Table 10.91 – Boundary Event attributes

Table 10.92 specifies whether the cancel Activity attribute can be set on a boundary Event depending on the

EventDefinition it catches.

Table 10.92 – Possible Values of the cancelActivity Attribute

Activity Boundary Connections

An Intermediate Event can be attached to the boundary of an Activity under the following conditions: (One or more) Intermediate Events MAY be attached directly to the boundary of an Activity.

To be attached to the boundary of an Activity, an Intermediate Event MUST be one of the following triggers (EventDefinition): Message, Timer, Error, Escalation, Cancel, Compensation, Conditional, Signal, Multiple, and Parallel Multiple.

An Intermediate Event with a Cancel trigger MAY be attached to a Sub-Process boundary only if the Transaction attribute of the Sub-Process is set to true.

Sequence Flow Connections

See “Sequence Flow Connections Rules” on page 40 for the entire set of objects and how they MAY be a source or target of a Sequence Flow.

If the Intermediate Event is attached to the boundary of an Activity:

The Intermediate Event MUST NOT be a target for a Sequence Flow; it cannot have an incoming

Sequence Flows.

The Intermediate Event MUST be a source for a Sequence Flow.

Multiple Sequence Flows MAY originate from an Intermediate Event. For each Sequence Flow that has the Intermediate Event as a source, a new parallel path SHALL be generated.

An exception to this: an Intermediate Event with a Compensation trigger MUST NOT have an outgoing Sequence Flow (it MAY have an outgoing Association).

The Intermediate Events with the following triggers (EventDefinition) MAY be used in normal flow:

None, Message, Timer, Escalation, Compensation, Conditional, Link, Signal, Multiple, and

ParallelMultiple. Thus, the following MUST NOT: Cancel and Error. If the Intermediate Event is used within normal flow:

Intermediate Events MUST be a target of a Sequence Flow.

NOTE: This is a change from BPMN 1.2 semantics, which allowed some Intermediate Events to not have an incoming

Sequence Flow.

An Intermediate Event MAY have multiple incoming Sequence Flows.

NOTE: If the Event has multiple incoming Sequence Flows, then this is considered uncontrolled flow. This means that when a token arrives from one of the Paths, the Event will be enabled (to catch or throw). It will not wait for the arrival of tokens from the other paths. If another token arrives from the same path or another path, then a separate instance of the Event will be created. If the flow needs to be controlled, then the flow should converge with a Gateway that precedes the Event (see page 286 for more information on Gateways).

An Intermediate Event MUST be a source for a Sequence Flow.

Multiple Sequence Flows MAY originate from an Intermediate Event. For each Sequence Flow that has the Intermediate Event as a source, a new parallel path SHALL be generated.

An exception to this: a source Link Intermediate Event (as defined below), it is NOT REQUIRED to have an outgoing Sequence Flow.

A Link Intermediate Event MUST NOT be both a target and a source of a Sequence Flow.

To define the use of a Link Intermediate Event as an “Off-Page Connector” or a “Go To” object:

A Link Intermediate Event MAY be the target (target Link) or a source (source Link) of a Sequence Flow, but MUST NOT be both a target and a source.

If there is a source Link, there MUST be a matching target Link (they have the same name). There MAY be multiple source Links for a single target Link.

There MUST NOT be multiple target Links for a single source Link.

Message Flow Connections

See “Message Flow Connection Rules” on page 41 for the entire set of objects and how they MAY be a source or target of a Message Flow.