off-topic

Eclipse + Maven + AppEngine: Invalid classpath publish/export dependency

While working with Eclipse and Google Plugin for Eclipse the Maven Integration Plugin I ran into the problem that the dependency on the JDO API library jdo2-api-2.3-ea.jar appears in the App Engine SDK and in the Maven dependencies imported from another project. The Eclipse Classpath Dependency Validator showed the following error message:

Invalid classpath publish/export dependency /local/eclipse/galileo/plugins/com.google.appengine.eclipse.sdkbundle_1.2.2.v200907291526/appengine-java-sdk-1.2.2/lib/user/orm/jdo2-api-2.3-ea.jar. The project contains another dependency with the same archive name.

The solution for this problem was using the notion of explicit dependency exclusion of Maven 2.x in the pom.xml.