SoapUI is a free and open source cross-platform functional testing
The OWASP ZAP core project
Programmer-friendly testing framework for Java and the JVM
Load testing tool for analyzing and measuring performance of services
Flexible, lightweight multi-language test reporting tool
Most popular Mocking framework for unit tests written in Java
Test automation made simple
State of the art mutation testing system for the JVM
Coverage-guided, in-process fuzzing for the JVM
The Open Source Test Automation Platform
API automation and load testing framework
Gateway service providing dynamic routing, monitoring and more
Android unit testing framework
Benchmarking tool
Database Subsetter and Relational Data Browser
Java GUI-Less browser, supporting JavaScript, to run against web pages
Enterprise integration testing framework
Easy to set up bug tracking with Java
Automated tests with databases: prep, verify, restore tables
The Interactive Exernal Accessor Tool for develop, test and support.
A Java Utility Class To Create Combinations of Existing Arrays.
Simple example of draw and rotate 3D box
A tool that inserts code into Java class files for logging