The Packer project provides a new API on top of the GridbagLayoutManager which eliminates the use of the GridbagConstraints objects. It makes it much easier to create compact and functional code blocks which are simple to write and move around in your layout design so that you can quickly developer GUIs.
Welcome to the Timing Framework, a library for making Java animation and timing-based control easier. This project provides a framework and sample code for time-based animations in Swing and SWT. The 1.1 "classic" version of this library is fully documented in chapters 14-15 of the book Filthy Rich Clients. Newer releases of the library support a default timer; are multi-thread safe; go faster; use less memory; support Android, Swing, and SWT; and have an improved API.
VisualVM - All-in-One Java Troubleshooting Tool. VisualVM is a visual tool integrating several commandline JDK tools and lightweight profiling capabilities. Designed for both production and development time use, it further enhances the capability of monitoring and performance analysis for the Java SE platform.