AbstractActions model either a service’s internal computations or calls to external (i.e., required) services, or describe some form of control flow alteration (i.e., branching, loop, or fork). The following first clarifies the notions of internal and external actions, whose meta-classes both inherit from AbstractAction.
The RDSEFF defines the control flow between internal and external actions with the predecessor/successor relationship between AbstractActions to model sequential executions. Additionally, special actions for branching, loops, and forks allow other kinds of control flow. Other than flowcharts or UML activity diagrams, the RDSEFF language (as well as the usage model language) requires developers to make the branching, loop, fork bodies explicit using nested ResourceDemandingBehaviours. It disallows backward references in the chain of AbstractActions, which are basically
goto statements and can lead to ambiguities and difficult maintainability. For example, this might lead to intertwined control flows as in the example in Fig. 4.9(a), where both the sequences ’abcabcdbcd’ and ’abcdbcabcd’ could be occur if each backward reference is executed once, which might lead to different execution times. Backward references also allow the specification of loops with multiple entry points as in Fig. 4.9(b). This is not desirable, as the number of loop iterations cannot be specified directly in these cases, which is however necessary for accurate performance prediction. If a developer would specify that each backward link in Fig. 4.9(b) is executed only once, both sequences ’ababc’ and ’abcababc’ would be possible although they would have different execution times, as ’a’ is executed three times in the latter case. To avoid such ambiguities, control flow in the PCM RDSEFF and usage model must be specified without backward references in the chain of AbstractActions. Branches, loops, forks, and their respective bodies have to be made explicit in the specification using nested ResourceDemandingBehaviours.

Attribute
<Class> AbstractAction	predecessor_AbstractAction
<Class> AbstractAction	successor_AbstractAction

!!TableHeading.InheritedAttributes!! samm::core::Entity

documentation

!!TableHeading.InheritedAttributes!! samm::core::NamedEntity

name

!!TableHeading.InheritedAttributes!! identifier::Identifier

id

!!TableHeading.InheritedOperations!! samm::core::Entity

!!TableHeading.InheritedOperations!! samm::core::NamedEntity

!!TableHeading.InheritedOperations!! identifier::Identifier

 predecessor_AbstractAction

Public <Class> AbstractAction predecessor_AbstractAction

Eigenschaften:

Aggregation	None
Alias
Association	<Association> transition
Association End
Class	<Class> AbstractAction
Datatype
Default
Default Value
Is Composite	false
Is Derived	false
Is Derived Union	false
Is Leaf	false
Is Ordered	false
Is Read Only	false
Is Static	false
Is Unique	true
Keywords
Lower	0
Lower Value	<Literal Integer> 0
Multiplicity	0..1
Name	predecessor_AbstractAction
Name Expression
Namespace	<Class> AbstractAction
Opposite	<Property> successor_AbstractAction : AbstractAction [0..1]
Owned Template Signature
Owner	<Class> AbstractAction
Owning Association
Owning Template Parameter
Qualified Name	seff::AbstractAction::predecessor_AbstractAction
Stereotype
Template Parameter
Type	<Class> AbstractAction
Upper	1
Upper Value	<Literal Unlimited Natural> 1
Visibility	Public

 successor_AbstractAction

Public <Class> AbstractAction successor_AbstractAction

Eigenschaften:

Aggregation	None
Alias
Association	<Association> transition
Association End
Class	<Class> AbstractAction
Datatype
Default
Default Value
Is Composite	false
Is Derived	false
Is Derived Union	false
Is Leaf	false
Is Ordered	false
Is Read Only	false
Is Static	false
Is Unique	true
Keywords
Lower	0
Lower Value	<Literal Integer> 0
Multiplicity	0..1
Name	successor_AbstractAction
Name Expression
Namespace	<Class> AbstractAction
Opposite	<Property> predecessor_AbstractAction : AbstractAction [0..1]
Owned Template Signature
Owner	<Class> AbstractAction
Owning Association
Owning Template Parameter
Qualified Name	seff::AbstractAction::successor_AbstractAction
Stereotype
Template Parameter
Type	<Class> AbstractAction
Upper	1
Upper Value	<Literal Unlimited Natural> 1
Visibility	Public