JSX serializes Java objects to XML. You can persist objects, evolve them, and send them over the network and between applications. Your object data becomes human-readable and human-writable. You can test it, search it, profile it, audit it, and edit it with ordinary text and XML tools. JSX handles all POJOs and also all classes that require Java's own object serialization.
OpenGrok is a fast and usable source code search and cross reference engine. It helps you search, cross-reference, and navigate your source tree. It can understand various program file formats and version control histories like Mercurial, Bazaar, Git, ClearCase, Perforce, SCCS, RCS, CVS, or Subversion. In other words, it lets you grok (profoundly understand) the source.
Apache Cocoon is a Web development framework built around the concepts of separation of concerns and component-based Web development. Cocoon implements these concepts around the notion of "component pipelines", each component on the pipeline specializing on a particular operation. This makes it possible to use a Lego(tm)-like approach in building Web solutions, hooking together components into pipelines without any required programming.
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.
The eobjects.org MetaModel is a project created for maximum reuse of a SQL-compliant domain model of the database domain. The MetaModel is a model that contains classes that represent the structure of a database (schemas, tables, column, relationships) and interaction with the database (queries) in a SQL/LINQ-like way. In short, it is a model for modelling data in databases and other datastores. With MetaModel you can query different datastores like databases, CSV files, Excel spreadsheets, MS Access files, and XML files using the same approach and the same domain model.