DecisionNode extends ActivityNode, ConditionEdgeDestination, DataFlowEdgeDestination, ExecutionEdgeDestination, ExecutionEdgesSource, NamedElement

Based on its name, considers the incoming Conditions or DataFlowEdges, and follows passing or failing ExecutionEdges as appropriate.

A DecisionNode can be used to control the flow of execution within a particular operation, and accepts any number of incoming DataFlowEdges and Conditions, depending on the type of DecisionNode. A DecisionNode must have at least one failure edge and one success edge.

An ActivityOperation may contain any number of DecisionNodes. When the execution flow arrives at a DecisionNode, all incoming edges are passed to the particular node, and the decision is evaluated as either true or false. If the DecisionNode is considered to be false, the execution flow will follow all outgoing failure edges sequentially. If the DecisionNode is considered to be true, the execution flow will follow all outgoing success edges sequentially.

The DecisionNode element is based on the UML DecisionNode model element.

true?

A DecisionNode named "true?" accepts any number of incoming DataFlowEdges. This node is true if and only if all incoming values can be cast to the boolean type, and are all considered true through logical conjunction.

equal?

A DecisionNode named "equal?" accepts any number of incoming DataFlowEdges. This node is true if and only if all incoming values can be cast to the string type, and all string -cast representations can be considered equal in terms of the fn:codepoint-equal XQueryFunction.

can cast?

A DecisionNode named "can cast?" accepts one incoming DataFlowEdge (source), and has one outgoing DataFlowEdge (target). This node is true if and only if the current instance from the source edge can be successfully casted to the data type specified by the target edge, as discussed in CastNode.

[DecisionNode.html]

Implementation Notes

A DecisionNode named 'failed?' will return true ifthe incoming CastNode (through a DataFlowEdge) couldnot be cast correctly. [CanCastCondition]
A DecisionNode named 'failed?' will return true ifthe incoming CastNode (through a DataFlowEdge) couldnot be cast correctly. [CanCastCondition]
For a DecisionNode named 'true?', if more than one Condition is incoming to an executed DecisionNode, then all incoming Conditions must be true for execution to pass. [Contents]
For a DecisionNode named 'true?', if no Conditions are incoming to a DecisionNode, then execution will ignore the pass/fail outgoing edges. [Contents]
The 'is set?' DecisionNode only supports incoming Values as parameters. [DataFlow]

Constraints

"A 'can cast?' DecisionNode needs to have an incoming DataFlowEdge from a CastNode" [Checks.chk]

"A compare DecisionNode must have at least two data flows in to compare" [Checks.chk]

"A DecisionNode can only have at most two out execution edges" [Checks.chk]

Inherited Attributes

generatedRule : EString (optional)

To assist in debugging, this attribute may be populated with the name of the model completion rule that created this element. More extensive traceability support may be provided in the future.

id : EString (optional)

A unique identifier for this model element. Should be globally unique.

isGenerated : EBoolean (optional)

Set to true if the current element has been generated.

name : EString (optional)

A non-unique string that names a given object.

Inherited References