lambdaj is a Java library that allows you to manipulate collections in a pseudo-functional and statically typed way. The main purpose of lambdaj is to partially eliminate the burden of writing (often nested and poorly readable) loops while iterating over collections. In particular, it allows you to iterate a collection in order to filter its items on a given condition, convert each item with a given rule, extract a given property from each item, sort the items on the values of one of their properties, group or index the items on the value of one or more properties, invoke a method on each item, or aggregate the items or the values of one of their properties. It allows all this without having to write a single explicit loop.
eXtcos is an extensible JVM component scanner, similar to the component scanning feature of Spring. It is a small library solely focused on the task of class path scanning. It provides an easy-to-use query language for requesting the classes. This is a refreshing change to the boiler plate code you need to use the Spring classes for your own needs. You can get several different kinds of classes with just one query. You can use eXtcos for finding plug-ins for your application, classes meant to be run inside your container or framework, and the like. eXtcos is basically a base library on which other applications, containers, and frameworks can depend on.
tadedon is a set of utilities that form a foundation for applications written with one of the many Java frameworks, such as GWT, GIN, Guice, Google App Engine, commons-configuration, and many others. It lets you specify the default configuration of your application and upgrade it automatically on each new release. It can redirect all java.util.logging to slf4j and easily configure logback. It can bind application configuration in a Guice module. It supports @PostConstruct and @PreDestroy annotations (JSR 250) in Guice applications. It lets you annotate your methods with @Transactional annotation. It supports Guice injector stage in your Web application. It lets you test your Guice managed servlets and filters without needing a real servlet container. It lets you use Guice Matchers for matching super class, interface, and type literal annotations. It can inject event bus to your GWT applications with the help of GIN.
TIXI is a fast and simple XML interface library for applications written in C, C++, Fortran, Java, and Python. Although simplified and somewhat restricted compared to a fully-fledged XML processing library, it can create documents, create and delete nodes, and add and remove element attributes. Routines for reading and writing text nodes and nodes holding integer and floating point numbers are included, along with routines that process aggregates of these simple types for the processing of geometric data, multidimensional arrays, or arrays of vectors.