Azureus : Java BitTorrent Client
- An advanced multiplatform BitTorrent client written in Java that includes a tracker and a torrent maker components needed to run a BitTorrent solution; available in many languages. Latest release is 3.0.5.2, 2008-04-15.
FreeMarker
- A generic tool to generate text based on output templates; generation of HTML web pages.
IcedTea
- This project provides a harness to build the source code from the OpenJDK project using Free Software build tools and provides replacements for the binary plugs with code from the GNU Classpath project.
JBuilder for Linux
- An application server-independent enterprise class IDE built on open source Eclipse. N.B. Software can be downloaded free, but it is proprietary software.
JFlex - The Fast Scanner Generator for Java
- A lexical analyzer generator (also known as scanner generator) for Java, written in Java. Latest release is 1.4.1, 2004-11-07.
JUSB - Java USB (for GNU/Linux)
- Java access to USB, currently using kernel 2.4 Linux-USB support; latest version is 0.4.4, 2001-02-14. N.B.: this is a popular project with lots of daily downloads. (2006)
Jetty Java HTTP Servlet Server
- An open source, standards-based, full-featured web server implemented entirely in java. Latest stable release is 6.1.0, 2006.
Jython Home Page
- Jython is an implementation of the Python language written in 100% Pure Java, and seamlessly integrated with the Java platform. Latest release is 2.2, 2007-08-23.
Kaffe.org - Kaffe Virtual Machine
- A clean-room implementation of the Java virtual machine, plus the associated class libraries needed to provide a Java runtime environment. Latest release is 1.1.7, 2006-03-27.