Chapter 10. Creating parallel processes 261
Figure 10-11 Completed process instance
4. If a problem occurs such as a block never completes execution, you can click
on the block to view which activity is causing the problem. You can terminate
or force complete troublesome activities using the Process Web Client.
5. To remove a process instance from the database and the Process Web
Client, select the instance and click Delete.
10.5 WebSphere MQ Workflow guidelines
This section describes how to implement the Parallel Process pattern to create a
process that meets the requirements set by the ITSO Electronics business
process model. It uses the Runtime pattern and Product mappings for
WebSphere MQ Workflow described in “Parallel Process Product mappings” on
page 98.
Note: You can only view a process instance in a Finished state in the Process
Web Client if the Delete Process on Completion option is turned off in the
process template. (This is set in the Server pane of the process editor.)
262 Patterns: Serial and Parallel Processes
You can download the completed process and run it in WebSphere MQ Workflow
or view it in WebSphere Business Integration Workbench. See “Sample
scenarios setup” on page 398.
10.5.1 Design guidelines
This section discusses WebSphere MQ Workflow-specific design guidelines
when creating a process that conforms to the Parallel Process pattern. The
design decisions identified in the previous chapter are also relevant here.
Process overview
This process meets the business objectives of ITSO Electronics as defined in
“Stage One: Internal ordering on demand” on page 110. The completed process
is shown in Figure 10-12.
Figure 10-12 Parallel process overview
The process has the following characteristics:
򐂰 Parallel execution
򐂰 Contains only automated activities
The process shares many characteristics with the previous scenario (the serial
process). This scenario shares the following:
򐂰 The organizational structure
򐂰 The process interface
򐂰 The data structures
򐂰 The Web services implementations
Chapter 10. Creating parallel processes 263
Parallel execution paths
The WebSphere MQ Workflow runtime supports multiple paths of execution
running in parallel. Two options are provided when the parallel execution paths
rejoin:
򐂰 Continue processing when all parallel paths have completed
򐂰 Continue processing when the first parallel execution path has completed
For this scenario, we will retrieve the delivery days from both wholesalers in
parallel. We require both paths to complete before continuing the process.
10.5.2 Development guidelines
This section describes how to build a Parallel Process pattern implementation for
ITSO Electronics. This process is essentially the same as the process built in the
previous scenario, with the addition of parallel execution paths. You should have
completed the serial process described in the previous chapter before following
the steps in this section.
Building the process
This section describes how to build the parallel process. Many of the steps are
identical to the previous chapter and are therefore not repeated here. You will
continue to use the repository data already defined in the previous scenario.
1. Open the organization created in the previous chapter in the WebSphere
Business Integration Workbench.
2. Create a new process. Switch the editing mode to Integration mode, then
open the process properties (Process
Info). In the Info window, set the
following:
a. Set the Process name and MQ Workflow process name to
ParallelProcess.
b. Set the Input structure to OrderInput and the Output structure to
OrderOutput.
c. Set Keep Finished Process to Forever.
3. Use the ADF toolbar and Repository data to model the process as shown in
Figure 10-12 on page 262. Refer to the previous chapter for information about
how to define the tasks and data mappings.
4. The first NOOP task must be set to ensure that the tasks getDeliveryDaysA
and getDeliveryDaysB are completed before processing continues. Open the
NOOP task properties, and select the Automation tab. Ensure that the task
waits for both incoming control connectors by setting Automated Execution
Wait for to All Inputs (as shown in Figure 10-13 on page 264).

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