Java's full-fidelity type information, combined with its elegant class file structure, makes it easy to build proxy interfaces on the fly. Java 1.3 introduces Dynamic Proxies that automate this process by creating new classes to dynamically delegate method calls. This session demonstrates how to use Dynamic Proxies, how they build bytecode on the fly, and how to evaluate their performance. Participants will receive free source code for the Generic Delegator, an implementation of Dynamic Proxies compatible with Java 1.2 or later.

Outline

1. What are Dynamic Proxies used for?
   1. Java reflection
   2. Decorators
   3. Proxies in RMI
2. The architecture
   1. The java .class file format
   2. ClassLoaders
   3. Building bytecodes on the fly
   4. Performance
3. Implications: Other bytecode generation projects
   1. Instrumentation
   2. Performance optimization
   3. Assertions
   4. Context