The ASF is made up of over 100 top level projects that cover a wide range of technologies. Chances are if you are looking for a rewarding experience in Open Source, you are going to find it here.
Component oriented framework for creating dynamic, robust, highly scalable web applications in Java.
Tapestry is a component-oriented Java web application framework. Its design emphasizes ease of use and developer productivity. Component classes are simple POJOs, with Tapestry using byte code manipulation to enhance classes at runtime. Configuration is via annotations and naming conventions rather than XML. Web page and component templates use regular (X)HTML that can be edited by any web designer. Live Class Reloading enables you to edit Java code and immediately see results by reloading the page in the web browser, resulting in a very fast "code it - see it - fix it" loop.
Apache Thrift allows you to define data types and service interfaces in a simple definition file. Taking that file as input, the compiler generates code to be used to easily build RPC clients and servers that communicate seamlessly across programming languages. Instead of writing a load of boilerplate code to serialize and transport your objects and invoke remote methods, you can get right down to business.
Provides Support for Some Archive Formats not Supported by Ant's Core
This is a library of Ant tasks and types uses Apache Commons Compress to support additional archive formats like ar, pack200, xz and cpio.