Some examples to discuss organizing classes into packages

Hosted and command-line calculator of cohesion metrics for Java code

Object oriented JSON library wrapper for javax.json.

DevOps team assistant that helps you merge, deploy, and release GitHub-hosted apps and libraries

Object oriented JSON library wrapper for Jackson.

Nullfree will fail your build if your project has a null.

True Object-Oriented Java Web Framework without NULLs, Static Methods, Annotations, and Mutable Objects

Object-Oriented Java primitives, as an alternative to Google Guava and Apache Commons

Fan club for Elegant Objects programmers