AlgART Libraries is a collection of Java libraries for processing arrays and matrices. It features63-bit addressing of array elements (64-bit long int indexes), a memory model concept (allowing data to be stored using different schemes, from RAM to mapped disk files), wide usage of lazy evaluations, built-in multithreading optimization for multi-core processors, and a wide set of image processing algorithms over matrices. Almost all classes and methods are thoroughly documented via JavaDoc.
gedcom4j is a Java library for loading (parsing) and saving GEDCOM 5.5 or 5.5.1 files to/from a Java object hierarchy, which can be manipulated by your code as you see fit. Please note that gedcom4j is not an application. It is a library for parsing, manipulating, and writing GEDCOM data in your own programs.
Xtempore is a lightweight, modular, and powerful XML-based domain independent templating language. It's essentially a programming library which provides flexible tools for transforming an object (model) and an XML document (template) into another XML document. Xtempore is implemented in Java and requires JRE 1.5 or later and slf4j for logging.