Can not use Generics in JSP

[danielywoo]

Hi,

I can not use generics in JSP, for example:

<%
 List<User> list = new ArrayList<User>(1000);
 for (int i = 0; i < 1000; i++) {
 User u = new User("test" + i, i);
 list.add(u);
 }
 test.insertAllUserList(list);
 %>

The console shows strace:

11:53:16,546 ERROR [[jsp]] Servlet.service() for servlet jsp threw exception
org.apache.jasper.JasperException: Unable to compile class for JSP
An error occurred at line: 4 in the jsp file: /test_slsb_entity_insert.jsp
Generated servlet error:
Syntax error on token "<", invalid AssignmentOperator
An error occurred at line: 4 in the jsp file: /test_slsb_entity_insert.jsp
Generated servlet error:
Syntax error on token "=", != expected
An error occurred at line: 4 in the jsp file: /test_slsb_entity_insert.jsp
Generated servlet error:
Syntax error on token "new", delete this token

[danielywoo]

Does anybody know the behavior of tomcat jsp compiler? Why it doesnot support JDK5.0 features like generics?

[danielywoo]

I found the reason.
delete jdt compiler and copy ant.jar, tools.jar to tomcat.sar/conf
set compiler to 1.5 in default web.xml

[nikolaymetchev]

This issue is duscussed in the Wiki:
http://wiki.jboss.org/wiki/Wiki.jsp?page=402UpgradeIssues
However I haven't been able to find out why the JDT compiler cannot be used for compiling Java 5 code. Is there a JIRA/Bugzilla issue to do with this?

[p_saville1]

JBoss IDE or Eclipse WTP, not sure which is doing my JSP compilation... But in the problems tab, all my JAVA 5.0 Generics code in JSPs show errors.

I am using Tomcat 5, and the JSPs compile and run fine in Tomcat... Just my IDE errors list is filling up with Generics errors in JSPs.

Is there a way to fix this?

[j2ee_junkie]

What I did to solve this issue was to specify which JSP compiler to use in my web.xml file.

<web-app>
...
 <!-- specify jsp's compiler and java 1.5 standard -->
 <servlet>
 <servlet-name>jsp</servlet-name>
 <servlet-class>org.apache.jasper.servlet.JspServlet</servlet-class>
 <init-param>
 <param-name>compilerSourceVM</param-name>
 <param-value>1.5</param-value>
 </init-param>
 <init-param>
 <param-name>compilerTargetVM</param-name>
 <param-value>1.5</param-value>
 </init-param>

 <init-param>
 <param-name>fork</param-name>
 <param-value>false</param-value>
 </init-param>
 <init-param>
 <param-name>xpoweredBy</param-name>
 <param-value>false</param-value>
 </init-param>
 <load-on-startup>3</load-on-startup>
 </servlet>
...
 <!-- The mapping for the JSP servlet -->
 <servlet-mapping>
 <servlet-name>jsp</servlet-name>
 <url-pattern>*.jsp</url-pattern>
 </servlet-mapping>
...
</web-app>

enjoy, cgriffith