A pattern with a closed XOR rule starts with a function at which a decision must be made and that is followed by an XOR rule. Each of the various branches must start with an event.
You can define conditions that have their own business semantics and specify which branch is to be taken after the XOR. The conditions can be specified as follows:
The Condition expression attribute is specified at the connection leading from the XOR rule to the subsequent event.
The Connection role attribute is specified at the connection leading from the XOR rule to the subsequent event.
The Name attribute is specified for the event that follows the XOR rule.
In the BPMN diagram, the joining XOR pattern is transformed into a task that requires a decision and is followed by a data-based XOR gateway.
The Condition expression attribute specified in the EPC (see graphic) is transformed into the Condition expression attribute of the connection that starts at the XOR gateway. In addition, the Condition attribute is set to the value Expression. The graphic displays an example with two branches, but any number of branches can be modeled.
Branches that only contain events are grouped together in a single branch in the BPMN diagram. The conditions are combined in such a way that each condition generates a separate line in the Condition expression attribute of the connection.