HotWave: creating adaptive tools with dynamic aspect-oriented programming in Java

Developing tools for profiling, debugging, testing, and reverse engineering is error-prone, time-consuming, and therefore costly when using low-level techniques, such as bytecode instrumentation. As a solution to these problems, we promote tool development in Java using high-level aspect-oriented programming (AOP). We demonstrate that the use of aspects yields compact tools that are easy to develop and extend. As enabling technology, we rely on HotWave, a new tool for dynamic and comprehensive aspect weaving. HotWave reconciles compatibility with existing virtual machine and AOP technologies. It provides support for runtime adaptation of aspects and reweaving of previously loaded code, as well as the ability to weave aspects into all methods executing in a Java Virtual Machine, including methods in the standard Java class library. HotWave also features a new mechanism for efficiently passing data between advices that are woven into the same method. We demonstrate the benefits of HotWave's distinguishing features with two case studies in the area of profiling.