server (in the
config directory of the server instance), an iPlanet Web Server 4.x servlet context is
created instead of a web application context. For more information about legacy
configuration, see Chapter 8, “Legacy Servlet and JSP Configuration.”
Example server.xml File
The server.xml file contains two variables, webapps_enable and webapps_file,
that are relevant to web applications.
webapps_enable
16
A true or false variable that allows you to enable or disable
web applications for a virtual server. If not present in a virtual
server definition, web applications are enabled by default.
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
The web-apps.xml File and Virtual Servers
webapps_file
The path to the web-apps.xml file for a virtual server.
The following server.xml file uses these variables:
<?xml version="1.0" encoding="UTF-8"?>
<!-- declare any variables to be used in the obj.conf file in the
ATTLIST below -->
<!DOCTYPE SERVER SYSTEM "server.dtd" [
<!ATTLIST VARS
docroot CDATA #IMPLIED
adminusers CDATA #IMPLIED
webapps_file CDATA #IMPLIED
webapps_enable CDATA #IMPLIED
accesslog CDATA #IMPLIED
user CDATA #IMPLIED
group CDATA #IMPLIED
chroot CDATA #IMPLIED
dir CDATA #IMPLIED
nice CDATA #IMPLIED
>
]>
<SERVER legacyls="ls1">
<VARS accesslog="/iws60/https-server.iplanet.com/logs/access"/>
<LS id="ls1" ip="0.0.0.0" port="80" security="off"
acceptorthreads="1">
<CONNECTIONGROUP id="group1" matchingip="default"
servername="acme.com" defaultvs="acme.com"/>
</LS>
<MIME id="mime1" file="mime.types"/>
<ACLFILE id="acl1"
file="/iws60/httpacl/generated.https-server.iplanet.com.acl"/>
<VSCLASS id="defaultclass" objectfile="obj.conf"
rootobject="default">
<VARS docroot="/iws60/docs"/>
<VS id="acme.com" connections="group1" mime="mime1"
aclids="acl1">
<VARS webapps_file="web-apps.xml" webapps_enable="on"/>
<USERDB id="default" database="default"/>
</VS>
</VSCLASS>
</SERVER>
For more information about the server.xml file, see Chapter 8, “Virtual Server
Configuration Files” in the NSAPI Programmer’s Guide for iPlanet Web Server.
Chapter 2
Web Applications
17
The web-apps.xml File and Virtual Servers
Example web-apps.xml File
Note that the !DOCTYPE declaration must be present and of the following format:
<!DOCTYPE vs PUBLIC "-//Sun Microsystems, Inc.; iPlanet//DTD
Virtual Server Web Applications 6.0//EN"
"http://developer.iplanet.com/webserver/dtds/iws-webapps_6_0.dtd">
If for some reason if this URL is not accessible, the DTD file is located here:
"file:/server_root/bin/https/dtds/iws-webapps_6_0.dtd"
On Windows NT, be sure to include the drive letter, as follows:
"file:/drive:/server_root_path/bin/https/dtds/iws-webapps_6_0.dtd"
The following web-apps.xml file configures a session manager and one web
application:
<?xml version="1.0" encoding="ISO-8859-1"?>
<!-- iWS 6.0 specific web application configuration. -->
<!DOCTYPE vs PUBLIC "-//Sun Microsystems, Inc.; iPlanet//DTD
Virtual Server Web Applications 6.0//EN"
"http://developer.iplanet.com/webserver/dtds/iws-webapps_6_0.dtd">
<vs>
<!-- Define global configuration -->
<!- Configure a session manager and tracking configuration -->
<session-manager
class=’com.iplanet.server.http.session.IWSSessionManager’
<init-param>
<param-name>maxSessions</param-name>
<param-value>1000</param-value>
</init-param>
<init-param>
<param-name>timeOut</param-name>
<param-value>1800</param-value>
</init-param>
<init-param>
<param-name>reapInterval</param-name>
<param-value>600</param-value>
</init-param>
<init-param>
<param-name>session-data-dir</param-name>
<param-value>/net/dotcom.com/sessions</param-value>
</init-param>
</session-manager>
18
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
The web-apps.xml File and Virtual Servers
<session-tracking use-cookies="true" />
<!-- Define the web applications for this virtual server-->
<!-- catalog application -->
<web-app uri="/catalog" dir="/webapps/catalog">
<!-- Specify a tempory directory. A path returned in the
"javax.servlet.context.tempdir" property; -- defaults to
WEB-INF/tmp. -->
<tempdir dir=’/var/catalog/tmp’/>
<!-- reload classes at every 5 minutes; also include mycatlog.jar
file in the classpath -->
<class-loader reload-interval=’300’
classpath=’/home/work/mycatalog.jar’ />
</web-app>
</vs>
web-apps.xml Element Reference
This section shows the elements allowed in a web-apps.xml file. These elements
are defined in the master dtd file.
auth-native
Configures a specific native user/group database for authentication and role
mapping. If this element is not specified, authentication is enabled using the native
default authentication database.
Subelements: none
Attributes:
authdb
The native authentication database. This database must also
be defined in the server.xml file in the database attribute
of a USERDB element, and in the dbswitch.conf file.
Chapter 2
Web Applications
19
The web-apps.xml File and Virtual Servers
class-loader
The class loader for the virtual server or the web application. There is a default
class loader for the virtual server if you don’t specify one. Classes loaded by the
virtual-server-level class loader are not dynamically reloaded.
You can use the ServletContext.getAttribute method to retrieve the class
loader and the class loader’s classpath or reload interval for a context. For more
information, see Chapter 7, “API Clarifications.”
Subelements: none
Attributes:
classpath
The classpath used by the class loader.
delegate
Specifies that the class loader for the virtual server or system
is called first to load a class. Allowed values are true and
false. The default is false.
reload-interval
The time interval in seconds within which the server checks
for web applications being modified. The default is 30.
description
A description of a parameter. Used within an init-param element. iPlanet Web
Server ignores this element.
Subelements: none
Attributes: none
filter, filter-mapping
These elements implement the Filter API from the Servlet 2.3 specification. Used
within a web-app element.
Although iPlanet Web Server 6.0 supports only the Servlet 2.2 API in the web.xml
file, the Filter API from the Servlet 2.3 specification is available in the
web-apps.xml file.
The filter and filter-mapping elements implement the Filter API. They are
both subelements of a web-app element in the web-apps.xml file. Except for their
file location, filter and filter-mapping are as described in the Servlet 2.3
specification. For more information, see:
http://java.sun.com/products/servlet/index.html
20
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
The web-apps.xml File and Virtual Servers
form-login-session
Configures form-based authentication for single sign-on across all web
applications in a virtual server. If not present, the default virtual server level
session manager is used.
Subelements: session-manager
Attributes:
cookie-name
The name of the cookie that tracks the session ID. The default
is iwsformloginid.
timeOut
The session timeout in seconds. The default is 600 (10
minutes).
init-param
Specifies an initialization parameter for the containing element. The attributes of
init-param depend on the object referenced by the containing element.
For example, if the containing element is session-manager and the session
manager is IWSSessionManager, the attributes of init-param are the initialization
parameters of IWSSessionManager.
Subelements: param-name, param-value, description
Attributes: variable
jsp-servlet
Configures JSP compilation behavior. For a description of the initialization
parameters, see “The JSP Command-Line Compiler,” on page 43.
Subelements: init-param
Attributes:
enable
Enables JSP. Allowed values are true and false. The default
is true.
Chapter 2
Web Applications
21
The web-apps.xml File and Virtual Servers
param-name
The name of a parameter. Used within an init-param element.
Subelements: none
Attributes: none
param-value
The value of a parameter. Used within an init-param element.
Subelements: none
Attributes: none
parameter-encoding
Advises the web server on how to decode parameters from forms.
Subelements: none
Attributes:
enc
Allowed values are auto (the default), none, or a specific encoding
such as utf8 or Shift_JIS:
any
supported
java character
encoding
A specific encoding, such as utf8 or Shift_JIS.
Set this option if you know the encoding that
servlet parameters use. A complete list is available
here:
http://java.sun.com/j2se/1.3/docs/guide
/intl/encoding.doc.html
none
22
Uses the system default encoding. Set this option if
the encoding of the servlet parameter data is the
same as the system default encoding.
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
The web-apps.xml File and Virtual Servers
auto
(Default) Tries to figure out the proper encoding
from, in order, 1) the charset if it is set in the
Content-Type header, 2) the
parameterEncoding attribute (see
“ServletRequest.setAttribute,” on page 73),
then 3) a hidden form field defined in
form-hint-field. Otherwise, the system
default encoding is used. Set this option to prevent
misinterpretation of non-ASCII characters in
servlet parameters.
When this property is set to auto, the server has to
convert native characters into a java byte array
before transforming them into the requested
encoding. Therefore, performance is slightly better
for none or a specific encoding.
form-hint-field
The name of the hidden field in the form that specifies the
encoding. The default is j_encoding.
If a servlet uses the ServletRequest.getParameter method to retrieve values in
form fields having non-UTF-8 characters, the enc attribute must be set to auto (the
default). Otherwise, the values extracted by the getParameter method are zeros or
are undefined. For more information see “ServletRequest.getParameter,” on page
74.
The enc attribute setting applies to how a servlet processes parameters after the
iPlanet Web Server receives a request. The URI that is sent to the server must
consist of only the standard ASCII set, especially if the request method is GET. All
other characters must be encoded.
For example, to encode a backslash, you would replace the backslash with a %
followed by the hexadecimal number corresponding to the backslash in the ASCII
character set, 5c. Therefore, vw\xyz becomes vw%5cxyz.
For more information, read section 2.2 of the following document from the URI
working group of the Internet Engineering Task Force:
http://www.ietf.org/rfc/rfc1738.txt
Chapter 2
Web Applications
23
The web-apps.xml File and Virtual Servers
response-buffer
Configures the initial and default size of the HTTP servlet’s response buffer. A
servlet can reconfigure its response buffer size using the setBufferSize method of
the ServletResponse object.
Subelements: none
Attributes:
flush-timeout
Forces the stream to flush the data if the specified number of
seconds has elapsed since the last flush. If set to 0 (the default)
or a negative number, the output stream doesn’t force a flush
unless the buffer is full.
size
The buffer size in bytes. The default is 8192.
response-cookie
Tells the server to respond with a specific cookie version.
Subelements: none
Attributes:
version
The cookie version. The default is 0.
role-mapping
Maps role-name values from web.xml to LDAP users, groups, or roles.
Subelements: none
Attributes:
map-to
24
Specifies whether to map role-name values from web.xml
to LDAP users or groups. Values are group (the default) and
user.
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
The web-apps.xml File and Virtual Servers
session-cookie
Sets parameters for the session cookie.
Subelements: none
Attributes:
domain
If this attribute is present, its value is tagged onto the cookie.
There is no default value.
is-secure
If set to true, the server sends the secure attribute in the
session cookie if the request came in a secure connection. The
default is false.
session-manager
The session manager for the web application. See Chapter 6, “Session Managers”
for the initialization parameters for each session manager.
If session-timeout is specified in web.xml, it overrides any session manager’s
timeOut initialization parameter. For details, see “session-timeout,” on page 15.
Subelements: init-param
Attributes:
class
The class for the session manager.
session-tracking
Determines the method of session tracking.
Subelements: none
Attributes:
use-cookies
Uses cookies for session tracking if true (the default).
Allowed values are true and false.
use-url-rewriting
Uses URL rewriting for session tracking if true (the default).
Allowed values are true and false.
Chapter 2
Web Applications
25
The web-apps.xml File and Virtual Servers
tempdir
A temporary directory used by the web application.
Subelements: none
Attributes:
dir
The temporary directory.
vs
The top-level element in the web-apps.xml file. Subelements other than web-app
set defaults for all web applications.
Subelements: auth-native, class-loader, form-login-session, jsp-servlet,
parameter-encoding, response-buffer, response-cookie, role-mapping,
session-manager, session-tracking, session-cookie, tempdir, web-app
Attributes: none
web-app
The web application. A web application is packaged in a WAR file and can contain
servlets, JSPs, HTML pages, class files, and other resources of an application.
The subelements of a web-app element override the equivalent subelements of the
containing vs element for that web application.
Subelements: auth-native, class-loader, filter, filter-mapping,
jsp-servlet, parameter-encoding, response-buffer, response-cookie,
role-mapping, session-manager, session-tracking, session-cookie, tempdir
Attributes:
26
dir
The directory where the web application contents are located.
uri
The URI that clients use to access the web application. This
URI can be a regular expression.
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Deploying a Web Application using wdeploy
Deploying a Web Application using wdeploy
Before you can deploy a web application manually, you must make sure that the
server_root/bin/https/httpsadmin/bin directory is in your path and that the
IWS_SERVER_HOME environment variable is set to your server_root directory.
You can use the wdeploy utility at the command line to deploy a WAR file into a
virtual server web application environment:
wdeploy deploy -u uri_path -i instance -v vs_id [-d directory] war_file
You can also delete a virtual server web application:
wdeploy delete -u uri_path -i instance -v vs_id hard|soft
You can also list the web application URIs and directories for a virtual server:
wdeploy list -i instance -v vs_id
The command parameters have the following meanings:
uri_path
The URI prefix for the web application.
instance
The server instance name.
vs_id
The virtual server ID.
directory
(optional) The directory to which the application is deployed, or from
which the application is deleted. If not specified for deployment, the
application is deployed to the document root directory.
hard|soft
Specifies whether the directory and the web-apps.xml entry are
deleted (hard) or just the web-apps.xml entry is deleted (soft).
war_file
The WAR file name.
CAUTION
If you deploy a web application and do not specify a directory, the
application is deployed to the document root directory. If you then
delete the application using the hard parameter, the document root
directory will be deleted.
When you execute the wdeploy deploy command, two things happen:
•
A web application with the given uri_path and directory gets added to the
web-apps.xml file.
Chapter 2
Web Applications
27
Deploying a Web Application using wdeploy
•
The .WAR file gets extracted at the target directory.
For example:
wdeploy deploy -u /hello -i server.iplanet.com -v acme.com
-d /iws60/https-server.iplanet.com/acme.com/web-apps/hello
/iws60/plugins/servlets/examples/web-apps/HelloWorld/HelloWorld.war
This utility results in the following web-apps.xml entry:
<vs>
<web-app uri="/hello"
dir="/iws60/https-server.iplanet.com/acme.com/webapps/hello"/>
</vs>
The /iws60/https-server.iplanet.com/acme.com/web-apps/hello directory
has the following contents:
colors
index.jsp
META-INF
WEB-INF/
web.xml
/classes/
HelloWorldServlet.class
HelloWorldServlet.java
SnoopServlet.class
SnoopServlet.java
Before you can run a web application that has been deployed, you must make sure
that the server.xml file for the server instance points to the web-apps.xml file for
your virtual server.
After you have deployed an application, you can access it from a browser as
follows:
http://vs_urlhost[:vs_port]/uri_path/[index_page]
The parts of the URL have the following meanings:
28
vs_urlhost
One of the urlhosts values for the virtual server.
vs_port
(optional) Only needed if the virtual server uses a non-default port.
uri_path
The same one you used to deploy the application. This is also the context
path.
index_page
(optional) The page in the application that end users are meant to access
first.
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Web Application Examples
For example:
http://acme.com:80/hello/index.jsp
or:
http://acme.com/hello/
Web Application Examples
iPlanet Web Server 6.0 comes with a set of example web applications. You can find
them at the following location:
server_root/plugins/servlets/examples/web-apps
This directory contains the following directories:
•
HelloWorld -- Contains a simple web application in a HelloWorld.war file.
•
filter-test -- Contains an example of the Filter API feature in a
filter-test.war file.
•
utility-taglib -- Contains an example JSP tag library in a
utility-taglib.war file. This tag library was created by the Jakarta project at
jakarta.apache.org.
You can deploy any of these examples using the wdeploy utility.
Chapter 2
Web Applications
29
Web Application Examples
30
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Chapter
3
Using Servlets
This chapter discusses how to enable and configure servlets in iPlanet Web Server
6.0. The sections in this chapter are:
•
What Does the Server Need to Run Servlets?
•
Using the User Interface
•
Enabling Servlets
•
Making Servlets Available to Clients
•
The <SERVLET> SHTML Tag
•
Servlet Output
•
Configuring JVM
•
Maximizing Servlet Performance
What Does the Server Need to Run Servlets?
iPlanet Web Server 6.0 includes all the files necessary for developing Java Servlets.
The servlet.jar file is in the iPlanet Web Server 6.0 installation directory at:
server_root/bin/https/jar
When compiling servlets, make sure the servlet.jar file is accessible to your
Java compiler. Include the servlet.jar file in your CLASSPATH.
iPlanet Web Server 6.0 includes the Java Runtime Environment (JRE) but not the
Java Development Kit (JDK) due to licensing restrictions. The server can run
servlets using the JRE only or the JDK. For information about installing the JDK,
see “What Does the Server Need to Run JSP?,” on page 37.
31
Using the User Interface
Using the User Interface
For information about using the user interface to specify settings for servlets, see
the following topics in the online help.
This page is located in the Web Server Administration Server on the Global
Settings tab.
•
The Configure JRE/JDK Paths Page
These pages are located in the Server Manager on the Java tab.
•
The Enable/Disable Servlets/JSP Page
•
The Configure JVM Attributes Page
•
The Delete Version Files Page
This page is located on the Virtual Servers tab in the Class Manager. (To open the
Class Manager, select the Manage Classes page on the Virtual Server Class tab in
the Server Manager, select a class from the list, then select the Manage button.)
