1.www.sourceforge.net Ding Ding's open source community. Open source code in different languages has. The disadvantage is that it is not sorted according to the category and is not convenient. And many projects have no good maintenance and support.
2.Http: //www.java-source.net class is very fine, and it is easy.
3.http://www.apache.org/ Very rich. General development J2EE is always available. At least there should be a log4j bar :)
4Http: //www.opensymphony.com/ Types, but each is a boutique. Webwork, quartz, oscache ... And it is an absolute enterprise application.
