To begin work on a task, we use either @StartTask or @BeginTask on the listener method:

@StartTask
public String start() { ... }

Alternatively we can begin work on a task using pages.xml:

<page>
    <start-task />
</page>

These annotations begin a special kind of conversation that has significance in terms of the overarching business process. Work done by this conversation has access to state held in the business process context.

If we end the conversation using @EndTask, Seam will signal the completion of the task:

@EndTask(transition="completed")
public String completed() { ... }

Alternatively we can use pages.xml:

<page>
    <end-task transition="completed" />
</page>

(Alternatively, we could have used <end-conversation> as shown above.)

At this point, jBPM takes over and continues executing the business process definition. (In more complex processes, several tasks might need to be completed before process execution can resume.)

Please refer to the jBPM documentation for a more thorough overview of the sophisticated features that jBPM provides for managing complex business processes.