Variable Length Argument List with Tomcat/JSP fails to compile.

[smm1]

I have a method that takes a variable length arg list:
"testmethod(int...in)".

Using this method from a 'regular' java program (i.e. via 'main') works
just fine, but when invoked from Tomcat/JSP I get an error:

"Generated servlet error:
The method testmethod(int[]) in the type testclass is not applicable
for the arguments (int, int, int)"

The java:

package testpackage ;
public class testclass {
public static int testmethod(int... in) {
return in[1] ;
}
public static void main(String[] args) {
System.out.println(testmethod(1,2,3)) ;
}
}

The JSP:
<%@ page import="testpackage.testclass.*" %>
<%
out.println(testpackage.testclass.testmethod(1,2,3));
%>

I'm using Tomcat 5.5.12 and java 1.5.0_06.

Any ideas on how I can get this JSP to compile? Thanks for any help.

 

[Juha Laiho]

(e-mail address removed) said:

I have a method that takes a variable length arg list:
"testmethod(int...in)".

Weren't vararg methods implemented in Java 1.5? If so, there is your
problem. By default the JSP compiler still in Tomcat 5.5 handles
Java 1.4.

This can be changed with Tomcat configuration for the Jasper servlet; see:
http://tomcat.apache.org/tomcat-5.5-doc/jasper-howto.html#Configuration

 

[smm1]

Juha-
Thanks for pointing me in the right direction.

Eventually I got it going by downloading current copies of:
- jasper-compiler-jdt.jar
- jasper-compiler.jar
- jasper-runtime.jar
This solves the problem, with no config required.

But before, that I found another solution:

1. Adding the following lines to conf/web.xml
<servlet>
<servlet-name>jsp</servlet-name>

<servlet-class>org.apache.jasper.servlet.JspServlet</servlet-class>

<init-param>
<param-name>xpoweredBy</param-name>
<param-value>false</param-value>
</init-param>
<!-- added these lines...
<init-param>
<param-name>compilerTargetVM</param-name>
<param-value>1.5</param-value>
</init-param>
<init-param>
<param-name>compilerSourceVM</param-name>
<param-value>1.5</param-value>
</init-param>
....
This by itself does not solve the problem.

2. remove common/lib/jasper-compiler-jdt.jar

3. Download the current ant release from
http://ant.apache.org/bindownload.cgi and copy ant.jar to
common/lib/ant.jar

4. Copy tools.jar from $JAVA_HOME/lib to common/lib

 

[smm1]

Juha-
Thanks for pointing me in the right direction.

Eventually I got it going by downloading current copies of:
- jasper-compiler-jdt.jar
- jasper-compiler.jar
- jasper-runtime.jar
This solves the problem, with no config required.

But before, that I found another solution:

1. Adding the following lines to conf/web.xml
<servlet>
<servlet-name>jsp</servlet-name>

<servlet-class>org.apache.jasper.servlet.JspServlet</servlet-class>

<init-param>
<param-name>xpoweredBy</param-name>
<param-value>false</param-value>
</init-param>
<!-- added these lines...
<init-param>
<param-name>compilerTargetVM</param-name>
<param-value>1.5</param-value>
</init-param>
<init-param>
<param-name>compilerSourceVM</param-name>
<param-value>1.5</param-value>
</init-param>
....
This by itself does not solve the problem.

2. remove common/lib/jasper-compiler-jdt.jar

3. Download the current ant release from
http://ant.apache.org/bindownload.cgi and copy ant.jar to
common/lib/ant.jar

4. Copy tools.jar from $JAVA_HOME/lib to common/lib