FreeMarker is a template engine that was originally designed so that servlet-based applications could keep graphical design separate from application logic. The templates provide an easy and highly flexible way to generate any kind of text output (HTML, PostScript, TeX, source code, etc.) from a variety of data sources such as Java objects, Jython objects, XML object models, and more.
MinML is an XML parser written in Java which implements nearly all of the XML language (it ignores DTDs). It was developed for use in small embedded systems and has a code footprint of less than 10Kb. It is designed to minimise the amount of heap space consumed when parsing a document. MinML implements the SAX1 interface.
MinML-RPC is an implementation of XML-RPC server written in Java. It was designed to be used in embedded systems where storage space is at a premium. The code is quite compact, and it was also designed to minimize the heap space used by the program when executing a procedure call. The distribution includes the parser, the XML-RPC server implementation, and a small, high-performance HTTP 1.1 server.
NinjaRMI is a free, ground-up reimplementation of Java Remote Method Invocation. It supports a number of features not found in Sun's RMI suite, including new communication semantics (one-way, unreliable, and multicast RMIs) and API enhancements (e.g., the ability to determine the hostname of the peer in an RMI connection). And, because all of the source code is provided, you're free to add new features as needed.
Pnuts is a scripting language totally written in Java. Users can use Pnuts to access the Java environment interactively. This helps developers to test their programs efficiently and easily. An interesting usage for this language is to be used as "glue" for JavaBeans or beween any Java API. Also, it can be embedded in a Java program to make processing more flexible.