•
The Java Web Apps Settings Page
Enabling Servlets
To enable servlets, select the Java tab in the Server manager, then select the
Enable/Disable Servlets/JSP tab. Check the Enable Java Globally box to enable
servlets for the entire server. Check the Enable Java for Class box to enable servlets
for a single virtual server class. You cannot enable servlets for a class unless Java is
globally enabled. By default, Java is globally enabled and enabled for each virtual
server class.
Making Servlets Available to Clients
You can make servlets accessible to clients in one of these two ways:
32
•
Include the servlets in web applications and deploy those web applications.
How to do this is described in Chapter 2, “Web Applications.”
•
Configure the servlets in the default virtual server. This is provided for
backward compatibility with iPlanet Web Server 4.x. How to do this is
described in Chapter 8, “Legacy Servlet and JSP Configuration.”
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
The <SERVLET> SHTML Tag
The <SERVLET> SHTML Tag
iPlanet Web Server 6.0 supports the <SERVLET> tag as introduced by Java Web
Server. This tag allows you to embed servlet output in an SHTML file. No
configuration changes are necessary to enable this behavior. If SSI and servlets are
both enabled, the <SERVLET> tag is enabled.
The <SERVLET> tag syntax is slightly different from that of other SSI commands; it
resembles the <APPLET> tag syntax:
<servlet name=name code=code codebase=path iParam1=v1 iParam2=v2>
<param name=param1 value=v3>
<param name=param2 value=v4>
.
.
</servlet>
If the servlet is part of a web application, the code parameter is required and other
parameters are ignored. The code parameter must include:
•
The value of the url-pattern element defined in the web.xml file for the web
application. For more information about web.xml, see the Servlet 2.2 API
specification:
http://java.sun.com/products/servlet/index.html
•
The value of the uri attribute defined in the web-apps.xml file for the web
application. For more information about web-apps.xml, see Chapter 2, “Web
Applications.”
For example, if you wanted to include the following in your SHTML file:
<servlet name=pparams code="/PrintApp/PrintParams">
</servlet>
you would need to include the following in your web-apps.xml file:
<web-app uri="/PrintApp"
dir="/iws60/https-server.iplanet.com/acme.com/webapps/PrintApp"/>
Chapter
3
Using Servlets
33
Servlet Output
You would also need to include the following in your web.xml file:
<servlet>
<servlet-name> pparams </servlet-name>
<servlet-class> PrintPackage.PrintParams </servlet-class>
</servlet>
<servlet-mapping>
<servlet-name> pparams </servlet-name>
<url-pattern> /PrintParams </url-pattern>
</servlet-mapping>
You must also include any servlet initialization parameters in the web.xml file.
For legacy (iPlanet Web Server 4.x) servlets, the code parameter specifies the
.class file for the servlet and is required. The codebase parameter is required if
the servlet is not defined in the servlets.properties file and the .class file is not
in the same directory as the HTML file containing the <SERVLET> tag. Legacy
servlets must be configured in the default virtual server and do not require a
web.xml file.
For more information about SSI commands, see the Programmer’s Guide for iPlanet
Web Server.
Servlet Output
When iPlanet Web Server is started in the background, which it is by default, the
System.out and System.err output of servlets are not sent to the web server’s
error log, because servlets are external to iPlanet Web Server.
On Unix, you can modify your server_root/https-server_id/start file to run iPlanet
Web Server in the foreground or to redirect servlet output. First enter the following
command from the server_root/https-server_id directory:
./start -shell
This command puts you in the server_root/bin/https/bin directory. Then enter
the following command:
./ns-httpd -d server_root/https-server_id/config
On NT, you can run iPlanet Web Server in the NT console, and thus in the
foreground, by including the following line in the magnus.conf file:
Init fn="nt-console-init" stdout=console stderr=console
34
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Configuring JVM
Configuring JVM
If necessary, you can configure parameters for JVM either by using the
Java>Configure JVM Attributes page in the Server Manager interface, or by editing
jvm12.conf. For more information about JVM settings, see Appendix C, “JVM
Configuration.”
The default settings in iPlanet Web Server for JVM are suitable for running servlets.
However, there may be times when you want to change the settings. For example,
if a servlet or bean file uses a JAR file, you can add the JAR location to the JVM
classpath.
Maximizing Servlet Performance
Consider the following guidelines for improving servlet performance:
•
The jvm12.conf file has a configuration parameter, jvm.stickyAttach.
Setting the value of this parameter to 1 causes threads to remember that they
are attached to the JVM, thus speeding up request processing by eliminating
AttachCurrentThread and DetachCurrentThread calls. It can, however, have
a side-effect: recycled threads which may be doing other processing can be
suspended by the garbage collector arbitrarily.
Thread pools can be used to eliminate this side effect for other subsystems. For
more information about thread pools, see the iPlanet Web Server Administrator’s
Guide.
•
Increase the front-end thread stack size in magnus.conf (via the StackSize
directive), or the respective pool stack size parameter if you’re using thread
pools. For more information, see the NSAPI Programmer’s Guide for iPlanet Web
Server.
•
Increase the heap size to help garbage collection: jvm.minHeapSize or
maxHeapSize or the Configure JVM Attributes page.
•
Ensure that your jvm.classpath is short (if you don't need some of the
examples). You can set jvm.include.CLASSPATH=0 so it won’t inherit the
CLASSPATH environment variable.
•
Sometimes, iPlanet Web Server 6.0 may run out of stack space if applications
use deep recursion when a JIT compiler is enabled, especially on UNIX
platforms where the default stack size is small, or in any cases where very
complex JSP pages are used.
Chapter
3
Using Servlets
35
Maximizing Servlet Performance
You can set the stack space using the StackSize directive in the magnus.conf
file. For more information, see the NSAPI Programmer’s Guide for iPlanet Web
Server.
•
The session ID generator, which is used for servlet sessions, employs
cryptographically strong unique random number generation algorithms. This
may present a performance problem on older, slow machines. For more
information, see Chapter 6, “Session Managers.”
NOTE
36
When running an SSL server without Java, you can improve
performance by enabling SmartHeap in the server’s start script.
However, SmartHeap is not compatible with Java.
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Chapter
4
Using JavaServer Pages
This chapter discusses how to enable and configure JavaServer Pages (JSPs) in
iPlanet Web Server 6.0. The sections in this chapter are:
•
What Does the Server Need to Run JSP?
•
Configuring JRE/JDK Paths
•
Using the User Interface
•
Enabling JSPs
•
Making JSPs Available to Clients
•
Deleting Cache Version Files
•
The JSP Command-Line Compiler
•
JSP Tag Libraries and Standard Portable Tags
What Does the Server Need to Run JSP?
iPlanet Web Server 6.0 includes the Java Runtime Environment (JRE) but not the
Java Development Kit (JDK) due to licensing restrictions. The server can run
servlets and precompiled JSPs using the JRE, but you need the JDK to develop new
JSPs or to deploy uncompiled JSPs. For information about precompiling JSPs, see
“The JSP Command-Line Compiler,” on page 43.
iPlanet Web Server 6.0 requires you to use the following recommended versions of
JRE/JDK or later versions, with different platforms requiring different versions, as
summarized in Table 4-1.
37
What Does the Server Need to Run JSP?
Table 4-1
Supported JRE/JDK Versions by Platform
Platform
JRE/JDK/JVM/JIT Version
Comments
Sun
Solaris
2.6, 2.8
Solaris VM (build
Solaris_JDK_1.2.2_07, native threads,
sunwjit)
Comment out -Xrs flag in jvm12.conf to generate
stack traces. For more information, see “Generating a
Stack Trace for Debugging,” on page 51.
For JVMPI based profiling (such as hprof) or debugging
(say attach Solaris dbx) purposes, use the reference
implementation downloadable from:
http://java.sun.com/products/jdk/1.2/jre/
Windows
NT 4.0
Java version 1.2.2 Classic VM (build
JDK-1.2.2_007, native threads,
symcjit)
HPUX
Java version 1.2.2.07 Classic VM
(build
1.2.2.07-00/12/08-PA_RISC1.1,
native threads, HP)
iPlanet also bundles a variant HotSpot VM (1.0.1fcs,
mixed mode, PA2.0 build
1.2.2.07-00/12/08-PA_RISC2.0). This VM is not enabled.
For further details on using this version, see:
http://www.unix.hp.com/java/infolibrary/
prog_guide/java2/hotspot.html
AIX
Java version 1.2.2 Classic VM (J2RE
1.2.2 IBM build ca122-20001206 (JIT
enabled: jitc))
Compaq
Tru64
Java version 1.2.2-8 Classic VM
(build
J2SDK.v.1.2.2:10/31/2000-18:00,
native threads, jit_122)
The Compaq version of iPlanet Web Server is available
from Compaq.
RedHat
Linux 6.2
Java version 1.2.2 Classic VM (build
Linux_JDK_1.2.2_FCS, native
threads, sunwjit)
This version of the JVM is from blackdown.org.
Check the iPlanet Web Server Installation and Migration Guide and the latest release
notes for updates on required JDK versions.
JDK 1.2 (and other JDK versions) are available from Sun Microsystems at:
http://java.sun.com/products/jdk/1.2/
You can specify the path to the JDK in either of the following ways:
•
38
You can specify the path during the server installation process.
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Configuring JRE/JDK Paths
When you install iPlanet Web Server 6.0, one of the dialog boxes in the
installation process asks if you want to use a custom Java Development Kit
(JDK), and if so, you can specify the path to it.
•
You can specify it after the server is installed.
To specify the path to the JDK, switch to the Web Server Administration
Server, select the Global Settings tab, and use the Configure JRE/JDK Paths
page, as discussed in the section “Configuring JRE/JDK Paths,” on page 39.
Whether you specify the path to the JDK during installation or later, the path is the
directory in which you installed the JDK.
Configuring JRE/JDK Paths
When you install iPlanet Web Server 6.0, you can choose to install the Java Runtime
Environment (JRE) that is shipped with the server, or you can specify a path to
your own JRE or the Java Development Kit (JDK).
The server can run servlets using the JRE, but it needs the JDK to run JSPs that are
not precompiled. The JDK is not bundled with the iPlanet Web Server, but you can
download it for free from Sun Microsystems at:
http://java.sun.com/products/jdk/1.2/
iPlanet Web Server 6.0 requires you to use version of the JDK listed in the section
“What Does the Server Need to Run JSP?,” on page 37.
Regardless of whether you choose to install the JRE or specify a path to the JDK
during installation, you can tell the iPlanet Web Server to switch to using either the
JRE or JDK at any time. Switch to the Web Server Administration Server, select the
Global Settings tab, and use the Configure JRE/JDK Paths page. You can also
change the path to the JDK in this page.
On the Configure JRE/JDK Paths page, supply values for the following fields if
you select the JDK radio button:
•
JDK Path
Enter the path for the JDK. This is the directory where you installed the JDK.
•
JDK Runtime Libpath
Enter the runtime library path for the JDK.
Chapter 4
Using JavaServer Pages
39
Configuring JRE/JDK Paths
•
JDK Runtime Classpath
The class path includes the paths to the directories and jar files needed to run
the servlet engine, the servlet examples, and any other paths needed by
servlets that you add. You can add new values to the existing class path, but
don’t delete the existing value since it includes paths that are essential for
servlet operation.
Supply values for the following fields if you select the JRE radio button:
•
JRE Path
Enter the path for the JRE. This is the directory where you installed the JRE.
•
JRE Runtime Libpath
Enter the runtime library path for the JRE.
NOTE
If you are not sure of the JDK runtime libpath, the JDK runtime
classpath, or the JRE runtime libpath, leave these fields blank to tell
the server to use the default paths.
It is easiest to use the Configure JRE/JDK Paths page to switch between the JRE
and the JDK, but you can also make the change programmatically, as follows:
•
On Unix:
Edit the file server_root/https-admserv/start-jvm.
If the server is currently using the JRE, this file has a variable NSES_JRE. To
enable the server to use a JDK, add the variable NSES_JDK whose value is the
JDK directory. You’ll also need to change the value of the NSES_JRE variable.
NSES_JDK should point to the installation directory for the JDK, while
NSES_JRE should point to the JRE directory in the installation directory for JDK
(that is, jdk_dir/jre).
•
On Windows NT:
Add the path to the Java libraries to the extrapath setting in magnus.conf.
Edit the NSES_JDK and NSES_JRE variables in the registry
HKEY_LOCAL_MACHINE/SOFTWARE/Netscape/Enterprise/6.0/. If the server is
enabled to use the JDK, both these variables are needed. If the server is to use
the JRE, only the NSES_JRE variable should be set.
40
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Using the User Interface
NSES_JDK should point to the installation directory for the JDK, while
NSES_JRE should point to the JRE directory in the installation directory for JDK
(that is, jdk_dir/jre).
CAUTION
Be very careful when editing these Windows NT registry entries.
Incorrect values may require you to reinstall iPlanet Web Server.
NOTE
To activate changes to the JRE/JDK paths, you must restart the
server from the On/Off option on the Preferences tab in the Server
Manager.
Using the User Interface
For information about using the user interface to specify settings for JSPs, see the
following topics in the online help.
This page is located in the Web Server Administration Server on the Global
Settings tab.
•
The Configure JRE/JDK Paths Page
These pages are located in the Server Manager on the Java tab.
•
The Enable/Disable Servlets/JSP Page
•
The Configure JVM Attributes Page
•
The Delete Version Files Page
This page is located on the Virtual Servers tab in the Class Manager. (To open the
Class Manager, select the Manage Classes page on the Virtual Server Class tab in
the Server Manager, select a class from the list, then select the Manage button.)
•
The Java Web Apps Settings Page
Chapter 4
Using JavaServer Pages
41
Enabling JSPs
Enabling JSPs
To enable JSPs, follow these steps:
1.
Enable servlets. Select the Java tab in the Server manager, then select the
Enable/Disable Servlets/JSP tab. Check the Enable Java Globally box to enable
servlets for the entire server. Check the Enable Java for Class box to enable
servlets for a single virtual server class. You cannot enable servlets for a class
unless Java is globally enabled. By default, Java is globally enabled and
enabled for each virtual server class.
2.
Include the jsp-servlet element with enable="true" in the web-apps.xml
file. For more information about the web-apps.xml file, see Chapter 2, “Web
Applications.”
3.
Add tools.jar to the JVM classpath. For more information, see Appendix C,
“JVM Configuration.”
Making JSPs Available to Clients
You can make JSPs accessible to clients in one of these two ways:
•
Include the JSPs in web applications and deploy those web applications. How
to do this is described in Chapter 2, “Web Applications.”
•
Configure the JSPs in the default virtual server. This is provided for backward
compatibility with iPlanet Web Server 4.x. How to do this is described in
Chapter 8, “Legacy Servlet and JSP Configuration.”
Deleting Cache Version Files
The server uses the following directory to cache information for JavaServer Pages
(JSP):
server_root/https-server_id/ClassCache/virtual_server_id/webapp_uri/
You can change the location of the JSP class cache using the scratchdir
initialization parameter of the jsp-servlet element in the web-apps.xml file. For
more information, see “Other JSP Initialization Parameters,” on page 47.
When the server serves a JSP page, it creates a .java and a .class file associated
with the JSP and stores them in the JSP class cache under the ClassCache directory.
42
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
The JSP Command-Line Compiler
The cache has a Version file containing a version number that the server uses to
determine the structure of the directories and files in the caches. You can clean out
the caches by simply deleting the version file.
When the server starts up, if it does not find the version file, it deletes the directory
structures for the corresponding caches and re-creates the version file. Next time
the server serves a JSP page, it recreates the JSP class cache.
You can delete the version file simply by deleting it from the ClassCache directory
as you would normally delete a file, or you can use the Java>Delete Version Files
page in the Server Manager to delete it. After deleting one or both version files, be
sure to restart the iPlanet Web Server to force it to clean up the appropriate caches
and to recreate the version file before the server serves any JSPs.
The JSP Command-Line Compiler
You can precompile JSPs for faster performance; this is recommended for
production servers. A command-line JSP compiler is included with iPlanet Web
Server. The JSP compiler is located under server_root/bin/https/bin (make sure
this directory is in your path). The IWS_SERVER_HOME environment variable must
be set to the server_root directory.
The format of the jspc command is as follows:
jspc [options] jsp_files
The jsp_files can be one of the following:
files
One or more JSP files to be compiled.
-webapp dir
A directory containing a web application. All JSPs in the
directory and its subdirectories are compiled. You cannot
specify a WAR, JAR, or ZIP file.
The options for the jspc command are:
-q
Enables quiet mode (same as -v0). Only fatal error messages
are displayed.
Chapter 4
Using JavaServer Pages
43
The JSP Command-Line Compiler
-v[level]
Enables verbose mode. The level is optional; the default is 2.
Possible level values are:
• 0 - fatal error messages only
• 1 - error messages only
• 2 - error and warning messages only
• 3 - error, warning, and informational messages
• 4 - error, warning, informational, and debugging
messages
-d dir
Specifies the output directory for the compiled JSPs. Package
directories are automatically generated based on the
directories containing the uncompiled JSPs. The default
top-level directory is the directory from which jspc is
invoked.
-dd dir
Specifies the literal output directory for the compiled JSPs.
Package directories are not made. The default is the directory
from which jspc is invoked.
-p name
Specifies the name of the target package for all specified JSPs,
overriding the default package generation performed by the
-d option.
