Satya Komatineni shows how to build a framework to distribute events to one or more handlers, allowing for flexible, pluggable applications.
Edward Lineberry shows you how to get started developing BlackBerry-specific J2ME applications.
Webwork is a web application framework designed for simplicity and productivity. In this introduction, Zarar Siddiqi introduces the options for validating web forms in WebWork, including using its built-in validators and defining your own.
This "stupid question" is about the >>, >>>, and ?: operators--what do they do and when are they used?
Jason Zhicheng Li introduces the State Machine Compiler, which lets you create a state machine with markup and separate your state transition logic from your other business logic.
Diego Naya offers an introduction to OSWorkflow, an open source workflow engine written entirely in Java.
Lu Jian shows how the JMXRemote project allows you to register local MBeans with a remote MBean server, something not supported in a typical JMX setup.
Mohan Radhakrishnan shows how to bring mixins to Java by employing aspect-oriented programming techniques.
Jeff Friesen introduces an algorithm for creating an "embossed" effect for images, and then shows how to implement it in Java2D and Swing.