Need the source and/or the Javadoc of a java library?
Try http://www.jsourcery.com/. It contains the clickable source of many libraries and applications, like Spring, Apache (Commons), JUnit, ActiveMQ etc. etc. Unfortunately, their generator is not available.
The link is no more active. JSourcery
Very cool! Seems very useful, and replaces a Lot of links in my “Developer” favorites folder!