Call activity and subprocess steps can be configured to loop. Looping means to repeatedly run the steps within the top-level call activity or subprocess step.

Call activities (BPMN Call Activity steps and webMethods Referenced Process (Deprecated) steps) and subprocesses (BPMN Subprocess steps and webMethods Subprocess (Deprecated) steps) support standard loops. Standard loops are configured on the Loops tab in the Properties view of the step.

The Trace view displays Loop Iteration information for looped call activities (BPMN Call Activity steps and webMethods Referenced Process (Deprecated) steps) and BPMN Subprocess steps.

webMethods Subprocess (Deprecated) steps, though configured the same way, do not loop the same way. They are displayed differently in webMethods Monitor and in the Trace view. The difference is that the loop count, represented in the Loop Iterations field for other looped steps, is represented in the Step Iteration column instead. Another difference is that you can set a breakpoint on a webMethods Subprocess (Deprecated) step and step over (execute) the loop one iteration at a time. For the other looped steps, you can debug internal steps by setting a breakpoint on an internal step, not on the parent step.

Step iterations are also counted in transition looping, called sequence flow looping in BPMN. This kind of looping involves using multiple steps and transitions to achieve a looped structure. Use standard looping for a single looped step configuration. For more information, refer to About Transition Looping.

Finally, a step iteration can also represent a step Retry Count, which is configurable on the Implementation tab in the Properties view. See About Retries.

You can use breakpoints to help debug looped call activities and BPMN subprocesses. For example, you can set a breakpoint inside of a BPMN Subprocess (not on the subprocess step itself). When you reach the breakpoint, the process debugger opens the BPMN Subprocess and stops there. You can then click Run/Resume to loop around once and stop at that breakpoint again. Finally, from the inside of a looped BPMN Subprocess step, click Step Out to complete all remaining iterations of the loop and stop at the next step.

webMethods Monitor supports tree displays for looped call activities (BPMN Call Activity and webMethods Referenced Process (Deprecated)) and BPMN Subprocesses. Monitor displays a flat list for a looped webMethods Subprocess (Deprecated) step.

As you debug a looped step and execute the steps inside the loop multiple times, the Trace view displays each step and iteration separately. The process debugger opens a looped call activity step in a new process editor tab and displays its own Trace view.

When you debug a process with a looped step, the process debugger marks the transitions with a bold line the first time through the loop, leaving the transition lines bold until the loop has completed all its loop iterations.