Lifecycle of stand-alone human tasks that are invoked by a BPEL process

The lifecycle of an inline task is always managed by its associated BPEL process. The lifecycle of a stand-alone to-do task can be managed by the calling BPEL process depending on the definition of the task.

For reuse, it often makes sense to implement a step of the business logic as a separate stand-alone task and to invoke this task from different locations in the main process. When these applications are deployed, the stand-alone task must be deployed to the same Business Process Choreographer database.

A stand-alone to-do task can have a peer-to-peer relationship or a parent-child relationship with the calling process. This relationship determines how the lifecycle of the invoked task is managed.

The process-task relationship is determined by the autonomy attribute of the task. This attribute can have one of the following values:

Peer

If the task has a peer-to-peer relationship with the BPEL process, the lifecycle of the task is independent of the BPEL process.

Child

If the task has a parent-child relationship with the BPEL process, some lifecycle operations on the process instance are also applied to the task instance. These operations are delete and terminate.

In addition, the following lifecycle operations on the calling invoke activity are also applied to the task instance:

Restarting an invoke activity causes the current task instance to be deleted, and a new task instance to be created and started.
Forcing completion of the invoke activity causes the task instance to be terminated.
Skipping the invoke activity in the running state causes the task instance to be terminated.
Deleting or terminating the invoke activity causes the task instance to be deleted.

If the autonomy attribute of the task is set to child, you can still suspend and resume the task instance independently of the BPEL process.

A parent-child relationship can be established only between processes and tasks that interact directly. If another SCA component intercepts this interaction, it might prevent a parent-child relationship from being established, for example, an interface map component that is wired between the process and the task.