Groovy is an agile, dynamic language for the JVM which combines many features from languages like Python, Ruby, and Smalltalk and makes them available to Java developers using a Java-like syntax. It is designed to help get things done on the Java platform in a quicker, more concise, and fun way. It can be used as an alternative compiler to javac to generate standard Java bytecode to be used by any Java project or it can be used dynamically as an alternative language, such as for scripting Java objects, templating, or writing unit test cases.
XMLUnit provides assertions and supporting class libraries to test various properties of generated pieces of XML using a popular testing framework. It supports finding the differences between two pieces of XML, validating documents against DTDs or XML Schemas, testing the results of XPath expressions, or asserting properties of Nodes exposed via DOM traversal. Two branches exist: one that supports Java and JUnit and one that supports the .NET Framework and NUnit.
The Java Application Monitor (JAMon) is a free, simple, high performance, thread safe, Java API that allows developers to easily monitor production applications. JAMon can be used to determine application performance bottlenecks, user/application interactions, and application scalability. JAMon gathers summary statistics such as hits, execution times (total, average, minimum, maximum, standard deviation), and simultaneous application requests. JAMon statistics are displayed in the sortable JAMon report.
OpenEJB is a simple, lightweight Enterprise JavaBeans (EJB) container and server. You can embed OpenEJB in your own applications, or in a Web application server like Tomcat, or run it as a standalone EJB server. It supports EJB 3.0, 2.1, 2.0, and 1.1, and has partial support for EJB 3.1.
Jaffa (Java Application Framework For All) is an enterprise-focused Java framework for rapid application development. It provides a complete Java Web application development stack, extending exsiting projects like Tomcat and Struts at the frontend with MVC-based web widgets, all the way through to a high-performance lightweight O/R persistence engine, with plenty of rich features in between including rules engines, declarative application, and data security. In addition to the runtime framework, there is a suite of component templates and other tools for rapid application development, including a TogetherSoft plug-in for UML intergration.
MARF is a general cross-platform framework with a collection of algorithms for audio (voice, speech, and sound) and natural language text analysis and recognition, along with sample applications (identification, NLP, etc.) of its use. MARF can run distributed over the network (CORBA, Java RMI, and Java XML-RPC Web Services) and may act as a library in applications or be used as a source for learning and extension.
SubEthaSMTP is an easy to understand Java library that provides a receptive SMTP server component. By plugging this component into your Java application, you can easily receive SMTP mail using a simple abstract Java interface. Also included is a small sub-project called Wiser, an easy to use incoming mail testing framework.
Pavlov is a multiple choice study system in which flashcards magically shuffle themselves to optimize study time. They sing and otherwise entertain you while you study. It uses easy-to- write "pluglets" for feedback mechanisms (entertainment) and question choice strategies (efficiency).