Bounded and Unbounded Task Flows

Unbounded
A specialized form of task flow that has a single entry point and zero or more exit points. It is configured in adfc-config.xml file.

• It cannot declaratively specify parameters.
• It contains default activity
• It cannot be called by another task flow.

Unbounded task flow can be used when

• You want to take advantage of ADF controller features not offered by bounded task flows
• You don’t need ADF controller features that are offered when using a bounded task flow.
• The task flow will not be called by another task flow.
• The application has multiple points of entry.

Bounded
A set of activities, control flow rules and managed beans that interact to allow a user to complete a task. It is used to encapsulate a reusable portion of an application.

• A bounded task flow can be called another bounded task flow or unbounded task flow.
• The bounded task flow always specifies a default activity
• Managed bean specified in pageFlow scope is visible only within the task flow, and isolated from rest of application.

Because of the resuability features, bounded task is mostly used in all applications.


Features of Bounded Task Flow

1. Well-defined boundary An ADF bounded task flow consists of its own set of private control flow rules, activities and managed beans. Input and Ouput parameters are available to bounded task flow just like a function call. Data controls can be shared between task flows.
2. Single point of entry An ADF bounded task flow has a default activity that executes before all other activities in the task flow.
3. PageFlow memory scope Its a new scope introduced in ADF. And its lifespan is ADF bounded task flow.
4. Reuse You can identify an entire group of activities as a single entity and reuse it in another application.
5. Parameters and return values You can pass the parameters and get the output just like a function call.
6. Transaction ManagementIt represents a transactional unit of work. While entering a bounded task flow you can create new transaction or join the existing one.
7. Reentry You can choose to reenter the bounded task flow.
8. Security Secure a bounded task flow using fusion security.