Batik is a Java-based toolkit for applications that want to use images in the Scalable Vector Graphics (SVG) format for various purposes, such as viewing, generation, or manipulation. It gives developers a set of core modules (parsers, generators, DOM implementation) which can be used together or individually, and be highly extensible. It comes with a full-fledged SVG viewer.
Melati is a tool for building Java-programmed websites backed by a database. It provides a generic database admin system, an object layer where the database is seen as a collection of Java objects, and transparent caching of commonly used records, selections and "computed objects", via a transparent persistence layer on top of JDBC. Melati also provides low level, fine-grained access control through capabilities, and a rapid templating mechanism, using "templets" (sub-templates) for rendering interface elements (e.g. HTML input boxes, dropdowns). Melati is closely integrated with the popular WebMacro templating engine.
4Suite is a Python-based toolkit for XML and RDF application development. It features a library of integrated tools for XML processing, implementing open technologies such as DOM, RDF, XSLT, XInclude, XPointer, XLink, XPath, XUpdate, RELAX NG, and XML/SGML Catalogs. Layered upon this is an XML and RDF data repository and server, which supports multiple methods of data access, query, indexing, transformation, rich linking, and rule processing, and provides the data infrastructure of a full database system, including transactions, concurrency, access control, and management tools. It also supports HTTP, RPC, SOAP, and FTP, plus APIs in Python and XSLT.
Avalon is Apache's Java Server Framework project. It is separated into six subprojects: Framework, Excalibur, LogKit, Cornerstone, Phoenix, and Apps. Its purpose is to simplify server side programming for Java-based projects. It formalizes several best practices and patterns for server side programming. Framework describes the interfaces and contracts for the component-based architecture. Excalibur provides a number of useful components and utilities. LogKit is a logging implementation. Cornerstone is a group of reusable server components and services. Phoenix is an enterprise container implementation that uses all of the other subprojects to automatically deploy and manage one or more componentized servers. Apps is a home for several Phoenix-compatible server applications and reusable components (like FtpServer).
Xindice is an open source Native XML Database. It stores and indexes compressed XML documents in order to provide that data to a client application with very little server-side processing overhead. It also provides functionality that is unique to XML data, which can't easily be reproduced by relational databases.
Tapestry is a rich, component-based object model for developing dynamic, robust, highly interactive Web applications. Applications are constructed in terms of Java objects, methods and properties, instead of URLs and query parameters. It builds and interprets all URLs, dispatching directly to application-specific "listener" methods. It includes complete source code, documentation, tutorials and a complete example J2EE application.