-c name
Specifies the target class name of the first JSP compiled.
Subsequent JSPs are unaffected.
-mapped
Generates separate write calls for each HTML line and
comments that describe the location of each line in the JSP file.
By default, all adjacent write calls are combined and no
location comments are generated.
-die[code]
Causes the JVM to exit and generates an error return code if a
fatal error occurs. If the code is absent or unparsable it defaults
to 1.
-uribase dir
Specifies the URI directory to which compilations are relative.
Applies only to explicitly declared JSP files.
This is the location of each JSP file relative to the uriroot. If
this cannot be determined, the default is /.
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
The JSP Command-Line Compiler
-uriroot dir
Specifies the root directory against which URI files are
resolved. Applies only to explicitly declared JSP files.
If this option is not specified, all parent directories of the first
JSP page are searched for a WEB-INF subdirectory. The closest
directory to the JSP page that has one is used.
If none of the JSP’s parent directories have a WEB-INF
subdirectory, the directory from which jspc is invoked is
used.
-webinc file
Creates partial servlet mappings for the -webapp option,
which can be pasted into a web.xml file.
-webxml file
Creates an entire web.xml file for the -webapp option.
-ieplugin class_id
Specifies the Java plugin COM class ID for Internet Explorer.
Used by the <jsp:plugin> tags.
-genclass
Generates class files in addition to Java files. The JDK
tools.jar file must be in the JVM classpath.
The -webinc and -webxml options may not be useful for JSPs in iPlanet Web
Server.
For example, this command (all on one line) compiles the JSPs in the HelloWorld
web application:
jspc -d dir -genclass -webapp
server_root/plugins/servlets/examples/web-apps/HelloWorld
The compiled JSPs are written under dir/_jsps/. You can then put these class files
in a .JAR file.
Additional documentation for the JSP compiler is on the Jakarta site:
http://jakarta.apache.org/
Jasper and iPlanet Web Server 6.0 are not tightly integrated, so you might need to
edit the JVM Classpath (in the Configure JVM Attributes page of the Server
Manager or in the jvm12.conf file) when deploying JSPs using tag libraries, beans,
and so on. For more information about JVM settings, see Appendix C, “JVM
Configuration.”
Chapter 4
Using JavaServer Pages
45
The JSP Command-Line Compiler
Package Names Generated by the JSP
Compiler
When a JSP is compiled, a package is created for it. The package name starts with
_jsps and has each pathname component of the JSP prefixed with an underscore.
For example, the generated package name for /myjsps/hello.jsp is
_jsps._myjsps.
Because of the implicit package name associated with a generated servlet, you need
an explicit import directive when you use a bean in a JSP, especially if the bean
doesn’t have a package name. For example:
<%@page import="MyBean" %>
<jsp:useBean id="myBean" class="MyBean" />
Specifying that JSPs Are Precompiled
The jsp-servlet element in the web-apps.xml file allows you to tell iPlanet Web
Server that JSPs in a virtual server are precompiled. Include the following tags
inside a vs element:
<jsp-servlet enable="true">
<init-param>
<param-name>use-precompiled</param-name>
<param-value>true</param-value>
</init-param>
</jsp-servlet>
For more information about the web-apps.xml file, see Chapter 2, “Web
Applications.”
You do not need to install the JDK to run precompiled JSPs. However, you need the
JDK to develop new JSPs. For information about installing the JDK, see “What
Does the Server Need to Run JSP?,” on page 37.
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
JSP Tag Libraries and Standard Portable Tags
Other JSP Initialization Parameters
You can include the following initialization parameters under the jsp-servlet
element in your web-apps.xml file. The JSP compiler uses the default values for
parameters that are not included in the file.
keepgenerated
If set to true (the default), keeps the generated Java files. If
false, deletes the Java files.
largeFile
If set to true, static HTML is stored is a separate data file.
This is useful when a JSP is very large. The default is false.
scratchdir
The working directory created for storing all the generated
code. If this parameter is not specified, the default location is
server_root/https-server_id/ClassCache/virtual_server_id/
webapp_uri/.
mappedfile
If set to true, generates separate write calls for each HTML
line and comments that describe the location of each line in
the JSP file. By default, all adjacent write calls are combined
and no location comments are generated.
ieClassId
The Java plugin COM class ID for Internet Explorer. Used by
the <jsp:plugin> tags.
use-precompiled
If set to true, specifies that the JSPs in a virtual server are
precompiled and do not need to be compiled at runtime. The
default is false.
If set to true, changes to JSPs are not automatically reloaded.
You can compile JSPs using the command line JSP compiler,
put the classes in a JAR file, and put the JAR file in the
WEB_INF/lib directory of your web application.
JSP Tag Libraries and Standard Portable Tags
iPlanet Web Server supports tag libraries and standard portable tags. For more
information about tag libraries, see the JSP 1.1 specification at:
http://java.sun.com/products/jsp/download.html
Chapter 4
Using JavaServer Pages
47
JSP Tag Libraries and Standard Portable Tags
48
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Chapter
5
Debugging Servlets and JSPs
This appendix gives guidelines for debugging servlets and JSPs in iPlanet Web
Server 6.0. It includes the following sections:
•
Servlet Debugging
•
JSP Debugging
•
Generating a Stack Trace for Debugging
•
Using Forte for Java to Debug Servlets and JSPs
•
JPDA Options for Debugging
Debugging servlets and JSPs requires that you edit thejvm12.conf file as described
in this chapter. For more general information about this file, see Appendix C, “JVM
Configuration.”
Servlet Debugging
If the server has been instructed to use a JDK, you can do remote servlet
debugging. If the server is using the JRE, you need to switch it to using the JDK
before you can do remote debugging. For information on instructing the server to
use the JDK or the JRE, see the section “Configuring JRE/JDK Paths,” on page 39.
Assuming that the server is using the JDK, you can enable remote debugging by
following these steps:
1.
Make sure that the server is running in single-process mode. Single-process
mode is the default, but you can check in the file magnus.conf to make sure
that the MaxProcs parameter is not set to a value greater than 1. If you do not
see a setting for MaxProcs in magnus.conf, the default value of 1 is enabled for
it. For more information about single process mode versus multi-process
mode, see the iPlanet Web Server Administrator’s Guide.
49
JSP Debugging
2.
Set the following parameters in jvm12.conf as appropriate:
jvm.enableDebug=1
java.compiler=NONE
3.
To send exceptions to the client in addition to the log file, set the following
parameter. If the client is a browser, exceptions are displayed in the browser.
jvm.trace=7
4.
On some platforms, you may be required to specify the bootclasspath. For
example, for Solaris platforms, if Java 1.2 is in /java, you set it as follows in
jvm12.conf:
jvm.option=-Xbootclasspath:/java/lib/tools.jar:/java/jre/lib/rt.jar
5.
Start the server manually and record the password for remote debugging (this
is displayed on the console).
6.
Start the Java debugger:
jdb -host your_host -password the_password
You should be able to debug your Java classes now using the jdb command.
JSP Debugging
You can debug your JSPs by following these steps:
1.
Make sure that the server is running in single-process mode. Single-process
mode is the default, but you can check in the file magnus.conf to make sure
that the MaxProcs parameter is not set to a value greater than 1. If you do not
see a setting for MaxProcs in magnus.conf, the default value of 1 is enabled for
it. For more information about single process mode versus multi-process
mode, see the iPlanet Web Server Administrator’s Guide.
2.
Set the following parameters in jvm12.conf as appropriate:
java.compiler=NONE
jvm.trace=6
nes.jsp.enabledebug=1
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Generating a Stack Trace for Debugging
3.
To send exceptions to the client in addition to the log file, set the following
parameter. If the client is a browser, exceptions are displayed in the browser.
jvm.trace=7
Setting java.compiler=NONE includes line numbers of the Java source code in the
verbose output of the log files. Setting jvm.trace=6 or jvm.trace=7 enables
verbose output from the JSP compiler and the servlet engine. Setting
nes.jsp.enabledebug=1 makes iPlanet Web Server 6.0 generate debuggable Java
servlets from the JSPs.
Generating a Stack Trace for Debugging
You can generate a Java stack trace for debugging as described here:
http://developer.java.sun.com/developer/technicalArticles/Programming/Stacktrace/
Comment out the jvm.option=-Xrs flag (for reduced signal usage) in the
jvm12.conf file before generating the stack trace. If the -Xrs flag is used, the server
may simply dump core and restart when you send the signal to generate the trace.
For more about the jvm12.conf file and using jvm.option, see Appendix C, “JVM
Configuration.”
Using Forte for Java to Debug Servlets and JSPs
To set up iPlanet Web Server so you can use the Forte for Java debugger, follow
these steps:
1.
If you have not already done so, install the JDK version 1.2.x that iPlanet Web
Server requires as described in “What Does the Server Need to Run JSP?,” on
page 37. The specific version you need depends on your platform.
2.
Install the JDK version 1.3, available here:
http://java.sun.com/j2se/1.3/
Although iPlanet Web Server uses the JDK version 1.2.x, Forte for Java requires
version 1.3.
3.
Install Forte for Java, Community Edition 1.0, available here:
http://www.sun.com/forte/ffj/ce/
Chapter 5
Debugging Servlets and JSPs
51
Using Forte for Java to Debug Servlets and JSPs
4.
iPlanet strongly recommends that you also install the JPDA, available here:
http://java.sun.com/products/jpda/
5.
If you installed the JPDA, copy all the files from the jpda_install/bin directory
to the jdk1.2_install/jre/bin directory. Also copy the jpda.jar file from the
jpda_install/lib directory to the jdk1.2_install/jre/lib/ext directory.
Note that the JPDA runs on JDK 1.2, not 1.3.
6.
On Windows NT, add the following line to the magnus.conf file to enable the
NT console:
Init fn="nt-console-init" stdout=console stderr=console
7.
Edit the jvm12.conf file to enable remote debugging. If you did not install the
JPDA, add the following lines:
jvm.enableDebug=1
jvm.compiler=NONE
If you installed the JPDA, add the following lines:
jvm.enableDebug=1
jvm.compiler=NONE
jvm.option=-classic
jvm.option=-Xnoagent
jvm.option=-Xrunjdwp:transport=dt_socket,server=y,suspend=n
8.
Start Forte for Java, and mount the directory that contains the servlet or JSP
you want to debug.
9.
Start iPlanet Web Server. You will see a line similar to the following displayed
in the console:
Listening for transport dt_socket at address: port_number
Write down this port_number.
10. In Forte for Java, select the Debug menu and the Attach to VM... option. Type
the port_number in the Port: text box, then select OK.
You are now ready to debug your servlet or JSP.
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
JPDA Options for Debugging
JPDA Options for Debugging
A list of debugging options that you can include in the jvm12.conf file if the JPDA
is installed is available here:
http://java.sun.com/products/jpda/doc/conninv.html#Invocation
Chapter 5
Debugging Servlets and JSPs
53
JPDA Options for Debugging
54
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Chapter
6
Session Managers
Session objects maintain state and user identity across multiple page requests over
the normally stateless HTTP protocol. A session persists for a specified time
period, across more than one connection or page request from the user. A session
usually corresponds to one user, who may visit a site many times. The server can
maintain a session either by using cookies or by rewriting URLs. Servlets can
access the session objects to retrieve state information about the session.
This appendix has the following sections:
•
Session Overview
•
Specifying a Session Manager
•
IWSSessionManager
•
MMapSessionManager (Unix Only)
•
Deprecated Session Managers
•
Load Balancing, Session Failover, and Session IDs
Session Overview
An HTTP session represents the server’s view of the session. The server considers a
session new under these conditions:
•
The client does not yet know about the session.
•
The session has not yet begun.
A session manager automatically creates new session objects whenever a new
session starts. In some circumstances, clients do not join the session, for example, if
the session manager uses cookies and the client does not accept cookies.
55
Specifying a Session Manager
iPlanet Web Server 6.0 comes with these session managers for creating and
managing sessions:
•
IWSSessionManager -- the default session manager, which can use a database
or a file store for persistent sessions, and can run in single-process or
multi-process mode.
•
MMapSessionManager (Unix Only) -- a session manager for running the
server in multi-process mode. Does not support distributed sessions.
•
SimpleSessionManager -- a deprecated simple session manager. Does not
support distributed sessions.
•
JdbcSessionManager -- a deprecated session manager that stores session
information in a database using the JDBC API and that supports distributed
sessions.
Multi-process mode is supported only on Unix platforms. All multi-process mode
features of session managers are ignored on Windows NT.
iPlanet Web Server 6.0 also allows you to develop your own session managers and
load them into the server. The source code files for session manager classes are
provided as a starting point for you to define your own session managers if
desired. These Java files are in the directory
server_root/plugins/servlets/iws-apis/sessions.
Specifying a Session Manager
By default iPlanet Web Server uses IWSSessionManager as the session manager for
servlets. You can change the session manager in any of the following ways:
•
Edit the file web-apps.xml in the directory server_id/config.
Add a session-manager element within the web-app element for the servlet or
JSP as in the following example:
<session-manager
class=’com.iplanet.server.http.session.YourSesMgr’
<init-param>
<param-name>maxSessions</param-name>
<param-value>1000</param-value>
</init-param>
<init-param>
<param-name>timeOut</param-name>
<param-value>1800</param-value>
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Specifying a Session Manager
</init-param>
<init-param>
<param-name>reapInterval</param-name>
<param-value>600</param-value>
</init-param>
</session-manager>
For more information about the web-apps.xml file, see Chapter 2, “Web
Applications.”
•
Use the Legacy Servlets>Configure Global Servlet Attributes page in the Server
Manager interface.
In the Session Manager field, specify the session manager, and, if appropriate,
specify parameters for the session manager in the Session Manager Args field.
•
Edit the file servlets.properties in the directory server_id/config. This will
apply to the default virtual server only.
Add a line specifying a value for servlets.sessionmgr and, if appropriate,
also add a line specifying the parameters for the session manager. For example:
servlets.sessionmgr=com.iplanet.server.http.session.YourSesMgr
servlets.sessionmgr.initArgs=maxSessions=20,timeOut=300,reapInterval=150
•
Edit the file contexts.properties in the directory server_id/config. This will
apply to the default virtual server only.
Add a line specifying a value for context.context_name.sessionmgr and, if
appropriate, also add a line specifying the parameters for the session manager.
For example:
context.global.sessionmgr=com.iplanet.server.http.session.YourSesMgr
context.global.sessionmgr.initArgs=maxSessions=20,timeOut=300
You can change the global context or define a new context and assign specific
servlets to it. For more information, see Chapter 8, “Legacy Servlet and JSP
Configuration.”
Chapter
6
Session Managers
57
IWSSessionManager
IWSSessionManager
The IWSSessionManager is the default session manager.
IWSSessionManager works in both single process and multi-process mode. It can
be used for sharing session information across multiple processes possibly running
on different machines. The MaxProcs directive in the magnus.conf file determines
whether the server is running in single process mode or multi-process mode. For
more information, see the NSAPI Programmer’s Guide for iPlanet Web Server.
For session persistence, IWSSessionManager can use a database or a distributed
file system (DFS) path that is accessible from all servers in a server farm. Each
session is serialized to the database or distributed file system. You can also create
your own persistence mechanism.
If iPlanet Web Server is running in single-process mode, then by default, no session
persistence mode is defined and therefore sessions are not persistent.
If iPlanet Web Server is running in multi-process mode, sessions are persistent by
default. If a persistence mode is not defined, IWSSessionManager uses a DFS.
Multi-process mode is supported only on Unix platforms. All multi-process mode
features of IWSSessionManager are ignored on Windows NT.
Parameters for IWSSessionManager
IWSSessionManager takes the following parameters:
•
maxSessions - the maximum number of sessions maintained by the session
manager at any given time. The session manager refuses to create any more
new sessions if there are already maxSessions number of sessions present at
that time. The default value is 1000.
•
timeOut - the amount of time in seconds after a session is accessed by the client
before the session manager destroys it. Those sessions that haven’t been
accessed for at least timeOut seconds are destroyed by the reaper method. The
default value is 1800 (30 minutes).
If session-timeout is specified in web.xml, it overrides this timeOut
parameter value. For details, see “session-timeout,” on page 15.
•
58
reapInterval - the amount of time in seconds that the SessionReaper thread
sleeps before calling the reaper method again. The default value is 600 (10
minutes).
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
IWSSessionManager
•
maxLocks - the number of cross-process locks to use for synchronizing access
to individual sessions across processes. The default value is 10. This default
value is used if the value 0 is specified. This parameter is ignored in
single-process mode.
•
session-data-store - the name of the class that determines the means of
session persistence. The classes supplied with iPlanet Web Server are:
❍
com.iplanet.server.http.session.JdbcStore
❍
com.iplanet.server.http.session.FileStore
If you do not specify the session-data-store parameter, sessions are not
persistent in single-process mode, and FileStore is the default in
multi-process mode.
The JdbcStore and FileStore classes are subclasses of the
SessionDataStore class. You can create your own class that implements
session persistence by extending SessionDataStore.
NOTE
Prior to using JdbcStore, you must create the table in which the
session information is stored. The name of the table is specified by
the table parameter, and the table’s four columns are specified by
the accessTimeColumn, timeOutColumn, sessionIdColumn, and
valueColumn parameters.
If the session-data-store parameter is set to the JdbcStore or FileStore class,
IWSSessionManager takes the following additional parameter:
•
session-failover-enabled - specifies whether sessions are reloaded from
the persistent store for every request, and always forced to true in
multi-process mode.
