Redland is a set of C libraries providing a high-level API for the Resource Description Framework (RDF), allowing it to be stored, parsed, serialized, queried, and manipulated. It has an object-based, modular design and comes with detailed reference documentation and examples. Redland supports all RDF vocabularies such as FOAF, RSS 1.0, Dublin Core, DOAP, and OWL, the query languages SPARQL and RDQL, and all RDF syntaxes including Turtle, RDF/XML, RDF/JSON, RSS, Atom, RDFa, and GRDDL.
Luxor is an open-source XML User Interface Language (XUL) toolkit in Java that lets you build UIs using XML and also includes an ultra light-weight, multi-threaded Web server, a portal engine, and a template engine. It is also Web Start-ready, as everything fits in a jar and requires no loose files.
OpenEJB is a simple, lightweight Enterprise JavaBeans (EJB) container and server. You can embed OpenEJB in your own applications, or in a Web application server like Tomcat, or run it as a standalone EJB server. It supports EJB 3.0, 2.1, 2.0, and 1.1, and has partial support for EJB 3.1.
WidgetServer is a Java/XML server-side GUI-framework which enables an application to run as either a monolithic Swing app, a client/server Swing app, or as a Web app without any change and without loss of functionality. An Eclipse Plugin is available as well. A rich widget set is supported that includes tree views, tabbed panes, split panels, and much more. Animations, all types of events, and several effects are supported, as well. A unified widget-based, object-oriented programming interface for Web and Swing GUIs is offered to the developer to control and assemble the GUI. Web applications are fully AJAX enabled. For Swing client/server applications, the framework handles client/server communication, including compression and security layers.
Studs MVC Framework+ contains a port of Apache's Jakarta Struts to PHP, though the libraries included in the rest of the project are much more vast. In order to implement the Struts port, it was necessary to build a core, object-oriented API in the style of the JDK and the Jakarta Commons, a servlet container to handle HTTP requests and to invoke servlet classes, and finally, a parsing engine for JSP-style template pages. In the end, the result is an environment which is very similar to that provided by a J2EE Web Container, only everything is implemented in PHP. While it was possible to carry over many of the concepts, designs and mechanisms from J2EE, some limitations do exist due to the nature of the PHP programming language, such as the lack of checked exceptions (runtime only).
Spring is a lightweight Java/J2EE application framework based on code published in "Expert One-on-One J2EE Design and Development" by Rod Johnson. It includes powerful JavaBeans-based configuration management applying Inversion-of-Control principles, a generic abstraction layer for transaction management allowing for pluggable transaction managers, a JDBC abstraction layer, integration with Hibernate, JDO, Apache OJB, and iBATIS SQL Maps, AOP functionality, and a flexible MVC Web application framework with multiple view technologies. There is also a .NET port available.