A WYSIWYG editor applet/component. Provides word processor-like features, like a spelling checker, for XHTML markup creation.

Java-based object-oriented framework for interactive business applications. By APCON WPS. [Framework is commercial; other components are open source, BSD-like]

A meta architecture for the Java virtual machine.

Allows treating a byte array as a file. [Open Source, GPL]

Simple Java/XML rules engine suitable for personalization, workflow, and business rules. [Open Source]

Report generator and print preview JavaBean.

Java-based object oriented platform for MUDs and other modular, possibly distributed applications. [Open Source]

A binding for SDL (Simple DirectMedia Layer) written in java. Now you can use SDL and still program with Java. [Open source, LGPL]

Provides the following services: implementation of complete UML 1.3 physical metamodel, easy to use interfaces, event notification, undo/redo support, reflective API, XMI loading/saving. [Open Source, LGPL]

A cross platform audio I/O library. [Open source]