ONJava.com: Internals of Java Class Loading
ONJava.com has published an article on the Internals of Java Class Loading. The article details what happens when classes get loaded into the JVM and how and why to create your own custom class loader. The three page article is quite detailed and goes into a fair bit of depth concerning the way that the various Java class loaders work. The article is definitely written for intermediate to advanced Java developers, but anyone with any level of Java expertise will get something useful out of it.