Architecture Modeling - SPES 2020

3.3.1.1 Ports
Architecture Modeling
Ports are the interaction points of a component. The set of all ports of a component constitutes
its syntactical interface. Figure 3.24 depicts how the port concept is embedded in
the architecture meta-model. Each Port of a component has a name and is typed by a
PortSpecification, which declares the Flows or Services required or provided at
some port. A flow is a data-oriented interaction point and services model services a component
provides or requires. The PortSpecification is either a set of flows or a set of services,
but not both.
Port
+ isConjugated: Boolean
+port
+component
1
RichComponent
FlowDirection
in
out
bidirectional
0..*
FlowKind
discrete
continuous
event
+portSpecification
+type
PortSpecification
0..*
InteractionPoint
«isOfType» 1
1
+interactionPoint
Flow
+ direction: FlowDirection
+ kind: FlowKind
Serv iceDirection
provided
required
«isOfType» 1
Serv ice
+ direction: ServiceDirection
«isOfType»
+returnType 1
+type
DataType
+type
+service
0..1
1 «isOfType»
Figure 3.24: Meta-model integration of the concept of Ports
0..*
Parameter
+formalParameter
Flows have a name, a direction (in, out or bidirectional) and are typed by a
DataType. The DataType concept is explained in [50] and is out of the scope of this document.
A flow declares the kind of a data-exchange of an owning component. Along with the
DataType and direction, its kind can be specified, which is either event, discrete or
continuous (see Figure 3.25). Declaring an event flow means there is a value available on
the flow only at certain time instants and the value can change from instant to instant. In a
discrete flow the value is always available, even between the time instants at which the value
changes. In a continuous flow there is also always a value available, but it can evolve continuously
during time durations and also change discretely at time instants. The trajectory of a
continuous flow can be described by a piecewise continuous function.
val
event
t
val
discrete
Figure 3.25: The different kinds of flows
t
val
continuous
Services have a name and a direction (provided or required). A Service is typed by
multiple DataTypes, that constitute the signature of the service. As shown in Figure 3.24 a
service owns a set of DataTypes, that define the parameters of the service and a DataType
in the role of returnType, that defines the return value of the service declaration.
t
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