Apache Maven 3 is required to build Apache Commons Weaver. Things to know:
Because of the various interdependencies among modules, certain goals of certain Maven plugins will fail until the project has been added to your local repository using mvn install, e.g. mvn dependency:list, mvn dependency:tree, and possibly others.
The Commons Weaver site includes the report generated by the clirr-maven-plugin which is currently unable to run on Java 8. Also, the Commons Weaver site generation process runs out of permgen space when built with default JVM settings (on applicable Java versions); the MAVEN_OPTS environment variable can be used to set MaxPermSize. -XX:MaxPermSize=128m seems to be adequate on Java 7.