About Transition Exceptions

The following transition types can generate exceptions:

Join Timeout transition

Step Iterations Exceeded transition

Unsatisfied Join transition

A transition from a Boundary Timer Event

Any transition that generates an exception contains a top-level document named ExceptionTransition. This document can contain up to four fields:

ExceptionType. Contains one of the following values indicating the type of exception that caused the error: StepTimeout, JoinTimeout, RetriesExceeded, or UnsatisfiedJoin. ProcessTimeout, StepError, and Cancel values are also supported for those exceptions.

SourceStep. Contains the step ID of the step if there is one. No value is provided for exceptions of type ProcessTimeout or Cancel.

SourceStepIteration. The step iteration count of the step that encountered the error.

ErrorMessage. Contains the error message when the exception type is StepError.

The information in this document enables you to create specialized logic for handling step and process errors. For more information, see pub.prt.ExceptionTransitionInfo.

Process timeouts and process cancellations also generate an exception specific to each condition. Although these transitions in are not represented by a graphical transition line in a process model, the exceptions they generate are passed to the process timeout handler and process cancel handler steps, respectively.