If the session-data-store parameter is set to the FileStore class,
IWSSessionManager takes the following additional parameter:
•
session-data-dir - the directory in which session data for all servers and
web applications is kept.
If the session-data-dir parameter is not specified, the following directory is
used by default:
server_root/server_id/SessionData/virtual_server_id/web_app_URI
If the session-data-store parameter is set to the JdbcStore class,
IWSSessionManager takes the following additional parameters:
Chapter
6
Session Managers
59
IWSSessionManager
•
provider - the JDBC driver (the default is sun.jdbc.odbc.JdbcOdbcDriver).
For more information about the JDBC API, see the following web site:
http://java.sun.com/products/jdbc/index.html
NOTE
The JdbcStore class does not recognize JDBC driver classes
assigned to the classpath attribute of the class-loader element
in web-apps.xml. Assign them to the jvm.classpath variable in
the jvm12.conf file instead. For more information, see Appendix C,
“JVM Configuration.”
•
url - the data source (the default is jdbc:odbc:LocalServer).
•
table - name of the SQL table that store sessions (the default is sessions).
•
username - the login username for the database.
•
password - the login password for the database.
•
reaperActive - tells the session manager whether to run session reaper to
remove expired sessions from the database when true, which is the default
value. It is recommended that only one server in the cluster be running the
reaper.
•
accessTimeColumn - the name of the column that holds the last access time in
minutes (the default name is AccessTime). The SQL type is NUMERIC(9).
•
timeOutColumn - the name of the column that holds the session timeout in
minutes (the default name is TimeOut). The SQL type is NUMERIC(9).
•
sessionIdColumn - the name of the column that holds the session ID (the
default name is SessionID). The SQL type is VARCHAR(100).
•
valueColumn - the name of the column that holds the session object (the
default name is Value). The SQL type is VARBINARY(4096). This column must
be large enough to accommodate all your session data.
Each type of operation on the database that handles session information (looking
up, inserting, updating, and deleting) is performed by a corresponding dedicated
connection. Each of these connections has a precompiled SQL statement for higher
performance. The following parameters allow you to customize the number of
dedicated connections that perform each of the operations.
•
60
lookupPool - the number of connections that perform lookup operations (the
default is 4 connections).
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
IWSSessionManager
•
insertPool - the number of connections that perform insert operations (the
default is 4 connections).
•
updatePool - the number of connections that perform update operations (the
default is 4 connections).
•
deletePool - the number of connections that perform delete operations (the
default is 2 connections).
Enabling IWSSessionManager
You may want to enable IWSSessionManager to change its default parameters.
You can also enable IWSSessionManager for a particular context if the server is
running in single process mode. To enable iPlanet Web Server to use
IWSSessionManager, do any of the following:
•
Edit the file web-apps.xml in the directory server_id/config.
Add a session-manager element within the web-app element for the servlet or
JSP as in the following example:
<session-manager
class=’com.iplanet.server.http.session.IWSSessionManager’
<init-param>
<param-name>maxSessions</param-name>
<param-value>1000</param-value>
</init-param>
<init-param>
<param-name>timeOut</param-name>
<param-value>1800</param-value>
</init-param>
<init-param>
<param-name>reapInterval</param-name>
<param-value>600</param-value>
</init-param>
<init-param>
<param-name>session-data-dir</param-name>
<param-value>/net/dotcom.com/sessions</param-value>
</init-param>
</session-manager>
For more information about the web-apps.xml file, see Chapter 2, “Web
Applications.”
Chapter
6
Session Managers
61
MMapSessionManager (Unix Only)
•
Use the Legacy Servlets>Configure Global Servlet Attributes page in the Server
Manager interface.
In the Session Manager field specify:
com.iplanet.server.http.session.IWSSessionManager
You can also specify parameters for the session manager in the Session
Manager Args field, for example:
maxSessions=20,session-data-dir=/net/dotcom.com/sessions
Source Code for IWSSessionManager
The IWSSessionManager creates an IWSHttpSession object for each session. The
source files for IWSSessionManager.java and IWSHttpSession.java are in the
server_root/plugins/servlets/iws-apis/sessions directory. The source code
files for IWSSessionManager.java and IWSHttpSession.java are provided so
you can use them as the starting point for defining your own session managers and
session objects.
IWSSessionManager extends IWSHttpSessionManager. The class file for
IWSHttpSessionManager is in the JAR file NSServletLayer.jar in the directory
server_root/bin/https/jar. The IWSSessionManager implements all the methods
in IWSHttpSessionManager that need to be implemented, so you can use
IWSSessionManager as an example of how to extend IWSHttpSessionManager.
When compiling your subclass of IWSSessionManager or
IWSHttpSessionManager, be sure that the JAR file NSServletLayer.jar is in
your compiler’s classpath.
The JdbcStore.java and FileStore.java source files and the source file for the
parent class, SessionDataStore.java, are provided so you can modify the session
persistence mechanism of IWSSessionManager. These files are also located in the
directory server_root/plugins/servlets/iws-apis/sessions.
MMapSessionManager (Unix Only)
This is a persistent memory map (mmap) file based session manager that works in
both single process and multi-process mode.
The MaxProcs directive in the magnus.conf file determines whether the server is
running in single process mode or multi-process mode. For more information, see
the NSAPI Programmer’s Guide for iPlanet Web Server.
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
MMapSessionManager (Unix Only)
Parameters
MMapSessionManager takes the following parameters:
•
maxSessions - the maximum number of sessions maintained by the session
manager at any given time. The session manager refuses to create any more
new sessions if there are already maxSessions number of sessions present at
that time. The default value is 1000.
•
maxValuesPerSession - the maximum number of values or objects a session
can hold. The default value is 10.
•
maxValueSize - the maximum size of each value or object that can be stored in
the session. The default value is 4096.
•
timeOut - the amount of time in seconds after a session is last accessed by the
client before the session manager destroys it. Those sessions that haven’t been
accessed for at least timeOut seconds are destroyed by the reaper method. The
default value is 1800 (30 minutes).
If session-timeout is specified in web.xml, it overrides this timeOut
parameter value. For details, see “session-timeout,” on page 15.
•
reapInterval - the amount of time in seconds that the SessionReaper thread
sleeps before calling the reaper method again. The default value is 600 (10
minutes).
•
maxLocks - the number of cross-process locks to use for synchronizing access
to individual sessions across processes. The default value is 1. This default
value is used if the value 0 is specified. This parameter is ignored in
single-process mode.
Enabling MMapSessionManager
You may want to enable MMapSessionManager to change its default parameters.
You can also enable MMapSessionManager for a particular context if the server is
running in single process mode. To enable iPlanet Web Server to use
MMapSessionManager, do any of the following:
•
Use the Legacy Servlets>Configure Global Servlet Attributes page in the Server
Manager interface.
In the Session Manager field specify:
com.iplanet.server.http.session.MMapSessionManager
Chapter
6
Session Managers
63
MMapSessionManager (Unix Only)
You can also specify parameters for the session manager in the Session
Manager Args field, for example:
maxSessions=20,maxValueSize=1024,timeOut=300
•
Edit the file servlets.properties in the directory server_id/config. This will
apply to the default virtual server only.
Add a line specifying a value for servlets.sessionmgr and a line specifying
the parameters for the session manager:
servlets.sessionmgr=com.iplanet.server.http.session.MMapSessionManager
servlets.sessionmgr.initArgs=maxSessions=20,maxValueSize=1024,timeOut=300
•
Edit the file contexts.properties in the directory server_id/config. This will
apply to the default virtual server only.
Add a line specifying a value for context.context_name.sessionmgr and a
line specifying the parameters for the session manager:
context.global.sessionmgr=com.iplanet.server.http.session.MMapSessionManager
context.global.sessionmgr.initArgs=maxSessions=20,maxValueSize=1024,timeOut=300
You can change the global context or define a new context and assign specific
servlets to it. For more information, see Chapter 8, “Legacy Servlet and JSP
Configuration.”
This session manager can only store objects that implement
java.io.Serializable.
Deleting SessionData Version Files
If the server uses the MMapSessionManager session manager, it stores persistent
session information in the SessionData directory. This cache has a Version file
containing a version number that the server uses to determine the structure of the
directories and files in the caches. You can clean out the caches by simply deleting
the version file.
When the server starts up, if it does not find the version file, it deletes the directory
structures for the corresponding caches and re-creates the version file. The next
time the server serves a servlet while using MMapSessionManager session manager,
it recreates the session data cache.
You can delete the version file simply by deleting it from the SessionData
directory as you would normally delete a file, or you can use the Java>Delete
Version Files page in the Server Manager to delete it. After deleting the version file,
be sure to restart the iPlanet Web Server to force it to clean up the appropriate
caches and to recreate the version file before the server serves any servlets.
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Deprecated Session Managers
Deprecated Session Managers
The SimpleSessionManager and the JdbcSessionManager are provided for
backward compatibility with iPlanet Web Server 4.x.
NOTE
The parent class of the deprecated session managers is also
deprecated and is included for backward compatibility only:
com.netscape.server.http.session.NSHttpSessionManager
Extend the following class instead:
com.iplanet.server.http.session.IWSHttpSessionManager
SimpleSessionManager
The SimpleSessionManager works only in single process mode. Its sessions are
not persistent, that is, all sessions are lost when the server is stopped.
NOTE
The SimpleSessionManager is deprecated and is included for
backward compatibility only. Use IWSSessionManager with no
session persistence instead.
Parameters
The SimpleSessionManager class takes the following parameters:
•
maxSessions - the maximum number of sessions maintained by the session
manager at any given time. The session manager refuses to create any more
new sessions if there are already maxSessions number of sessions present at
that time. The default value is 1000.
•
timeOut - the amount of time in seconds after a session is accessed by the client
before the session manager destroys it. Those sessions that haven’t been
accessed for at least timeOut seconds are destroyed by the reaper method. The
default value is 1800 (30 minutes).
If session-timeout is specified in web.xml, it overrides this timeOut
parameter value. For details, see “session-timeout,” on page 15.
•
reapInterval - the amount of time in seconds that the SessionReaper thread
sleeps before calling the reaper method again. The default value is 600 (10
minutes).
Chapter
6
Session Managers
65
Deprecated Session Managers
Enabling SimpleSessionManager
You may want to enable SimpleSessionManager to change its default parameters.
You can also enable SimpleSessionManager for a particular context if the server is
running in multi-process mode. To enable the iPlanet Web Server to use
SimpleSessionManager, do any of the following:
•
Use the Legacy Servlets>Configure Global Servlet Attributes page in the Server
Manager interface.
In the Session Manager field specify:
com.netscape.server.http.session.SimpleSessionManager
You can also specify parameters for the session manager in the Session
Manager Args field, for example:
maxSessions=20,timeOut=300,reapInterval=150
•
Edit the file servlets.properties in the directory server_id/config. This will
apply to the default virtual server only.
Add a line specifying a value for servlets.sessionmgr and a line specifying
the parameters for the session manager:
servlets.sessionmgr=com.netscape.server.http.session.SimpleSessionManager
servlets.sessionmgr.initArgs=maxSessions=20,timeOut=300,reapInterval=150
•
Edit the file contexts.properties in the directory server_id/config. This will
apply to the default virtual server only.
Add a line specifying a value for context.context_name.sessionmgr and a
line specifying the parameters for the session manager:
context.global.sessionmgr=com.netscape.server.http.session.SimpleSessionManager
context.global.sessionmgr.initArgs=maxSessions=20,timeOut=300,reapInterval=150
You can change the global context or define a new context and assign specific
servlets to it. For more information, see Chapter 8, “Legacy Servlet and JSP
Configuration.”
JdbcSessionManager
This is a persistent JDBC-based session manager that works in both single process
and multi-process modes. It can be used to store sessions in a custom database,
which can then be shared across multiple processes possibly running on different
machines.
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Deprecated Session Managers
NOTE
The JDBCSessionManager is deprecated and is included for
backward compatibility only. Use IWSSessionManager with
JdbcStore session persistence instead.
This sample JDBC session manager is not written, tested, or intended for
production use. It is provided so that you can customize its behavior to suit your
own needs.
JdbcSessionManager has been tested with a standard JDBC-ODBC driver against
Microsoft SQL Server 7.0SP1. You must set up the ODBC source, database, and
table for the session manager to use. It is recommended that the Session ID column
be indexed for higher lookup performance.
Parameters
JdbcSessionManager takes the following parameters:
•
timeOut - the amount of time in seconds after a session is accessed by the client
before the session manager destroys it. Those sessions that haven’t been
accessed for at least timeOut seconds are destroyed by the reaper method. The
default value is 1800 (30 minutes).
If session-timeout is specified in web.xml, it overrides this timeOut
parameter value. For details, see “session-timeout,” on page 15.
•
provider - the JDBC driver (the default is sun.jdbc.odbc.JdbcOdbcDriver).
For more information about the JDBC API, see the following web site:
http://java.sun.com/products/jdbc/index.html
NOTE
The JdbcStore class does not recognize JDBC driver classes
assigned to the classpath attribute of the class-loader element
in web-apps.xml. Assign them to the jvm.classpath variable in
the jvm12.conf file instead. For more information, see Appendix C,
“JVM Configuration.”
•
url - the data source (the default is jdbc:odbc:LocalServer).
•
table - name of the SQL table that store sessions (the default is sessions).
•
username - the login username for the database.
•
password - the login password for the database.
Chapter
6
Session Managers
67
Deprecated Session Managers
•
reaperActive - tells the session manager whether to run session reaper to
remove expired sessions from the database when true, which is the default
value. It is recommended that only one server in the cluster be running the
reaper.
•
accessTimeColumn - the name of the column that holds the last access time in
minutes (the default name is AccessTime). The SQL type is NUMERIC(9).
•
sessionIdColumn - the name of the column that holds the session ID (the
default name is SessionID). The SQL type is VARCHAR(100).
•
valueColumn - the name of the column that holds the session object (the
default name is Value). The SQL type is VARBINARY(4096). This column must
be large enough to accommodate all your session data.
Each type of operation on the database that handles session information (looking
up, inserting, updating, and deleting) is performed by a corresponding dedicated
connection. Each of these connections has a precompiled SQL statement for higher
performance. The following parameters allow you to customize the number of
dedicated connections that perform each of the operations.
•
lookupPool - the number of connections that perform lookup operations (the
default is 4 connections).
•
insertPool - the number of connections that perform insert operations (the
default is 4 connections).
•
updatePool - the number of connections that perform update operations (the
default is 4 connections).
•
deletePool - the number of connections that perform delete operations (the
default is 2 connections).
Enabling JdbcSessionManager
You may want to enable JdbcSessionManager to change its default parameters.
You can also enable JdbcSessionManager for a particular context if the server is
running in single process mode. To enable iPlanet Web Server to use
JdbcSessionManager, do any of the following:
•
Use the Legacy Servlets>Configure Global Servlet Attributes page in the Server
Manager interface.
In the Session Manager field specify:
com.netscape.server.http.session.JdbcSessionManager
You can also specify parameters for the session manager in the Session
Manager Args field, for example:
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Load Balancing, Session Failover, and Session IDs
timeOut=1200,username=mysession,password=mypassword
•
Edit the file servlets.properties in the directory server_id/config. This will
apply to the default virtual server only.
Add a line specifying a value for servlets.sessionmgr and a line specifying
the parameters for the session manager:
servlets.sessionmgr=com.netscape.server.http.session.JdbcSessionManager
servlets.sessionmgr.initArgs=timeOut=1200,username=mysession,password=mypassword
•
Edit the file contexts.properties in the directory server_id/config. This will
apply to the default virtual server only.
Add a line specifying a value for context.context_name.sessionmgr and a
line specifying the parameters for the session manager:
context.global.sessionmgr=com.netscape.server.http.session.JdbcSessionManager
context.global.sessionmgr.initArgs=timeOut=1200,username=mysession,password=mypassword
You can change the global context or define a new context and assign specific
servlets to it. For more information, see Chapter 8, “Legacy Servlet and JSP
Configuration.”
This session manager can only store objects that implement
java.io.Serializable.
Load Balancing, Session Failover, and Session
IDs
iPlanet Web Server 6.0 supports server farm (or cluster) configurations with
off-the-shelf, session-aware front-end load balancers such as Resonate. iPlanet Web
Server 6.0 implements sticky sessions by prefixing the node_id of the server host
that generated the session to JSESSIONID, the session cookie name specified in the
Servlets 2.2 specification, as follows:
Set-Cookie: JSESSIONID=node_id-3ad%253A39c02099%253Ad19e53e2a2;
path=/app;expires=Thu, 14-Sep-2000 01:19:30 GMT
This enables the front-end load balancer to forward future requests to the same
host that generated the session.
If the session manager used by a cluster supports distributed sessions, an alternate
server can pick up a session created by a server that crashed. The
IWSSessionManager supports distributed sessions if its session-data-store
parameter has a value that defines the mode of session persistence. The
JdbcSessionManager also supports distributed sessions.
Chapter
6
Session Managers
69
Load Balancing, Session Failover, and Session IDs
70
NOTE
The session ID generator, which is used for servlet sessions,
employs cryptographically strong unique random number
generation algorithms. This may present a performance problem on
older, slow machines. The Session Manager API allows you to
redefine the random ID generation method and customize it to
your particular needs (see the IWSSessionManager.java example
file described in “Source Code for IWSSessionManager,” on page
62).
NOTE
iPlanet Web Server session managers generate session IDs with a
maximum length of 108 ASCII characters.
