Research on Exception Handling Mechanism Based on Directed Graph in Service Composition

摘要

To enforce consistency and reliability of web services composite at run-time, solving exception is to ensure the transaction atomicity anomalies, it is an effective method. This paper proposes a novel mechanism based on directed graph to addressing the problem of exception handling in web services composite. According to execution dependencies and compensation dependencies among tasks in business processes, adopt the approach of directed graph to set up functional model, when exceptions are handled with forward or backward-recovery methods during execution of business processes, the approach can guarantee compensation achieving, and also gives consideration to the problem that there are no compensation services or the cost to achieve compensation, it is too expensive. Simulations prove that when the approach can efficiently guarantee the consistency and reliability of composite services at run-time.