db4o is an object database for Java and all .NET environments. Its features include ACID transactions, automatic class schema recognition, query-by-example, a S.O.D.A. object querying API, native queries, LINQ support on .NET, callback methods, memory files, cascade-on-delete, multi-threaded access, and Java Webstart and servlet support.
ServoMaster provides hardware independent abstractions to servos and servo controllers. It has implementations for several servo controller families, including Phidget, Pololu, Parallax, and SSC. It has support for servo and controller metadata, introspection, and capabilities discovery.
Servertec Persistent Object Store (POS) is a high-performance cross-platform object oriented database engine written entirely in Java. With it, developers can easily create standalone database applications, including mobile and wireless devices and embedded systems. It can be used on any platform that supports Java version 1.1.x or later.
SuperWaba is a VM for PDAs. Because of the way it was written, you can use Java to develop programs for it. It supports exceptions, threads, many user interface controls, double and long 64-bit types, grayscale, color, 3D controls, and JNI and Java libraries, among other features. The project has been superseded and replaced with TotalCross.
The JavaBluetooth Stack is a 100% Java implementation of the Bluetooth specifications version 1.1. It uses the javax.comm package to address the Bluetooth chip, and implements the JSR-82 (javax.bluetooth) API. It currently supports HCI, L2CAP, and SDP. Support for RFCOMM, TCS, and SCO is planned, as well as implementations of specific Bluetooth profiles such as the Handsfree-Profile and the Generic Audio/Video Distribution Profiles. Deployment on the TINI Embedded Java platform is possible.
The XView4Struts project is an extension to the Jakarta Struts Framework. Its main purpose is to eliminate the need to use tag libraries and JSP pages. The view is pure HTML, and interaction between the view and the model is transparent to the developer. This approach offers faster development, better division of work, a more pure MVC design pattern, reusable view components, and easier maintenance.
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!
jRate is an extension of the GNU GCJ compiler front-end and runtime system that adds support for most of the features required by the Real-Time Specification for Java (RTSJ), including threading constructs with real-time constraints, asynchronous event handling, and memory regions. It was initially developed at Washington University in St. Louis and is released under a license similar to GCC's GPL license that allows non-GPLed programs to be compiled and linked.