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Chapter
7
API Clarifications
This appendix clarifies ways in which the Servlet 2.2 API specification is
implemented in iPlanet Web Server 6.0 in the following sections:
•
Clarification of HttpSession Scope
•
Clarifications for Using Methods
•
Other Useful Information
Clarification of HttpSession Scope
The Servlet 2.2 API Specification is open to interpretation in regard to the scope of
HttpSession objects.
By default, iPlanet Web Server marks the session tracking cookie’s path to that of
the context or application’s contextPath. This results in the browser not replaying a
session cookie to an application for which it is not intended. Hence, the
HttpSession objects are scoped appropriately.
However, if servlet A in one context dispatches a request to servlet B in a different
context, the specification is open to interpretation. By default iPlanet Web Server
permits this, and you must make sure that the attributes placed in the HttpSession
object are loaded by a class loader that is common to the applications involved.
You can use a virtual-server-level class loader or the system class loader, although
this is not generally recommended.
To allow different applications to share sessions and session attributes:
•
Use a common session manager at the virtual server level.
<vs>
<session-manager class="..." />
</vs>
71
Clarifications for Using Methods
•
Make sure that the session attributes are loaded by the virtual-server-level
class loader. Add any common beans and so on that are going to be used as
session attributes to the classpath there.
<vs>
<class-loader classpath="/myapps/sessionattrs.jar" />
</vs>
This configuration lets you share sessions across all applications within a virtual
server or none at all. For iPlanet Web Server 6.0, there is no way that only a set of
applications can share the same session data.
Clarifications for Using Methods
This section provides clarifications for using the following Servlet 2.2 API methods
with iPlanet Web Server 6.0:
•
HttpServlet.service
•
ServletContext.getAttribute
•
ServletRequest.setAttribute
•
ServletRequest.getParameter
•
ServletResponse.getOutputStream and getWriter
•
RequestDispatcher.forward and include
For the official documentation for the methods discussed here (and for all servlet
API methods) see the Servlets API Javadoc published by Sun Microsystems at:
http://java.sun.com/products/servlet/2.2/javadoc/index.html
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Clarifications for Using Methods
HttpServlet.service
public void service(ServletRequest req, ServletResponse res) throws
ServletException, java.io.IOException
This method dispatches client requests to the protected service method.
Clarification
Servlets may create additional threads to handle their service logic. However, the
API functions exposed by these objects must be accessed by either the request
handling thread or one of the threads the servlet created, but not by both
simultaneously.
ServletContext.getAttribute
public java.lang.Object getAttribute(java.lang.String name)
Returns the servlet container attribute with the given name, or null if there is no
attribute by that name.
Clarification
To obtain the context class loader (a java.lang.ClassLoader object), use the
com.iplanet.server.http.servlet.classloader attribute. To obtain the
context class loader’s classpath (a java.lang.String object), use the
com.iplanet.server.http.servlet.classpath attribute.To obtain the context
class loader’s reload interval (a java.lang.Integer object), use the
com.iplanet.server.http.servlet.reload-interval attribute.
ServletRequest.setAttribute
public void setAttribute(java.lang.String name, java.lang.Object o)
Stores an attribute in this request. Attributes are reset between requests. This
method is most often used in conjunction with RequestDispatcher.
Clarification
You can set the com.iplanet.server.http.servlet.parameterEncoding
attribute in the request object to allow the getParameter method to know the
encoding of the parameters it extracts.
Chapter
7
API Clarifications
73
Clarifications for Using Methods
ServletRequest.getParameter
public java.lang.String getParameter(java.lang.String name)
Retrieves the value associated with a parameter name.
Clarification
When your form fields contain non-UTF-8 characters, you must do one of the
following, or the values extracted by the getParameter method are zeros or are
undefined:
•
Set the enc attribute of the parameter-encoding element to auto (the default)
in the web-apps.xml file. For more information, see “parameter-encoding,” on
page 22.
•
Set the parameterEncoding property to auto (the default) or responseCT in
the contexts.properties file, as in iPlanet Web Server 4.x. For more
information, see “parameterEncoding,” on page 92.
Because the original encoding used to enter data into form fields is lost when the
data is URL-encoded, you must do the following:
•
Always set the response content type when sending a form to a client. This
ensures that the entire form gets safely to the client.
•
When sending form data to a server that uses a different locale than the form
fields, you must tell the server the charset before you call the getParameter
method, as follows:
❍
If the servlet or JSP that generated the form is different than the one
processing the form, use a hidden field in the form (called j_encoding by
default), for example:
<input type="hidden" name="j_encoding" value="US_ASCII">
❍
❍
Set the com.iplanet.server.http.servlet.parameterEncoding
attribute in the request object (see “ServletRequest.setAttribute,” on page
73). The getParameter method uses this attribute to decode the
parameters.
If parameterEncoding=responseCT in contexts.properties and the
same servlet or JSP generates and processes the form, you can set the
response content type. For servlets, explicitly set it as in this example:
res.setContentType("text/plain; charset=Shift_JIS");
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Clarifications for Using Methods
For JSPs, set the response content type using a page directive, for example:
<%@ page contentType="text/html; charset=gb2312"%>
ServletResponse.getOutputStream and
getWriter
public ServletOutputStream getOutputStream() throws
java.io.IOException
Returns a ServletOutputStream suitable for writing binary data in the response.
The servlet container does not encode the binary data. Either this method or
getWriter may be called to write the body, not both.
public java.io.PrintWriter getWriter() throws java.io.IOException
Returns a PrintWriter object that can send character text to the client. The
character encoding used is the one specified in the charset= property of the
setContentType(java.lang.String) method, which must be called before
calling this method for the charset to take effect.
Either this method or getOutputStream may be called to write the body, not both.
Clarification
The specification recommends that when a servlet calls the getWriter method on a
response for which the getOutputStream method has already been called, or the
other way around, the servlet container should throw an
IllegalStateException.
iPlanet Web Server 6.0 doesn’t throw the exception, while ensuring that the writes
to writer and the output stream are ordered. This implementation is more lenient
but preserves correctness and permits scenarios like these:
•
A servlet calls getOutputStream and throws an exception, and a JSP is used
for the exception page. With strict compliance, this fails, because the JSP tries to
call getWriter on the response object.
•
A JSP that calls getWriter includes a servlet that calls getOutputStream.
Chapter
7
API Clarifications
75
Clarifications for Using Methods
RequestDispatcher.forward and include
public void forward(ServletRequest request, ServletResponse
response) throws ServletException, IOException;
Used for forwarding a request from this servlet to another resource on the web
server. This method is useful when one servlet does preliminary processing of a
request and wants to let another object generate the response.
The request object passed to the target object will have its request URL path and
other path parameters adjusted to reflect the target URL path of the target object.
You cannot use this method if a ServletOutputStream object or PrintWriter
object has been obtained from the response. In that case, the method throws an
IllegalStateException.
public void include(ServletRequest request, ServletResponse
response) throws ServletException, IOException;
Used for including the content generated by another server resource in the body of
a response. In essence, this method enables programmatic server-side includes. The
request object passed to the target object reflects the request URL path and path
info of the calling request. The response object only has access to the calling
servlet’s ServletOutputStream object or PrintWriter object.
An included servlet cannot set headers. If the included servlet calls a method that
needs to set headers (such as cookies), it will not work. As a servlet developer, you
must ensure that any methods that might need direct access to headers are
properly resolved. To ensure that a session works correctly, start the session
outside the included servlet, even if you use session tracking.
Clarification
In iPlanet Web Server 6.0, the dispatcher.forward method may or may not throw
an IllegalStateException when either Writer or OutputStream have been
obtained. This behavior follows the 2.2 draft and is needed for JSP error page
handling. It throws the exception only if the actual data has been flushed out and
sent to the client. Otherwise, the data pending in the buffer is simply discarded.
The forward and include methods may throw a ServletException if the target
URI is identified as an unsafe URI (that is, it includes insecure path characters such
as //, /./, /../ and/., /.. (and also ./ for NT) at the end of the URI.
You can control the nesting depth of the RequestDispatcher.forward and
include methods using the requestDispatcherNestDepth parameter in
magnus.conf. For more information, see Appendix A, “Servlet Settings in
magnus.conf and obj.conf.”
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Other Useful Information
Other Useful Information
This section contains information about the following topics:
•
Database Connection Pooling
•
Fetching the Client Certificate
Database Connection Pooling
Database connection pooling enhances the performance of servlet or JSP database
interactions. There are several JDBC 2.0 compatible drivers that support connection
pooling, for example Oracle 8i update and CloudScape 3.0.
Fetching the Client Certificate
When you enable SSL and require client certificate authorization, your servlets
have access to the client certificate as shown in the following example:
if (request.isSecure()) {
java.security.cert.X509Certificate[] certs;
certs = request.getAttribute("javax.servlet.request.X509Certificate");
if (certs != null) {
clientCert = certs[0];
if (clientCert != null) {
// Get the Distinguised Name for the user.
java.security.Principal userDN = clientCert.getSubjectDN();
...
}
}
}
The userDn is the fully qualified Distinguished Name for the user.
Chapter
7
API Clarifications
77
Other Useful Information
78
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Chapter
8
Legacy Servlet and JSP
Configuration
This chapter describes legacy configuration procedures and files, which are
provided for backward compatibility with iPlanet Web Server 4.x, in these sections:
•
The Default Virtual Server
•
Enabling Servlets and JSP
•
Making JSPs Available to Clients
•
Configuring Servlets in the Default Virtual Server
•
Using the User Interface
•
Legacy Configuration Files
•
Legacy Examples
•
Maximizing Legacy Servlet Performance
NOTE
Legacy servlets and JSPs, as described in this chapter, are deprecated.
Creating and deploying web applications as described in Chapter 2,
“Web Applications,” is recommended.
The Default Virtual Server
The default virtual server is the only virtual server in which legacy applications
can be run. When you first install iPlanet Web Server, the default virtual server is
the only virtual server that exists. For more information about how the default
virtual server is defined, see Chapter 8, “Virtual Server Configuration Files,” in the
NSAPI Programmer’s Guide for iPlanet Web Server.
79
Enabling Servlets and JSP
Enabling Servlets and JSP
To enable and disable servlets and JSPs, use the Java>Enable/Disable Servlets/JSP
page in the Server Manager interface.
By default, regardless of whether servlets are enabled or disabled, the file
obj.conf contains objects with names such as servlet, jsp, and ServletByExt.
Do not delete these objects. If you delete them, you can no longer activate servlets
through the Server Manager.
Making JSPs Available to Clients
No special steps are needed to make JSP pages available to clients other than
making sure that servlets and JSP are enabled on the iPlanet Web Server. So long as
JSP is enabled, the iPlanet Web Server treats all files with a .jsp extension as JSPs.
(Do not put JSP files in a registered servlet directory, since the iPlanet Web Server
expects all files in a registered servlet directory to be servlets.)
NOTE
You cannot run JSPs in aliased directories in iPlanet Web Server.
For example, if the document root is server_root/docs, mapping
http://foo.com/myjsp to /some/other/dir instead of
server_root/docs/myjsp does not work.
Configuring Servlets in the Default Virtual Server
There are three ways to make a servlet accessible to clients in the default virtual
server. The second two ways are provided for backward compatibility with iPlanet
Web Server 4.x.
80
•
Include the servlets in web applications and deploy those web applications, as
with any other virtual server. How to do this is described in Chapter 2, “Web
Applications.” This is new in iPlanet Web Server 6.0.
•
Put the servlet class file in one of the directories that has been registered with
the iPlanet Web Server as a servlet directory. For more information, see
“Registering Servlet Directories” on page 81.
•
Define a servlet virtual path for the servlet. In this case, the servlet class can be
located anywhere in the file system or even reside on a remote machine. For
more information, see “Specifying Servlet Virtual Paths” on page 84.
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Configuring Servlets in the Default Virtual Server
In detail, to serve servlets in the default virtual server as in iPlanet Web Server 4.x,
do the following steps:
1.
Configuring Global Servlet Attributes
2.
Registering Servlet Directories
3.
Registering Individual Servlets if Needed
4.
Specifying Servlet Virtual Paths if Desired
5.
Specifying Servlet Contexts if Desired
Configuring Global Servlet Attributes
You can specify the following optional servlet attributes:
•
Startup Servlets -- servlets to be loaded when the iPlanet Web Server starts up.
•
Session Manager -- the session manager for servlets. For more information
about the session manager, see Chapter 6, “Session Managers.”
•
Session Manager Args -- the session manager arguments for the servlet engine.
For more information about the session manager, see Chapter 6, “Session
Managers.”
•
Reload Interval -- the time period that the server waits before re-loading
servlets and JSPs if they have changed on the server. The default value is 5
seconds.
You can set these attributes interactively in the Legacy Servlets>Configure Global
Servlet Attributes page in the Server Manager interface. Alternatively, you can edit
the configuration files servlets.properties and contexts.properties in the
server’s config directory.
Registering Servlet Directories
One of the ways to make a servlet accessible to clients is to put it into a directory
that is registered with the iPlanet Web Server as a servlet directory. Servlets in
registered servlet directories are dynamically loaded when needed. The server
monitors the servlet files and automatically reloads them on the fly as they change.
You can register any number of servlet directories for iPlanet Web Server. Initially,
iPlanet Web Server has a single servlet directory, which is
server_root/docs/servlet/.
Chapter
8
Legacy Servlet and JSP Configuration
81
Configuring Servlets in the Default Virtual Server
For example, if the SimpleServlet.class servlet is in the servlet subdirectory of
the server’s document root directory (the default servlet directory), you can invoke
the servlet by pointing the web browser to:
http://your_server/servlet/SimpleServlet
iPlanet Web Server expects all files in a registered servlet directory to be servlets.
The server treats any files in that directory that have the .class extension as
servlets. The iPlanet Web Server does not correctly serve other files, such as HTML
files or JSPs, that reside in that directory.
The server can have multiple servlet directories. You can map servlet directories to
virtual directories if desired. For example, you could specify that
http://poppy.my_domain.com/products/ invokes servlets in the directory
server_root/docs/january/products/servlets/.
To register servlet directories and to specify their URL prefixes, use the Legacy
Servlets>Servlet Directory page in the Server Manager interface.
Alternatively, you can register servlet directories by adding appropriate
NameTrans directives to the default object in the file obj.conf, such as:
NameTrans fn="pfx2dir" from="/products"
dir="d:/netscape/server4/docs/january/products/servlets/"
name="ServletByExt"
You can invoke a servlet in a subdirectory of a registered servlet directory if you
include a package directive in the servlet code that corresponds to the path from
the registered servlet directory. For example, suppose the servlet is in the following
location, and that server_root/docs/servlet/ is a registered servlet directory:
server_root/docs/servlet/HelloWorld/HelloWorldServlet.class
Include the following package directive as the first line in the Java source file:
package HelloWorld;
You can then invoke the servlet by pointing the web browser to:
http://your_server/servlet/HelloWorld.HelloWorldServlet
For information about reloading packaged servlets, see
“isModifiedCheckAggressive,” on page 92.
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Configuring Servlets in the Default Virtual Server
Registering Individual Servlets
The iPlanet Web Server treats any file in a registered servlet directory as a servlet.
There is no need to register individual servlets that reside in these directories
unless any of the following criteria apply:
•
The servlet takes input parameters that are not passed through the request
URL.
•
You want to set up additional virtual URLs for the servlet.
•
Your servlets are packaged or in a .jar file. The server does not search .class
or .jar files for packaged servlets.
If any of these conditions is true, register the individual servlet by using the Legacy
Servlets>Configure Servlet Attributes page in the Server Manager interface.
Alternatively, you can edit the file servlets.properties to add an entry for the
servlet.
When registering an individual servlet, specify the following attributes:
•
Servlet Name -- The iPlanet Web Server uses this value as a servlet identifier to
internally identify the servlet. (This identifier is not part of the URL that is used
to invoke the servlet, unless by coincidence the identifier is the same as the
class code name.)
•
Servlet Code (class name) -- the name of the class file. You do not need to
specify the .class extension.
•
Servlet Classpath -- This is the absolute pathname or URL to the directory or
zip/jar file containing the servlet. The classpath can point anywhere in the file
system. The servlet classpath may contain a directory, a .jar or .zip file, or a
URL to a directory. (You cannot specify a URL as a classpath for a zip or jar
file.)
If the servlet classpath is not a registered servlet directory, you must
additionally provide a servlet virtual path for it (as discussed in “Specifying
Servlet Virtual Paths,” on page 84) to make the servlet accessible to clients.
iPlanet Web Server supports the specification of multiple directories, jars, zips,
and URLs in the servlet classpath.
•
Servlet Args -- a comma delimited list of additional arguments for the servlet if
required.
The following code shows an example of the configuration information for the
same servlet in servlets.properties:
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Configuring Servlets in the Default Virtual Server
servlet.BuyNowServlet.classpath=D:/Netscape/server4/docs/servlet
/buy;D:/Netscape/server4/docs/myclasses
servlet.BuyNowServlet.code=BuyNow1A
servlet.BuyNowServlet.initArgs=arg1=45,arg2=online,arg3="quick
shopping
Note that you can specify multiple values as the servlet classpath if needed.
Specifying Servlet Virtual Paths
If you register a servlet individually instead of putting it in a servlet directory, you
must define a servlet virtual path for it. For example, you could specify that the
URL
http://poppy.my_domain.com/plans/plan1
invokes the servlet defined in the directory
server_root/docs/plans/releaseA/planP2Version1A.class
You can set up servlet virtual paths for servlets that reside anywhere in the file
system, in or out of a registered servlet directory.
