Sourcetrail is a productivity tool for software developers on Windows, Mac and Linux. It uses static source code analysis to provide a visualization that lets you follow calls and other dependencies.
an Open Source Probabilistic Information Retrieval library, a highly adaptable toolkit to allow developers to easily add advanced indexing and search facilities to their own applications.
search for Java projects. The examples extracted from open source search engine understands the semantics of Java, so the search yields more accurate results than a text search. The site also provides the ability to rate examples
Searching all methods, classes, and packages of J2SE, J2EE, and J2ME. Anyone that has an example of the Java at the Doc level can entry their 2 cents worth.