Now continued as OculiX — see oculix.org
The OWASP ZAP core project
SoapUI is a free and open source cross-platform functional testing
Programmer-friendly testing framework for Java and the JVM
Flexible, lightweight multi-language test reporting tool
Most popular Mocking framework for unit tests written in Java
Test automation made simple
API automation and load testing framework
Gateway service providing dynamic routing, monitoring and more
SoloPi Automated Testing Tool
The Open Source Test Automation Platform
State of the art mutation testing system for the JVM
Java GUI-Less browser, supporting JavaScript, to run against web pages
Enterprise integration testing framework
Database Subsetter and Relational Data Browser
Editor for Fixed Width, Csv and Existing Xml files.
The Interactive Exernal Accessor Tool for develop, test and support.
Automated tests with databases: prep, verify, restore tables
A web application for testing webservices
A Java Utility Class To Create Combinations of Existing Arrays.
Simple example of draw and rotate 3D box
Test Automation framework intended for coarse-grained testing