To specify a servlet virtual path, use the Legacy Servlets>Configure Servlet Virtual
Path Translation page in the Server Manager interface. In this page, specify the
virtual path name and the servlet name. You can alternatively manually edit the
rules.properties configuration file to add a servlet virtual path. Only servlets
for which a virtual path has been set up can use initial arguments.
Before using a servlet virtual path, a servlet identifier (or servlet name) must be
added for the servlet in the Legacy Servlets>Configure Servlet Attributes page of
the interface (or in the servlets.properties configuration file).
Virtual Servlet Path Example
This example shows how to specify that the logical URL
http://poppy.my_domain.com/plans/plan1
invokes the servlet defined in
server_root/docs/plans/releaseA/planP2Version1A.class.
1.
84
Specify the servlet identifier, class file, and class path.
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Configuring Servlets in the Default Virtual Server
In the Legacy Servlets>Configure Servlet Attributes page in the interface, do
the following:
❍
❍
❍
❍
In the Servlet Name field, enter an identifier for the servlet, such as plan1A.
(Notice that this is not necessarily the same as the class file name).
In the Servlet Code field, enter the name of the class file, which is
planP2Version1A. Don’t specify any directories. The .class extension is
not required.
In the Servlet Classpath field, enter the absolute path name for the
directory, jar or zip file where the servlet class file resides, or enter a URL
for a directory. In this example, you would enter
server_root/docs/servlet/plans/releaseA. (For example:
D:/netscape/server4/docs/servlet/plans/releaseA.)
In the Servlet Args field, enter the additional arguments that the servlet
needs, if any. (This example does not use extra arguments.)
Save the changes.
To make this change programmatically, add the following lines to the
configuration file servlets.properties:
servlet.plan1A.classpath=D:/Netscape/server4/docs/servlet/pla
ns/releaseA/
servlet.plan1A.code=planP2Version1A
2.
Specify the virtual path for the servlet.
In the Legacy Servlets>Configure Servlet Virtual Path Translations page, do
the following:
❍
❍
In the Virtual Path field, enter the virtual path name. Note that the server
name is implied as a prefix, so in this case you would only need to enter
/plans/plan1 to specify the virtual path
http://poppy.mcom.com/plans/plan1.
In the Servlet field, enter the identifier for the servlet that is invoked by this
virtual path. This is the servlet identifier that you specified in the
Configure Servlet Attributes page, which in this case is plan1A.
Save the changes.
To do this programmatically, add the following line to rules.properties:
Chapter
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Using the User Interface
/plans/plan1=plan1A
After this virtual servlet path has been established, if a client sends a request to
the server for the URL http://poppy.my_domain.com/plans/plan1, the
server sends back the results of invoking the servlet in
server_root/docs/servlet/plans/releaseA/plan2PVersion1A.class.
Specifying Servlet Contexts
Contexts allow multiple servlets to exchange data and access each other’s fields.
Contexts are useful for defining virtual servers or for code isolation. You define
contexts in the servlets.properties and contexts.properties files.
Using the User Interface
For information about using the user interface to specify settings for legacy servlets
and JSPs, see the following topics in the online help.
This page is located in the Web Server Administration Server on the Global
Settings tab.
•
The Configure JRE/JDK Paths Page
These pages are located in the Server Manager on the Java tab.
•
The Enable/Disable Servlets/JSP Page
•
The Configure JVM Attributes Page
•
The Delete Version Files Page
These pages are located in the Server Manager on the Legacy Servlets tab.
86
•
The Configure Global Servlet Attributes Page
•
The Configure Servlet Attributes Page
•
The Configure Servlet Virtual Path Translation Page
•
The Configure Servlet Directory Page
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Legacy Configuration Files
Legacy Configuration Files
This section discusses the purpose and use of the following files:
•
servlets.properties
•
rules.properties
•
contexts.properties
All of these files reside in the directory server_id/config.
NOTE
In iPlanet Web Server 6.0, a web-apps.xml file exists for each
virtual server, allowing you to configure separate web applications
for each virtual server. The servlets.properties,
rules.properties, and contexts.properties files apply only to
the default virtual server for the server instance; they exist for
backward compatibility. Using the web-apps.xml file for all web
application configuration is recommended. For more information
about the web-apps.xml file, see Chapter 2, “Web Applications.”
servlets.properties
The servlets.properties file defines global servlet settings and the list of
servlets in the system, for the default virtual server only.
An example of a global servlet setting is which servlet to run when the iPlanet Web
Server starts up. The servlets.properties file also specifies configuration
information for individual servlets. Configuration information includes the class
name, the classpath, and any input arguments required by the servlet.
If you want to specify a virtual path translation for a servlet, the servlet must be
configured in the servlets.properties file.
You can specify configuration information for servlets either by using the Legacy
Servlets>Configure Servlet Attributes page in the Server Manager interface or by
editing servlets.properties directly. Whenever you make a change in the
Legacy Servlets>Configure Servlet Attributes page in the Server Manager interface,
the system automatically updates servlets.properties.
When specifying attributes for a servlet, you specify a name parameter for the
servlet. This name does not have to be the name of the class file for the servlet; it is
an internal identifier for the servlet. You specify the name of the class file as the
value of the code parameter.
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Legacy Configuration Files
Here is a sample servlets.properties file:
# Servlets Properties
# servlets to be loaded at startup
servlets.startup= hello
# the default document root,
# needed so ServletContext.getRealPath will work
servlets.config.docRoot=d:/Netscape/Server4/docs
# tracker servlet
servlet.tracker.code=MyTrackerServlet
servlet.tracker.classpath=d:/Netscape/Server4/docs/servlet
# demo1 servlet
servlet.demo1.code=Demo1Servlet
servlet.demo1.classpath=d:/Netscape/Server4/docs/demos
servlet.demo1.initArgs=a1=0,b1=3456
servlet.demo1.context=context1
rules.properties
The rules.properties file defines servlet virtual path translations, for the default
virtual server only. For example, you could set up a mapping so that the URL
pointing to /mytest2 invokes the servlet named demo1 in the
servlets.properties file. You can specify virtual paths for your servlets either
by setting parameters in the Legacy Servlets>Configure Servlet Virtual Path
Translation page of the Server Manager interface or by specifying the paths in the
rules.properties file.
Note that the name associated with the servlet in servlets.properties is used in
the file rules.properties -- the class name of the servlet does not show up in
rules.properties. For example, the following lines in servlets.properties
associate the servlet name demo1 with the servlet class file Demo1Servlet.class in
the directory d:/Netscape/Server4/docs/demos.
# in servlets.properties
# demo1 servlet
servlet.demo1.code=Demo1Servlet
servlet.demo1.classpath=d:/Netscape/Server4/docs/demos
The following line in rules.properties defines a servlet virtual path translation
such that the URL http://server_id/mytest2 invokes the servlet at
d:/Netscape/Server4/docs/demos/Demo1Servlet.class.
/mytest2=demo1
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Legacy Configuration Files
Here is an example of rules.properties.
# Servlet rules properties
#
# This file specifies the translation rules for invoking servlets.
# The syntax is:
#
<virtual-path>=<servlet-name>
#
or
#
@regular_expression=<servlet-name> (use double back-slashes)
#
# where <virtual-path> is the virtual path used to invoke the servlet,
# and <servlet-name> is the name of the servlet. Surrounding white space
# is ignored. The ordering of the rules is not important, as the longest
# match will always be used first. Use of regular expression can lead to
# a heavy peformance penalty
#
################################# rules ################################
/mytest1=tracker
/mytest2=demo1
Using Regular Expressions in rules.properties
iPlanet Web Server supports regular expressions in the rules.properties file to
run a given servlet when the incoming URL matches with a regular expression.
However, the example given in the file header is incorrect:
# Example:
#
# /simple=SimpleServlet\n
# @.*\\.foo=wasp
The \\ characters are supposed to escape the (.) extension. The intent is to run the
example wasp servlet whenever there is a request for URLs such as /my/xxx.foo.
However, iPlanet Web Server replaces / or \ characters with /, subsequently
changing the whole semantics. To get around this, specify the regular expression
without the / or \ characters:
@.*[.]foo$=wasp
For another way to direct files of a specific type to a specific servlet, see the
description of the servlet-mapping element in the web.xml file, which is
described in the Servlet 2.2 API specification:
http://java.sun.com/products/servlet/index.html
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89
Legacy Configuration Files
For a way to direct files of a specific type to a specific servlet in the obj.conf file,
see “Init Directives in magnus.conf,” on page 95.
contexts.properties
The contexts.properties file defines contexts, which allow multiple servlets to
exchange data and access each other’s fields, for the default virtual server only.
Contexts are useful for defining virtual servers or for code isolation. If no contexts
are defined, the default global context is used for all servlets.
NOTE
All JSPs belong to the default global context. You cannot define
custom contexts for JSPs. However, you can change the properties
of the global context to affect JSPs.
If the context for a servlet is not defined, the servlet belongs to the global context.
You can use the same servlet in multiple contexts.
Only the name of a context is required. Any other unspecified properties are
inherited from the global context. You can also change the properties of the global
context. The comments in the contexts.properties file list the default property
values of the global context.
Here is an example of contexts.properties.
# @(#)contexts.properties (autogenerated)
#
# Contexts Properties:
#
# context.<context_name>.sessionmgr=session manager (some session managers
#
(like MMapSessionManager) can only be instatiated once within the
#
#
#
#
#
#
#
#
#
#
#
#
#
90
server
context.<context_name>.sessionmgr.initArgs=list of (name, value) pairs which
will represent parameters specific to the session manager
context.<context_name>.initArgs=list of (name, value) pairs which will be added
to this context’s attributes
context.<context_name>.respondCookieVersion=(cookie version) tells the server
whether to respond with specific cookie version
context.<context_name>.sessionExpireOnClose(true|false) tells the server to
mark session cookies as directed to expire when the user quits
the browser
context.<context_name>.tempDir=path (forward slashes only) - sets up Servlet API
2.2 property for the temporary directory
context.<context_name>.reloadInterval=seconds - time interval within which the
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Legacy Configuration Files
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
server checks for jsp and servlet files being modified (global
context only)
context.<context_name>.bufferSize=bytes - initial http output stream buffer size
context.<context_name>.docRoot=path (forward slashes only) - this context
document root when not specified - web server’s document root
will be used (default)
context.<context_name>.inputStreamLengthCheck=(true|false) - makes
ServletInputStream stop reading data when Content-Length bytes
are read
context.<context_name>.outputStreamFlushTimer=(seconds|0) - forces the stream
to flush the data if certain time elapsed since the last flush;
0 - ignore it
context.<context_name>.uri=contex_uri_base - additional URI prefix which
servces as a context base
context.<context_name>.authdb=name - authentication database
context.<context_name>.classpath=name - global classpath for this context
context.<context_name>.signleClassLoader=(true|false) - tells the servlet
engine whether to use a single class loader for all servlets in
the context
context.<context_name>.serverName=name - server instance name
context.<context_name>.contentTypeIgnoreFromSSI=(true|false) - ignore
setContentType when invoked from SSI
context.<context_name>.parameterEncoding=(utf8,none,auto) - advises the web
server on how to decode parameters from forms
context.<context_name>.isModifiedCheckAggressive=(true|false) - determines
whether to be aggressively checking dependencies for the servlet
loader to reload modified servlets
<context_name>="global" is reserved for the global context. Every new context
will inherit initial settings of the global context
Context properties:
context.global.sessionmgr=com.netscape.server.http.session.SimpleSessionManager
context.global.sessionmgr.initArgs=
context.global.initArgs=initial=0
context.global.respondCookieVersion=0
context.global.tempDir=/tmp
context.global.reloadInterval=5
context.global.bufferSize=4096
context.global.docRoot=/foo/bar
context.global.inputStreamLengthCheck=true
context.global.outputStreamFlushTimer=0
context.global.uri=/
context.global.authdb=default
context.global.classpath=
context.global.singleClassLoader=false
context.global.contentTypeIgnoreFromSSI=true
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91
Legacy Configuration Files
# context.global.parameterEncoding=utf8
# context.global.isModifiedCheckAggressive=false
#
################################# Contexts #############################
context.global.initArgs=docRoot=C:/iPlanet/Servers
context.context1.name=context1
The following sections explain a few of the context properties in more detail.
isModifiedCheckAggressive
When you modify a packaged servlet, the new version is not reloaded
automatically unless you have done one of the following:
•
Set the isModifiedCheckAggressive property to true, for example:
context.global.isModifiedCheckAggressive=true
•
Used the .class extension when invoking the servlet, for example:
http://your_server/servlet/HelloWorld.HelloWorldServlet.class
parameterEncoding
The context.global.parameterEncoding property allows you determine the
character encoding of servlet parameters. It has the following options:
none
Uses the system default encoding. Set this option if the encoding of the
servlet parameter data is the same as the system default encoding.
auto
(Default) Tries to figure out the proper encoding from, in order, 1) the
charset if it is set in the Content-Type header, 2) the
parameterEncoding attribute (see “ServletRequest.setAttribute,”
on page 73), then 3) a hidden form field, such as j_encoding.
Otherwise, the system default encoding is used. Set this option to
prevent misinterpretation of non-ASCII characters in servlet
parameters.
When this property is set to auto, the server has to convert native
characters into a java byte array before transforming them into the
requested encoding. Therefore, performance is slightly better for none
or a specific encoding.
any supported
java character
encoding
A specific encoding, such as utf8 or Shift_JIS. Set this option if you
know the encoding that servlet parameters use. A complete list is
available here:
http://java.sun.com/j2se/1.3/docs/guide/intl/encodin
g.doc.html
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Legacy Examples
responseCT
Tries to figure out the proper encoding from the response content type
if it is available. Otherwise, the system default encoding is used.
If a servlet uses the ServletRequest.getParameter method to retrieve values in
form fields having non-UTF-8 characters, the parameterEncoding property must
be set to auto (the default) or responseCT in the contexts.properties file.
Otherwise, the values extracted by the getParameter method are zeros or are
undefined. For more information see “ServletRequest.getParameter,” on page 74.
The parameterEncoding property setting applies to how a servlet processes
parameters after the iPlanet Web Server receives a request. The URI that is sent to
the server must consist of only the standard ASCII set, especially if the request
method is GET. All other characters must be encoded.
For example, to encode a backslash, you would replace the backslash with a %
followed by the hexadecimal number corresponding to the backslash in the ASCII
character set, 5c. Therefore, vw\xyz becomes vw%5cxyz. For more information
about characters that must be encoded, see “parameter-encoding,” on page 22.
singleClassLoader
By default, the singleClassLoader property is false, which means that each
servlet is loaded in a different class loader, even if the servlets share a context. This
makes it difficult for two servlets to access each other’s static class members. To
load all servlets within a context in the same class loader, set the
singleClassLoader property to true.
Servlet reloading (which occurs when .class or .jsp files are changed) does not
work when singleClassLoader=true.
If singleClassLoader=true, RequestDispatcher.forward calls to JSPs do not
work unless you add the ClassCache directory to the context.global.classpath
line in contexts.properties. For example:
context.global.singleClassLoader=true
context.global.classpath=server_root/https-server_id/ClassCache
Legacy Examples
iPlanet Web Server 6.0 comes with a set of legacy example servlets and JSP files.
You can find them at the following location:
server_root/plugins/servlets/examples/legacy
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93
Maximizing Legacy Servlet Performance
The legacy subdirectory contains the following directories:
•
beans.10 -- Contains example Java Bean files for JSP 1.x.
•
jsp.10 -- Contains subdirectories that each contain an example for JSP 1.x.
•
jsp.10/hangman -- Contains a JSP application that was an SSJS application in
iPlanet Web Server 4.x. For more information about converting SSJS
applications to JSPs, see Appendix B, “Converting SSJS Applications.”
•
make -- Contains example makefiles for servlets. These are common makefiles
containing rules that are included by all other makefiles.
•
servlets -- Contains subdirectories that each contain Java source files and
makefiles for servlet examples.
•
tools -- Contains the SDKTools.jar file and other utility files.
Maximizing Legacy Servlet Performance
Consider the following guidelines for improving servlet performance:
•
If you edit your obj.conf file manually, make sure that the servlet NameTrans
(NameTrans fn="NSServletNameTrans" name="servlet") is always the first
NameTrans directive.
This directive uses a highly optimized URI cache for loaded servlets and
returns REQ_PROCEED if the match is found, thus eliminating the need of other
NameTrans directives to be executed.
•
94
In the default virtual server, servlets defined individually (via the Configure
Servlet Attributes page or rules.properties and servlets.properties) are
slightly faster than dynamically loaded servlets (in servlet directories).
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Appendix
A
Servlet Settings in magnus.conf and
obj.conf
The iPlanet Web Server 6.0 Administration Server automatically modifies the
magnus.conf and obj.conf files to load the servlet engine if servlets are enabled.
Whenever you make changes to servlet settings by using the Server Manager
interface, the system automatically updates these files appropriately.
