ApacheDS is an LDAP and X.500 experimentation platform. Its backend subsystem and frontend are separable and independently embeddable. It provides a server side JNDI LDAP provider that directly interacts with the backend storage. It is powered by SEDA (Staged Event-Driven Architecture), which can handle large amounts of concurrency.
Morph is a Java framework that eases the internal interoperability of an application. As information flows through an application, it undergoes multiple transformations. Morph provides a standard way to implement these transformations. In addition to providing a framework for performing transformations, Morph provides implementations of many common transformations. It has been built from the ground up for flexibility and extensibility, and it integrates seamlessly with dependency injection frameworks such as Spring, PicoContainer, and Hivemind.
OpenArm is an implementation of the Open Group's Application Response Measurement (ARM) standard. It provides a complete implementation of the ARM 4.0 Java interfaces, as well as ARM agent functionality that allows you to record your transaction events as log4J logging events, JMS messages, SNMP traps, JMX notifications, or as records in a relational database.
The Hecl Programming Language is a high-level scripting language implemented in Java. It is intended to be small, extensible, extremely flexible, and easy to learn and use. It is intended as a complement to the Java programming language, not a replacement. As such, it tries to do well what Java doesn't, and leaves those tasks to Java for which it is best suited. It is also easy to add Hecl to Java, or write new Hecl commands in Java. It aims to be a very immediate language so that you can pick it up and start doing useful things with it quickly. Of particular interest is the fact that it's small enough to run on Java-enabled cell phones, so you can quickly script applications for them!
Tapestry Palette is a plugin for Eclipse that builds upon the Spindle plugin. The palette provides a tree view of Tapestry component libraries, a component inspector to discover parameters available with links to HTML documentation, drag and drop addition of Tapestry component references to templates, and a Property Sheet for editing of component bindings. The plugin can be installed from within Eclipse via an update site.