Big Fraction is a Java class that represents an immutable fraction, as held in a numerator and denominator. Calculations may be performed on this fraction, but the value is always held as a numerator/denominator pair. Therefore, no precision is lost. The fraction may be top-heavy, but is reduced when printed. The value can be converted into floats if desired, although precision will invariably be lost, and some large fractions (such as calculations for pi) can not be converted if the values of BigInteger exceed the range capable of floats.
The Bright Side Framework provides ready-to-use, high-level J2EE components which will help you quickly build business J2EE applications accessed by rich Java/Swing clients on HTTP. The components are loosely coupled, which allows you to pick only the one you need. The Remoting transparently encapsulates EJB calls inside HTTP. The List Of Values provides nice features for the reference data of all business applications. The Smart Value Object tracks the client modifications and manages the optimistic concurrency during client/server communication. The Remote Iterator allows a rich client to fetch the results of a SQL statement, block by block.
CouchUnit is a JUnit extension that helps administer tests run against CouchDB. It mimics the syntax and feel of DBUnit by helping developers write tests that load XML style datasets to place databases in known states between integration tests. A number of standard operations are used to store and remove CouchDB documents. Any number of documents may be declared within a single CouchUnit dataset.
Ganymed SSH-2 for Java is a library that implements the SSH-2 protocol in pure Java (tested on J2SE 1.4.2, 5, and 6). It allows one to connect to SSH servers from within Java programs. It supports SSH sessions (remote command execution and shell access), local and remote port forwarding, local stream forwarding, X11 forwarding, SCP, and SFTP. There are no dependencies on any JCE provider, as all cryptographic functionality is included.
Gecode/J is a Java interface to the Gecode C++ constraint progamming library. Gecode/J is mainly aimed at education, presenting a slightly simplified interface compared to Gecode. Using Gecode/J, modeling constraint problems, programming custom propagators, branchings, and search engines are possible directly in Java. There is also an interactive graphical search tool, the Gecode/J Explorer.