I want to know how one can compress javascriptfiles using maven. I have lready visited webistes like http://mojohaus.org/javascript-maven-tools/guide-webapp-development.ht
The best and the most advanced one I found till today is wro4j. The idea for the library and the Maven plugin is different from everything I was able to find on the internet, combining pretty much every tool available into one standalone library. Amazing.
You have two modes with wro4j available - first is to operate dynamically as a filter in Java application, second is to use build-time solution with Maven plugin. It's all really straightforward and well explained on the project documentation section, so take a look and dive deep. There are fully operational and well explained examples on how to integrate wro4j with one's application or with Maven build process.