1. Developing SOA Applications with Oracle SOA Suite
  2. Using the Human Workflow Service Component
  3. Configuring Human Tasks
  4. Specifying Java or Business Event Callbacks

Specifying Java or Business Event Callbacks

You can specify Java or business event callbacks. You can register callbacks for the workflow service to call when a particular stage is reached during the lifecycle of a task.

Note:

If you implemented a callback, then the user callback implementation overrides any other form of restricted assignment. When you perform a search, the result only shows the users that the user callback returns.

Two types of callbacks are supported:

  • Java callbacks: The callback class must implement the interface oracle.bpel.services.workflow.task.IRoutingSlipCallback. Make the callback class available in the class path of the server.

  • Business event callbacks: You can have business events raised when the state of a human task changes. You do not need to develop and register a Java class. The caller implements the callback using an Oracle Mediator service component to subscribe to the applicable business event to be informed of the current state of an approval transaction.

To specify callback classes on task status:

  1. Click the Events tab.

    The following state change callbacks are available for selection:

    • OnAssigned

      Select if the callback class must be called on any assignment change, including standard routing, reassignment, delegation, escalation, and so on. If a callback is required when a task has an outcome update (that is, one of the approvers in a chain approves or rejects the task), this option must be selected.

    • OnUpdated

      Select if the callback class must be called on any update (including payload, comments, attachments, priority, and so on).

    • OnCompleted

      Select if the callback class must finally be called when the task is completed and control is about to be passed to the initiator (such as the BPEL process initiating the task).

    • OnStageCompleted

      Select if the callback class must be called to enable business event callbacks in a human workflow task. When the event is raised, it contains the name of the completed stage, the outcome for the completed stage, and a snapshot of the task when the callback is invoked.

    • OnSubtaskUpdated

      Select if the callback class must be called on any update (including payload, comments, attachments, priority, and so on) on a subtask (one of the tasks in a parallel-and-parallel scenario).

    If your Oracle JDeveloper installation is updated to include both the BPEL and BPM extensions, then the following content callbacks are also available for selection:

    • Comments Callback

      Select if the callback class must be called to store the comments in a schema other than the WFCOMMENTS column. The callback class must implement the oracle.bpel.services.workflow.callback.NotesStore interface.

    • Attachment Call Back

      Select if the callback class must be called to store the attachments in a schema other than the WFATTACHMENT table in the soa-infra schema. The callback class must implement the oracle.bpel.services.workflow.callback.AttachmentStore interface.

    • Validation Callback

      Select if the callback class must be called to validate either the task or payload before updating, approving, and so on. The callback class must implement the oracle.bpel.services.workflow.task.ITaskValidationCallback interface.

  2. See the following section based on the type of callback to perform.