Research of Human Task Performing System Based on Asynchronous Pattern in BPEL

BPEL(Business Process Execution Language) is a kind of language which can be used to write automated business process,but it doesn't support user interactions.User interactions can be achieved by human tasks.Therefore,an architecture which supports the performing of the human task in BPEL was proposed.There is a human task mana-ger outside of the engine to maintain human activities.BPEL processes interact with the human task manager with asynchronous pattern,which adapts to the feature of time uncertainty of the human task.The message correlation set in BPEL is used to correlate the invoking activity and the waiting activity during the period of asynchronous invocation.