However, in case you are interested in the settings that affect servlets, this
appendix describes them in the following sections:
•
Init Directives in magnus.conf
•
Objects in obj.conf
•
Directives for Registered Servlet Directories
•
JSP Directives
Init Directives in magnus.conf
The following directives in the Init section of magnus.conf load and initialize the
servlet engine to enable servlets (for Windows NT):
Init fn="load-modules"
shlib="server_root/bin/https/bin/NSServletPlugin.dll"
funcs="NSServletEarlyInit,NSServletLateInit,NSServletNameTrans,
NSServletService" shlib_flags="(global|now)"
Init fn="NSServletEarlyInit" EarlyInit=yes
Init fn="NSServletLateInit" LateInit=yes
95
Objects in obj.conf
for Unix, the directives are the same except for the following parameter:
shlib="server_root/bin/https/lib/libNSServletPlugin.so"
NSServletEarlyInit takes an optional parameter, cache_dir, which specifies the
location of a temporary cache directory for JSP classes. By default, the directory is
named ClassCache and goes under your server root directory.
NSServletLateInit takes the following optional parameters:
CatchSignals
Specifies whether or not Java thread dumps are
logged. The value is yes or no.
requestDispatcherNestDepth
Controls the nesting depth of the
RequestDispatcher.forward and include
methods. The default depth is 10. This parameter
also affects nesting levels of JSP forward and
include invocations. You cannot assign an
arbitrary value for this depth unless the
StackSize magnus.conf directive is set to an
appropriate value. Setting this parameter to an
arbitrarily high value may result in stack overflow
and a server crash.
Objects in obj.conf
NOTE
The information in this section applies to legacy (iPlanet Web Server
4.x) servlets and is deprecated.
NSServletService takes two optional parameters, servlet="servlet_name" and
context="context_name". These parameters allow you to define objects in
obj.conf that generate responses for specific servlets or contexts. You can use one
or both parameters in a directive. The servlet or context must be defined in the
servlets.properties or contexts.properties file. You can define an object
that pertains to a particular servlet, a particular servlet context, or both. For
example, you can direct files of a specific type (in this case, *.foo) to a specific
servlet (in this case, the wasp servlet):
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Objects in obj.conf
<Object name="default">
NameTrans fn=assign-name name=foo from=*.foo
...other directives...
</Object>
<Object name="foo">
ObjectType fn=force-type type=magnus-internal/servlet
Service fn="NSServletService" servlet="wasp"
</Object>
For another way to direct files of a specific type to a specific servlet, see the
description of the servlet-mapping element in the web.xml file, which is
described in the Servlet 2.2 API specification:
http://java.sun.com/products/servlet/index.html
For a way to direct files of a specific type to a specific servlet as in iPlanet Web
Server 4.x, see “Using Regular Expressions in rules.properties,” on page 89.
For an example of the basic use of NSServletService, see the discussion of
Service examples in Chapter 2, “Syntax and Use of Obj.conf” in the NSAPI
Programmer’s Guide for iPlanet Web Server.
When servlets are enabled, the following directive appears in the default object:
NameTrans fn="NSServletNameTrans" name="servlet"
This directive is used for servlet virtual path translations and for the URI cache. Do
not delete this line.
Also, obj.conf always has the following object, which you should not delete:
<Object name="servlet">
ObjectType fn=force-type type=text/html
Service fn="NSServletService"
</Object>
If you delete this object, you can no longer use the Server Manager interface to
enable servlets and modify servlet settings.
For more information, see the NSAPI Programmer’s Guide for iPlanet Web Server.
Appendix
A
Servlet Settings in magnus.conf and obj.conf
97
Directives for Registered Servlet Directories
Directives for Registered Servlet Directories
NOTE
The information in this section applies to legacy (iPlanet Web Server
4.x) servlets and is deprecated.
For each registered servlet directory, the default object in obj.conf has a
NameTrans directive that assigns the name ServletByExt to all requests to access
that directory. For example:
NameTrans fn="pfx2dir" from="/servlet"
dir="D:/Netscape/Server4/docs/servlet" name="ServletByExt"
A separate object named ServletByExt has instructions for processing requests for
servlets:
<Object name="ServletByExt">
ObjectType fn="force-type" type="magnus-internal/servlet"
Service type="magnus-internal/servlet" fn="NSServletService"
</Object>
Do not delete this object, even if no servlet directories are currently registered. If
this object is deleted, you can no longer use the Server Manager interface to register
servlet directories.
JSP Directives
The following line in mime.types sets the type for files with the extension .jsp:
type=magnus-internal/jsp exts=jsp
The following directive in obj.conf handles the processing of requests for files of
type magnus-internal/jsp (that is, JSP files). It is necessary for legacy JSPs only.
Service fn="NSServletService" type="magnus-internal/jsp"
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Appendix
B
Converting SSJS Applications
This appendix contains information about converting Server-Side JavaScript
applications to JSPs. It has the following sections:
•
Differences Between JavaScript and Java
•
JavaScript to Java Class Conversions
•
Conversion Steps
•
Example Conversion
Differences Between JavaScript and Java
Before you can convert SSJS applications to JSPs, you must understand the
differences between JavaScript and Java. JavaScript and Java are similar in some
ways but fundamentally different in others.
JavaScript lacks Java’s static typing and strong type checking. JavaScript supports
a runtime system based on a small number of data types representing numeric,
Boolean, and string values. Java has a compile-time system of classes built by
declarations.
JavaScript also supports functions without any special declarative requirements.
Functions can be properties of objects, executing as loosely typed methods. In Java,
methods are defined in and belong to classes, and they are strongly typed.
JavaScript is a very free-form language compared to Java. In Java, you must declare
all variables, classes, and methods. You must declare methods as public, private, or
protected. Variables, parameters, and method return types are explicitly typed.
99
Differences Between JavaScript and Java
Java is a class-based programming language designed for fast execution and type
safety. Type safety means, for instance, that you can’t cast a Java integer into an
object reference or access private memory by corrupting Java bytecodes. Java’s
class-based model means that programs consist exclusively of classes and their
methods. Java’s class inheritance and strong typing generally require tightly
coupled object hierarchies. These requirements make Java programming more
complex than JavaScript authoring.
Table B-1
100
JavaScript and Java compared
JavaScript
Java
Interpreted (not compiled) by client.
Compiled bytecodes downloaded from
server, executed on client.
A scripting language that supports objects.
An object-oriented language.
No distinction between types of objects.
Inheritance is through the prototype
mechanism, and properties and functions
can be added to any object dynamically.
Objects are divided into classes and
instances with all inheritance through the
class hierarchy. Classes and instances
cannot have properties or methods added
dynamically.
Functions may be inside classes but do not
have to be.
Every method must be inside a class.
Code integrated with, and embedded in,
HTML.
Code distinct from HTML, although JSPs
can contain HTML tags.
Loosely cast: variable and function types
not declared (dynamic typing).
Tightly cast: variable and method types
must be declared (static typing).
Cannot automatically write to hard disk.
Cannot automatically write to hard disk.
Semicolons at the ends of statements are
optional.
All statements must end with a semicolon
(;).
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
JavaScript to Java Class Conversions
JavaScript to Java Class Conversions
The objects used in an SSJS application must be converted to classes in Java. Table
B-2 can help you convert these objects.
Table B-2
JavaScript and Java basic classes
SSJS Class
Java Class
Comments
Client
Session
A Java session is not as automatic as an
SSJS client.
Project
Context
Request
Request
Server
System or Context
Methods are split between two Java
classes.
SSJS includes a special library to handle database connectivity. Since JSPs are Java,
all database connectivity is handled through JDBC. JDBC database drivers are
available directly from the database vendors. It is a good idea to use pure Java
(type 4) drivers whenever they are available. Table B-3 lists the database
connectivity classes.
Table B-3
JavaScript and Java database classes
SSJS Class
Java Class
Comments
Connection
Connection
Cursor
ResultSet
There is no Cursor object; you can use
methods in the ResultSet class to
move the cursor.
DbPool
PooledConnection
This class is in the JDBC optional
package.
Stproc
CallableStatement
ResultSet
ResultSet
Appendix
B
Converting SSJS Applications
101
Conversion Steps
Conversion Steps
When converting applications, follow these steps:
1.
Go over the structure of the application to see if there are helper classes that
provide functionality between pages. Convert these helper classes first so that
they are ready to use in your pages. (The hangman example contains a helper
class, called hangman.js in the original JavaScript application and called
JavaHangManUtil.java in the JSP application shipped with iPlanet Web
Server 6.0.) Write helpers as .java files and compile them into .class files
before using them.
2.
Define the methods within classes. The methods (functions in JavaScript) must
declare what they return and who can access them. For example, in JavaScript
you can write:
function InitAnswer(str) { function_code }
In Java, the same method must be declared as follows:
public static String InitAnswer(String str) { method_code }
This method passes in a String and returns a String. The public keyword
means that any other class can call this method. The static keyword means that
the virtual machine can run this method without creating an object of the class
containing the method.
3.
Convert the client object of the application to a session bean. In Server-Side
JavaScript, data is easier to use in the client object. In a Java Session object, the
programmer must get data from the session and then put it back in if there are
changes. This work can be done in a wrapper bean. The bean handling
functionality of JSPs is very strong. You can specify the scope to be session
and it is saved in the session automatically.
4.
Convert the HTML files to JSP files. This mainly consists of finding the
<SERVER> and </SERVER> tags and replacing them with the <% and %> JSP tags.
Then go through and change the syntax to correct JSP or Java syntax.
5.
It is sometimes necessary to add special lines to the file. For example, the line
<%@ page import="HangManUtil,HangBean" %>
imports helper classes, and the line
<jsp:useBean id="client" scope="session" class="HangBean"/>
uses a session bean.
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Example Conversion
Example Conversion
The hangman example, which was a Server-Side JavaScript example in the 4.1
version of iPlanet Web Server, have been converted to a JavaServer Pages example
in the 6.0 version. You can find the converted example under the following
directory:
server_root/plugins/servlets/examples/legacy/jsp.10/hangman
Appendix
B
Converting SSJS Applications
103
Example Conversion
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Appendix
C
JVM Configuration
The Java Virtual Machine (JVM) works by default without any additional
configuration if properly set up.
However, if you need to specify settings for the JVM, such as additional classpath
information, you can configure the JVM properties for iPlanet Web Server via the
Administrator interface. You can add as many other properties as you want to (up
to 64).
NOTE
A few attributes on the Configure JVM Attributes page on the Java
tab show as “Default.” Since you can use different JVMs, these
default values are unknown. You cannot query a JVM to find out
the actual default values; instead, refer to your JVM
documentation. For example, for Sun’s JVM, if you choose Yes for
the JIT Compiler option, it shows as “Default” because JIT is
enabled in the JVM by default. However, if you choose No for the
JIT compiler, an explicit entry, jvm.compiler=NONE, is added to the
jvm12.conf file.
For information about JVM, see The Java Virtual Machine Specification from Sun at:
http://java.sun.com/docs/books/vmspec/2nd-edition/html/VMSpecTOC.doc.html
The jvm12.conf File
You can also configure JVM parameters by editing the jvm12.conf configuration
file, which resides under the server’s config directory.
For example, to disable JIT, you can add the following line to jvm12.conf:
java.compiler=NONE
105
Using JVM Environment Variables
Here is an example jvm12.conf file. The jvm.classpath value must be all on one
line in the actual file.
[JVMConfig]
#jvm.minHeapSize=1048576
#jvm.maxHeapSize=16777216
#jvm.enableClassGC=0
#jvm.verboseMode=1
#jvm.enableDebug=1
#jvm.printErrors=0
#jvm.option=-Xrunoii
#jvm.profiler=optimizeit
#jvm.disableThreadRecycling=0
#jvm.serializeAttach=0
#jvm.stickyAttach=0
#jvm.trace=5
#java.compiler=NONE
#OPTITDIR=D:/App/IntuitiveSystems/OptimizeIt30D
#jvm.serializeFirstRequest=0
#jvm.include.CLASSPATH=1
#nes.jsp.forkjavac=0
#nes.jsp.enabledebug=1
jvm.classpath=/usr/java/tools.jar
Generally you should use plain property options (like name=value) for the JDK1.2
configuration and jvm.option=options for JVM-vendor dependent configurations.
There can be multiple occurrences of jvm.option parameters.
A list of debugging options that you can include in the jvm12.conf file if the JPDA
is installed is available here:
http://java.sun.com/products/jpda/doc/conninv.html#Invocation
For more information about debugging servlets and JSPs and the jvm12.conf
parameters required for debugging, see Chapter 5, “Debugging Servlets and JSPs.”
Using JVM Environment Variables
If you define JVM environment variables using the jvm.option setting in the
jvm12.conf file or the Administration Server, servlets do not recognize them. Just
use the plain name=value format for environment variables.
When you are running a stand-alone command line java program, use the
following option to pass system properties into the java program:
java -Dorg.omg.CORBA.ORBClass=com.inprise.vbroker.orb.ORB myprogram
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
jvm12.conf Parameter Reference
In the myprogram.java file, the following line retrieves the system property set
above:
System.out.println("org.omg.CORBA.ORBClass="+System.getProperty("org.omg.CORBA.ORBClass"));
If you want to do the same thing for servlets in iPlanet Web Server, you need to put
the following line in the jvm12.conf file:
org.omg.CORBA.ORBClass=com.inprise.vbroker.orb.ORB
Do not use jvm.option settings such as the following:
jvm.option=-Dorg.omg.CORBA.ORBClass=com.inprise.vbroker.orb.ORB
or
jvm.option=org.omg.CORBA.ORBClass=com.inprise.vbroker.orb.ORB
In the servlet or JSP, you can use the following line to retrieve the system property
set above:
out.println("org.omg.CORBA.ORBClass="+System.getProperty("org.omg.CORBA.ORBClass"));
jvm12.conf Parameter Reference
The JVM parameters you can set in the jvm12.conf file are listed in Table C-1.
Table C-1
jvm12.conf settings
Setting
Allowed Values
jvm.minHeapSize
Default Value
Description
1048576
(1 MB)
The minimum heap size
allocated to Java.
For Solaris, change this value to
3145278 (3 MB). For HPUX,
change this value to 4194304
(4 MB). For all other operating
systems, 1 MB is ideal.
jvm.maxHeapSize
jvm.enableClassGC
0 (off), 1 (on)
16777216
(16 MB)
The maximum heap size
allocated to Java.
0
Enables or disables class
garbage collection.
Use instead of -Xnoclassgc.
Appendix
C
JVM Configuration
107
jvm12.conf Parameter Reference
Table C-1
jvm12.conf settings
Setting
Allowed Values
Default Value
Description
jvm.verboseMode
0 (off), 1 (on)
0
Enables or disables JVM verbose
mode. If on, the JVM logs a
commentary on what it is doing,
such as loading classes. The
commentary appears in the
error log.
jvm.enableDebug
0 (off), 1 (on)
0
Enables or disables JVM remote
debugging.
Use instead of -Xdebug.
For more information about
remote debugging, see Chapter
5, “Debugging Servlets and
JSPs.”
jvm.printErrors
0 (off), 1 (logs
to log file), 2
(logs to
stderr)
0
Enables or disables reporting of
errors through vfprintf.
Allows you to set vendor JVM
options.
jvm.option
The following options are
ignored, because there are
equivalents to these settings: -D,
-Xnoclassgc, -Xdebug,
-Xms, -Xmx, -verbose
Specifies the profiler. If you use
the optimizeit profiler from
Intuitive Systems, you must also
set the OPTIDIR setting.
jvm.profiler
For more information about this
optimizer, see Appendix D,
“Remote Servlet Profiling.”
jvm.disableThreadRecycling
108
0 (off), 1 (on)
0
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Enables or disables thread
recycling. If on, the server
always creates a global scope
thread to execute servlets.
Otherwise a global scope thread
is created only when the request
handling thread is not in the
global scope.
jvm12.conf Parameter Reference
Table C-1
jvm12.conf settings
Setting
Allowed Values
Default Value
Description
jvm.serializeAttach
0 (off), 1 (on)
0
If on, threads that attach to the
JVM are serialized. By default (if
off), threads can attach to the
JVM in parallel.
jvm.stickyAttach
0 (off), 1 (on)
0
Setting the value of this
parameter to 1 causes threads to
remember that they are attached
to the JVM.
This speeds up request
processing by eliminating
AttachCurrentThread and
DetachCurrentThread calls.
It can, however, have a
side-effect: recycled threads
which may be doing other
processing can be suspended by
the garbage collector arbitrarily.
Thread pools can be used to
eliminate this side effect for
other subsystems. For more
information about thread pools,
see the iPlanet Web Server
Administrator’s Guide.
jvm.trace
jvm.allowExit
0 (off), 1 (on)
5
Determines the trace level. For
servlet and JSP debugging, the
recommended level is 7. Level 5
displays servlet engine
messages. Level 6 displays
servlet and JSP engine
messages. Level 7 displays these
and other exceptions in the
browser.
0
Enables or disables exit from the
process.
Appendix
C
JVM Configuration
109
jvm12.conf Parameter Reference
Table C-1
jvm12.conf settings
Setting
Allowed Values
Default Value
Description
Specifies the Java compiler. See
your JVM documentation for
options that turn the JIT (just in
time) compiler on and off. This
should be set to NONE when
jvm.enableDebug is on.
java.compiler
OPTITDIR
A path
*
Specifies the path to the profiler
if the profiler is optimizeit.
nes.jsp.enabledebug
0 (off), 1 (on)
1
Enables or disables verbose JSP
compilation tracing.
