Ant Build File Changes for Java Web Projects in NetBeans IDE 6.1

While working with a Java Web Application in NetBeans, I noticed some slight changes in the Ant build file for my project between NetBeans 6.0 and 6.1. This article explores some of the problems these changes caused to help out anyone with similar issues.

I started with a Java Web Application that was created in NetBeans 6.0.1. After adding some JSP files and several Java source files, I committed everything in the project to my CVS repository.

For some of my projects, I utilize the Hudson continuous integration build server. Using a standard deployment of Hudson, I configured the project to poll the SCM every 60 minutes, check out the code from CVS (if changes had been committed), and trigger the NetBeans project’s Ant build file (calling several specific targets like compile, dist, and so on.

My builds have been functioning correctly for several weeks using this standard setup. I recently opened one of those projects in NetBeans 6.1 Beta and have been thoroughly enjoying the new features (faster startup, better JSP parsing in the Source Editor). After adding some JAR files as libraries and making several configuration changes, I committed the entire project (particularly the build-related files in the nbproject directory).

Suddenly, my build for that project started failing. The console output reported by Hudson was :

-init-check:

BUILD FAILED
D:/projects/hudson-server/data/jobs/MyWebProjectl/workspace/nbproject/build-impl.xml:149: 
The Java EE server classpath is not correctly set up. Your active server type is Tomcat55. 
Either open the project in the IDE and assign the server or setup the server classpath manually. 
For example like this:
   ant -Duser.properties.file= (where you put the property “j2ee.platform.classpath” in a .properties file)
or ant -Dj2ee.platform.classpath= (where no properties file is used)

Total time: 2 seconds
finished: FAILURE

I undid the configuration changes one by one, but the build failed regardless of what I reset. Apparently the property j2ee.platform.classpath is now required. I did a DIFF on the nbproject/build-impl.xml file and discovered several changes.

The -init-check target includes property checks including this new one :

<fail unless="”j2ee.platform.classpath”">
     The Java EE server classpath is not correctly set up. Your active server type is   
     ${j2ee.server.type}.Either open the project in the IDE and assign the server or 
     setup the server classpath manually.For example like this:
     ant -Duser.properties.file= 
     (where you put the property “j2ee.platform.classpath” in a .properties file)
     or ant -Dj2ee.platform.classpath= (where no properties file is used)
</fail>

I hadn’t really taken notice of this property in the build file before, but it is referenced in a number of other targets such as: -init-macrodef-javac, -init-macrodef-junit, -init-macrodef-java, -init-macrodef-nbjpda, -init-macrodef-debug, compile-jsps, -do-compile-single-jsp, connect-debugger, javadoc-build, -do-compile-test, -do-compile-test-single

Not being able to find a definition of the property anywhere in the build file, I looked through the project’s project.properties file among the list of defined properties. The property j2ee.platform.classpath was not defined. Thus, I’m assuming this is passed into the build file dynamically by NetBeans?

In general I wouldn’t care, but when running the build file via Ant inside Hudson, the property j2ee.platform.classpath is never passed in. Hudson DOES allow you to pass properties and values to the build file, so I suppose I can specify the value manually, but I would like to keep the number of per project customizations to a minimum to maintain a low level of maintenance.

Unless this causes some problem with the project properties in the build system, I would suggest the following fix for anyone who is experiencing a similar issue. Open your project’s project.properties file. Navigate to the section that contains these properties: j2ee.platform=1.4 j2ee.server.type=Tomcat55

Add a new line that specifies a blank j2ee.platform.classpath property such as this:

j2ee.platform=1.4
j2ee.platform.classpath=
j2ee.server.type=Tomcat55

Now, if the project.properties file is committed to CVS, a Hudson build can be triggered, and the FAIL check in the build-impl.xml file will pass. I ran some quick tests with the project, and everything with the project inside NetBeans still seems to work fine. I would propose to the NetBeans team to have the j2ee.platform.classpath property automatically added to the project.properties file.