Signal Activity in BPEL 11g

Signal Activity in BPEL

This activity is used in a master process to notify detail processes to perform processing at runtime and used in detail processes to notify a master process that processing has completed.

 Figure A-37 shows the Signal dialog in BPEL 1.1 and BPEL 2.0.

Figure A-37 Signal Dialog

 

                 

Read More

Sequence Activity in BPEL 11g

Sequence Activity in BPEL

This activity enables you to define a collection of activities to be performed in sequential order.

For example, you may want the following activities performed in a specific order:

·    A customer request is received in a receive activity.

·    The request is processed inside a flow activity that enables concurrent behavior.

·  A reply message with the final approval status of the request is sent back to the customer in a reply activity.

A sequence activity makes the assumption that the request can be processed in a reasonable amount of time, justifying the requirement that the invoker wait for a synchronous response (because this service is offered as a request-response operation).

When this assumption cannot be made, it is better to define the customer interaction as a pair of asynchronous message exchanges.

When you double-click the Sequence icon, the activity area shown in Figure A-36 appears. Drag and define appropriate activities inside the sequence activity.

Figure A-36 Sequence Activity

                                    

Read More

Scope Activity in BPEL 11g

Scope Activity in BPEL

This activity consists of a collection of nested activities that can have their own local variables, fault handlers, compensation handlers, and so on. A scope activity is analogous to a { } block in a programming language.

Each scope has a primary activity that defines its behavior. The primary activity can be a complex structured activity, with many nested activities within it to arbitrary depth. The scope is shared by all the nested activities.

Figure A-33 shows the Scope dialog in BPEL 1.1. Define appropriate activities inside the scope activity.

Figure A-33 Scope Dialog

                 

In BPEL 2.0, the Scope dialog includes a Documentation tab and does not include a Skip Condition tab.

Fault handling is associated with a scope activity. The goal is to undo the incomplete and unsuccessful work of a scope activity in which a fault has occurred. You define catch activities in a scope activity to create a set of custom fault-handling activities. Each catch activity is defined to intercept a specific type of fault.

Figure A-34 shows the Add Catch icon inside a scope activity. 

Figure A-35 shows the catch activity area that appears when you click the Add Catch icon. 

Within the area defined as Drop Activity Here, you drag additional activities to create fault handling logic to catch and manage exceptions.

For example, a client provides a social security number to a Credit Rating service when applying for a loan. This number is used to perform a credit check. If a bad credit history is identified or the social security number is identified as invalid, an assign activity inside the catch activity notifies the client of the loan offer rejection. The entire loan application process is terminated with a terminate activity.

Figure A-34 Creating a Catch Branch

                                           

Figure A-35 Catch Activity Icon

                              

Read More