For more information about
remote debugging, see Chapter
5, “Debugging Servlets and
JSPs.”
jvm.include.CLASSPATH
0 (off), 1 (on)
1
Specifies whether to include the
CLASSPATH environment
variable value in the
jvm.classpath setting.
nes.jsp.forkjavac
0 (off), 1 (on)
0
If on, Java compilation of JSPs
runs in a separate process.
jvm.serializeFirstRequest
0 (off), 1 (on)
1 for Linux,
AIX, and
Compaq
(DEC);
0 for other
platforms
If on, ensures that only one
request thread loads and
constructs a servlet object. Once
a servlet is loaded and
initialized, new requests to the
same servlet happen in parallel.
This setting must be on for
Linux, AIX, and Compaq (DEC).
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jvm12.conf Parameter Reference
Table C-1
jvm12.conf settings
Setting
Allowed Values
jvm.classpath
A path with
forward
slashes only
Default Value
Description
Specifies the path(s) to JAR files
dependent on the JVM. Enter
additional classpath values as
needed.
For example, if a JSP uses a bean
that is packaged in a JAR, add
the JAR path to the classpath.
If you are using a session
manager that uses a JDBC
driver, be sure to include the
driver’s JAR file in this
classpath.
* N:/App/IntuitiveSystems/OptimizeIt30D, where N is the drive on which OptimizeIt is installed.
Appendix
C
JVM Configuration
111
jvm12.conf Parameter Reference
112
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Appendix
D
Remote Servlet Profiling
You can use a profiler to perform remote profiling on the iPlanet Web Server to
discover bottlenecks in server-side performance. This appendix describes two
profilers:
•
The Optimizeit! Profiler
•
The HPROF Profiler
The Optimizeit! Profiler
You can purchase Optimizeit! from Intuitive Systems at:
http://www.optimizeit.com/index.html
Once Optimizeit! is installed using the following instructions, it becomes
integrated into iPlanet Web Server 6.0.
To enable remote profiling, make the following modifications in the jvm12.conf
files as appropriate:
jvm.enableClassGC=0
jvm.option=-Xrunoii
jvm.profiler=optimizeit
java.compiler=NONE
OPTITDIR=optimizeit_root_dir/OptimizeIt30D
When the server starts up with this configuration, you can attach the profiler (for
further details see the Optimizeit! documentation).
113
The HPROF Profiler
Also, update the PATH and NSES_CLASSPATH system variables to include the
profiler’s own jar files and dll files.
NOTE
If any of the configuration options are missing or incorrect, the
profiler may experience problems that affect the performance of the
iPlanet Web Server.
The HPROF Profiler
HPROF is a simple profiler agent shipped with the Java 2 SDK. It is a dynamically
linked library that interacts with the JVMPI and writes out profiling information
either to a file or to a socket in ASCII or binary format. This information can be
further processed by a profiler front-end tool such as HAT.
HPROF can present CPU usage, heap allocation statistics, and monitor contention
profiles. In addition, it can also report complete heap dumps and states of all the
monitors and threads in the Java virtual machine. For more details on the HPROF
profiler, see the JDK documentation at:
http://java.sun.com/products/jdk/1.2/docs/guide/jvmpi/jvmpi.html#hprof
To use HPROF profiling on Unix, follow these steps:
1.
To enable HPROF profiling, edit the jvm12.conf file as shown here:
jvm.printErrors=2
jvm.profiler=hprof
jvm.option=-Xrunhprof:options
#jvm.option=-Xrs must be commented out
java.compiler=NONE
Suggested options for using iPlanet Web Server with HPROF are:
jvm.option=-Xrunhprof:file=/tmp/hprof.txt,heap=all,format=a
or:
jvm.option=-Xrunhprof:file=/tmp/hprof.txt,cpu=samples,format=a
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
The HPROF Profiler
The syntax of HPROF is as follows:
-Xrunhprof[:help]|[:option=value,option2=value2, ...]
Using help lists options that can be passed to HPROF. The output is as follows:
Hprof usage: -Xrunhprof[:help]|[:<option>=<value>, ...]
Option Name and Value
--------------------heap=dump|sites|all
cpu=samples|old
format=a|b
file=<file>
Default
------all
off
a
java.hprof
(.txt for ascii)
send data over a socket write to file
stack trace depth
4
output cutoff point
0.0001
line number in traces? y
thread in traces?
n
dump on exit?
y
net=<host>:<port>
depth=<size>
cutoff=<value>
lineno=y|n
thread=y|n
doe=y|n
Description
----------heap profiling
CPU usage
ascii or binary output
write data to file
2.
You must also change a line in the iPlanet Web Server start script. The start
script file is server_root/https-server_id/start. Change the following line:
PRODUCT_BIN=uxwdog
to this:
PRODUCT_BIN=ns-httpd
3.
Start the server by running the start script. Since the server runs in the
foreground (the change in step 2), the command prompt returns only after the
server has been stopped.
4.
In another window or terminal, find the process ID of the server process.
% ps -ef | grep ns-httpd
This command lists two ns-httpd processes. Look at the PPID (parent process
ID) column and identify which of the two processes is the parent process and
which is the child process. Note the PID (process ID) of the child process ID.
5.
Send a SIGQUIT signal (signal 3) to the child process:
% kill -QUIT child_PID
Appendix
D
Remote Servlet Profiling
115
The HPROF Profiler
This displays the following ASCII menu in the window from where the start
script was invoked:
% start
iPlanet-WebServer-Enterprise/6.0
[LS ls1] http://test, port 9000 ready to accept requests
Default selection: alloc and heap dump
startup: server started successfully
SIGQUIT
A SIGQUIT has been received. Do you want to:
[ 0 ] continue program
[ 1 ] check & print one deadlock
[ 2 ] check & print all deadlocks
[ 3 ] dump thread stacks
[ 4 ] dump lock registry
[ 5 ] heap inspection
[ 6 ] hprof dump
[ 7 ] terminate program
Type number corresponding to selected action:
6.
Select menu option 6 by typing the number 6 and then typing the Enter key.
This causes HPROF data to be saved in the file specified in the jvm.option line
in jvm12.conf, for example /tmp/hprof.txt.
7.
Type 0 and press Enter to continue the program (the Web Server).
8.
To capture more HPROF profiles, repeat steps 6 and 7.
9.
To stop the Web Server, run the stop script from another window.
% ./stop
10. Undo the changes in steps 1 and 2 to return your Web Server to its original
configuration.
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iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
Index
A
about this book 7
accessTimeColumn
parameter for IWSSessionManager 60
parameter for JdbcSessionManager 68
API clarifications 71
API reference
JavaBeans 11
JSP 11
servlets 10
authdb attribute 19
auth-native element 19
B
beans 11
beans.10 examples directory 94
C
cache directories 42, 64
cache_dir
optional parameter to NSServletEarlyInit 96
CatchSignals
optional parameter to NSServletLateInit 96
characters
non-ASCII, in URIs 22, 92
class attribute 25
Class Manager 32, 41
ClassCache directory 42, 47
class-loader element 20
classpath
for JDK 40
for JVM 111
for legacy servlets 83
classpath attribute 20
client certificate, fetching 77
command-line JSP compiler 43
compiling
JSPs 43
servlets 31
configuring
JRE/JDK paths 39
JVM 35, 105
connection pooling, database 77
context
default 16
legacy 86, 90
optional parameter to NSServletService 96
contexts.properties 90, 96
cookie-name attribute 21
cookies method 76
D
database connection pooling 77
117
debugging
JSPs 50
servlets remotely 49
default context 16
default virtual server 79
delegate attribute 20
deletePool
parameter for IWSSessionManager 61
parameter for JdbcSessionManager 68
deleting
version files 42, 64
web applications 27
deploying web applications 27
description element 20
dir attribute 26
directives
for enabling JSPs 98
for enabling servlets 95
directories for servlets, legacy 81
!DOCTYPE declaration 18
domain attribute 25
dynamic reconfiguration 14
exceptions, sending to the client 50, 51
F
file extensions
.class 82
.jsp 80, 98
Filter API 20
filter element 20
filter-mapping element 20
flush-timeout attribute 24
form-hint-field attribute 23
form-login-session element 21
Forte for Java 51
forward 76
G
getAttribute 73
getParameter 23, 74, 93
E
enable attribute 21
enabling
IWSSessionManager 61
JdbcSessionManager 68
JDK or JRE 39
JSPs 42
legacy JSPs 80
legacy servlets 80
MMapSessionManager 63
servlets 32
session managers 56
SimpleSessionManager 66
enc attribute 22
encoding of non-ASCII characters in URIs 22, 92
examples
legacy 93
SSJS to JSP conversion 103
web applications 29
118
H
hangman examples directory 94
HPROF profiler 114
HttpServlet.service 73
HttpSession 71
I
ieClassId parameter 47
include 76
init-param element 21
insertPool
parameter for IWSSessionManager 61
parameter for JdbcSessionManager 68
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
installing
Forte for Java 51
JPDA 52
JRE or JDK 31, 37
Internationalization 22, 74, 92
Intuitive Systems
web site 113
isModifiedCheckAggressive context property 92
is-secure attribute 25
IWS_SERVER_HOME environment variable 27, 43
IWSHttpSession
source code 62
IWSHttpSessionManager 62
IWSSessionManager 58
enabling 61
parameters 58
source code 62
J
Jakarta 45
jars, classpath 111
Java Development Kit
see JDK
Java Runtime Environment
see JRE
Java Servlet API 10
Java Virtual Machine
see JVM
java.compiler parameter 110
JavaBeans 11
specifying classpath 111
JavaScript 99
JavaServer Pages
see JSP
JDBC driver 67, 77
for session management 60, 67
in JVM classpath 111
JdbcSessionManager 66
enabling 68
JDK 31, 37
classpath 40
downloading 38
enabling 39
installing 31, 37
path to 38, 39
specifying 38
supported versions 37
JPDA
debugging options 53
installing 52
JRE 31, 37
enabling 39
installing 31, 37
path to 39
JSP 10
accessing Java 10
API reference 11
cache directory 42, 64
command-line compiler 43
compiling 43
converting SSJS applications to 99
debugging 50
enabling 42
directives 98
enabling legacy 80
legacy configuration 79
package names 46
parameters 47
precompiling 43
specifying classpath for beans 111
tag libraries 47
using 9, 37
using Server Manager 41
using Server Manager for legacy 86
JSP 1.1 specification 47
JSP.10 examples directory 94
jspc command 43
jsp-servlet element 21, 42, 46
JVM
catching thread dumps 96
configuration 105
configuring 35
environment variables 106
more info 105
specification 105
jvm.allowExit parameter 109
jvm.classpath parameter 35, 111
Index
119
jvm.disableThreadRecycling parameter 108
jvm.enableClassGC parameter 107
jvm.enableDebug parameter 108
jvm.include.CLASSPATH parameter 35, 110
jvm.maxHeapSize parameter 35, 107
jvm.minHeapSize parameter 35, 107
jvm.option parameter 108
jvm.printErrors parameter 108
jvm.profiler parameter 108
jvm.serializeAttach parameter 109
jvm.serializeFirstRequest parameter 110
jvm.stickyAttach parameter 35, 109
jvm.trace parameter 109
jvm.verboseMode parameter 108
jvm12.conf file 35, 105
parameter reference 107
parameter for IWSSessionManager 59
parameter for MMapSessionManager 63
maxSessions
parameter for IWSSessionManager 58
parameter for MMapSessionManager 63
parameter for SimpleSessionManager 65
maxValueSize
parameter for MMapSessionManager 63
maxValuesPerSession
parameter for MMapSessionManager 63
MMapSessionManager 62, 64
enabling 63
parameters 63
multiple legacy servlet directories 82
N
K
keepgenerated parameter 47
L
largeFile parameter 47
login-config element 15
lookupPool
parameter for IWSSessionManager 60
parameter for JdbcSessionManager 68
M
magnus.conf file 95
magnus-internal/jsp 98
make examples directory 94
mappedfile parameter 47
map-to attribute 24
maxLocks
120
nes.jsp.enabledebug parameter 110
nes.jsp.forkjavac parameter 110
Nesting depth for request dispatchers 96
NSES_JDK 40
NSES_JRE 40
NSServletEarlyInit 95
NSServletLateInit 95
NSServletLayer.jar 62
NSServletService 95, 96
O
obj.conf file 95
ODBC driver 67
Optimizeit!
purchasing 113
OPTITDIR parameter 110, 113
output from servlets 34
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
P
package names
for JSPs 46
parameterEncoding context property 92
parameter-encoding element 22
param-name element 22
param-value element 22
password
parameter for IWSSessionManager 60
parameter for JdbcSessionManager 67
path
to JRE or JDK 39
path to JRE or JDK 38
persistent session manger 58, 62, 66
pooling of database connections 77
precompiling JSPs 43
preface 7
profiling
servlets remotely 113
provider
parameter for IWSSessionManager 60
parameter for JdbcSessionManager 67
R
reaper method 58, 63, 65
reaperActive
parameter for IWSSessionManager 60
parameter for JdbcSessionManager 68
reapInterval
parameter for IWSSessionManager 58
parameter for MMapSessionManager 63
parameter for SimpleSessionManager 65
reconfiguration, dynamic 14
registering
individual legacy servlets 83
legacy servlet directories 81
reloading legacy servlets 81
reload-interval attribute 20
remote profiling 113
remote servlet debugging 49
RequestDispatcher.forward 76
RequestDispatcher.include 76
requestDispatcherNestDepth
optional parameter to NSServletLateInit 96
response-buffer element 24
response-cookie element 24
role-mapping element 24
rules.properties 88
S
scratchdir parameter 47
security-constraint element 15
Server Manager 32, 41
for legacy servlets and JSPs 86
server.xml file 16
Server-Side JavaScript
see SSJS
service 73
servlet
optional parameter to NSServletService 96
Servlet 2.2 specification 10
Servlet 2.3 specification 20
<SERVLET> tag 33
servlet.jar 31
ServletByExt 80
ServletContext.getAttribute 73
ServletRequest.getParameter 23, 74, 93
ServletRequest.setAttribute 73
servlets 10
API clarifications 71
API reference 10
cache directories 42, 64
compiling 31
configuring legacy 83
configuring legacy global attributes 81
debugging remotely 49
directing files of a specific type to a specific
servlet 96
directing files of a specific type to a specific
servlet, legacy 89
enabling 32
Index
121
directives 95
enabling legacy 80
example of accessing 29
example of accessing legacy 82
legacy configuration 79
legacy directories 81
legacy examples 94
multiple legacy directories 82
non-ASCII parameters 22, 92
output 34
packaged, legacy 82, 92
performance 35
reloading legacy 81, 92
remote profiling 113
session managers 55
sessions 55
specifying legacy virtual paths 84
startup, legacy 81
using 9, 31
using a single class loader for legacy 93
using Server Manager 32
using Server Manager for legacy 86
virtual path translation, legacy 80
Servlets API Javadoc 72
servlets.properties 87, 96
session managers 55
default 58
deprecated 65
IWSSessionManager 58
JdbcSessionManager 66
MMapSessionManager 62
persistent 58, 62, 66
SimpleSessionManager 65
specifying 56
session-cookie element 25
SessionData directory 64
session-data-dir
parameter for IWSSessionManager 59
session-data-store
parameter for IWSSessionManager 59
session-failover-enabled
parameter for IWSSessionManager 59
sessionIdColumn
parameter for IWSSessionManager 60
parameter for JdbcSessionManager 68
session-manager element 25
122
sessions 55
HttpSession 71
ID generator 36, 70
overview 55
session-timeout element 15
session-tracking element 25
setAttribute 73
SHTML 33
SimpleSessionManager 65
enabling 66
singleClassLoader servlet property 93
size attribute 24
SmartHeap 36
source code
IWSHttpSession 62
IWSSessionManager 62
specifying
JDK or JRE 38
legacy servlet directories 81
legacy virtual servlet paths 84
path translations for legacy servlets 84
session managers 56
SSI 33
SSJS applications
converting to JSPs 99
stack trace
generating 51
StackSize directive 35, 36
startup servlets, legacy 81
static class members, sharing 93
stickyAttach parameter 109
T
table
parameter for IWSSessionManager 60
parameter for JdbcSessionManager 67
tag libraries 47
tempdir element 26
thread pools 35, 109
timeOut
parameter for IWSSessionManager 58
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
parameter for JdbcSessionManager 67
parameter for MMapSessionManager 63
parameter for SimpleSessionManager 65
timeOut attribute 21
timeOutColumn
parameter for IWSSessionManager 60
tools examples directory 94
U
unsafe URIs 76
updatePool
parameter for IWSSessionManager 61
parameter for JdbcSessionManager 68
uri attribute 26
url
parameter for IWSSessionManager 60
parameter for JdbcSessionManager 67
use-cookies attribute 25
use-precompiled parameter 47
username
parameter for IWSSessionManager 60
parameter for JdbcSessionManager 67
use-url-rewriting attribute 25
using
JSPs 9, 37
servlets 9, 31
web applications 9, 13
W
WAR file 9, 14
wdeploy utility 27
web applications 9, 13
deploying 27
directory structure 13
examples 29
using 9
web.xml file 14
clarifications 15
web-app element 26
web-apps examples directory 29
web-apps.xml file 16
element reference 19
example 18
webapps_enable variable 16
webapps_file variable 17
WEB-INF directory 14
X
-Xrs option and debugging 51
V
valueColumn
parameter for IWSSessionManager 60
parameter for JdbcSessionManager 68
version attribute 24
Version files 43, 64
version files 42, 64
virtual paths for legacy servlets 84
virtual server, default 79
vs element 26
Index
123
124
iPlanet Web Server, Enterprise Edition Programmer’s Guide to Servlets • May 2001
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