Inline tasks are an integral part of the BPEL process.
Inline tasks can be to-do tasks, invocation tasks, or administration
tasks. Because collaboration tasks leverage the interaction between
people and do not directly interact with processes, they cannot be
inline tasks. Inline tasks are neither visible as SCA components (cannot
be wired), nor are they reusable in other processes or activities.
Inline tasks have access to the process context, such as process
variables, custom properties, and activity data. This can be useful
for tasks that involve the separation of duties. Inline to-do tasks
can emit their CEI and audit log events as business process activity
events and human task events. Their subtasks and follow-on tasks emit
events as human task events.
The following rules apply to inline tasks:
- To-do tasks are human task activities in a process. They share
the same state, but the human task activity does not reflect the forwarded
state or the task substates.
- Invocation tasks are associated with receive or pick (receive
choice) activities, or on-event event handlers.
- Administration tasks are attached either to the process, or to
an activity in the process.
- The life cycle is usually determined by the process.
- To-do tasks and administration tasks are created by the BPEL process, and deleted with the process.
- Inline to-do tasks do not have their own expiration,
the expiration is defined on the corresponding human task activity.
When the human task activity expires, the to-do task is terminated.
Updating or rescheduling of inline to-do tasks is supported by both
the Human Task Manager and Business Flow Manager APIs. If the Human
Task Manager API is used, the request is forwarded to the human task
activity.
- If
invocation tasks are created and started by the BPEL process,
their life cycle is determined by the process, and they are deleted
with the process. If they are started using the Human Task Manager
API, their life cycle is independent of the process regardless of
how they were created, and their results can be displayed even after
the process is deleted.
- Instances of inline human tasks can be migrated with the process
instance they are related to.
- Inline
invocation tasks can be modeled with values for both the duration
until expiration and the duration until deletion. These settings are
available only if the tasks are created using the Human Task Manager
API. These durations can be updated before the task starts, and rescheduled
after the task has started.
- The update action on inline tasks supports only
a subset of task properties. Only task properties that have no representation
in the process or activity can be updated. For more information on
the update method, see the Javadoc API documentation
for the HumanTaskManager interface in the com.ibm.task.api package,
and the information on which roles are authorized to make specific
update actions on tasks.
Inline
tasks are used for process authorization:
- The roles reader, administrator, potential owner, owner, and editor
of a to-do task are identical to the corresponding roles of the human
task activity in the process.
- The potential starter role of an inline invocation task determines
who is allowed to invoke and send messages to the corresponding receive
or pick (receive choice) activity, or on-event event handler. Note
that the potential starter and potential instance creator roles have
identical people assignments. If an inline invocation task is not
defined, everybody is authorized to start the activity or event handler.
- The administrator and reader roles for a process administration
task determine who is the process administrator or the process reader.
The process administrator can, for example, force terminate the process
instance.
- The administrator role for an activity administration task determines
who is allowed to administer the corresponding activity. The activity
administrator and the process administrator can, for example, force
retry the activity.
- The process reader and process administrator authorization are
inherited by every process activity or inline human task.
- The scope reader and the scope administrator authorization is
inherited by all of the activities in the scope.
Note: If you are using one of the alternative
process administration modes, administration tasks might not be created.
In addition, administrative actions on processes, scopes, and activities
might be limited to users in the BPESystemAdministrator role. For
more information about alternative administration modes, see Alternative administration modes for BPEL processes.