A study on exception detection and handling using aspect-oriented programming

Aspect oriented programming (AOP) is intended to ease situations that involve many kinds of code tangling. The paper reports on a study to investigate AOP's ability to ease tangling related to exception detection and handling. We took an existing framework written in Java/sup TM/, the JWAM framework, and partially reengineered its exception detection and handling aspects using AspectJ/sup TM/, an aspect oriented programming extension to Java. We found that AspectJ supported implementations that drastically reduced the portion of the code related to exception detection and handling. In one scenario, we were able to reduce that code by a factor of 4. We also found that, with respect to the original implementation in plain Java, AspectJ provided better support for different configurations of exceptional behaviors, more tolerance for changes in the specifications of exceptional behaviors, better support for incremental development, better reuse, automatic enforcement of contracts in applications that use the framework, and cleaner program texts. We also found some weaknesses of AspectJ that should be addressed in the future.