Design & Implementation Of Instrument Module In Open Source J2SE

Java Technology^TM, with its versatility, efficiency, platform portability, and security, has become the most popular technology all over the world. Project Harmony was founded by Apache as Java developers require an open-source J2SE platform to improve the Java Technology^TM. The aim of this project is to implement a compatible, independent implementation of the Java SE 5 JDK under the Apache License v2.My research work is part of this project which focuses on the design and implementation of Instrument module.Bytecode instrumentation is a technique that's applicable to solving problems in various application domains. .It can be used to enhance a program temporarily to trace its execution, gather profiling data, monitor memory usage etc, but also to change the functionality of an application in the field of aspect-oriented programming.But bytecode instrumentation tools are hard to implement because there is no standard instrumentation interface in Java Class Library. My research work focuses on design and implement instrument module to provide this interface.By using the functionality supplied by the Instrument module, user could not only change the class at load time, but also monitor the running situation of the program and offer a great ease of development of performance analysis tools, code coverage tools and AOP tools.In this paper, the whole architecture of this open-source J2SE project is presented in chapter 2; then the specifics of Java bytecode instrumentation is covered in chapter 3, and the design and implementation of the instrument module is presented in detail, with explanation of some key technologies in chapter 4 and 5.