View source for OCUP Interaction Diagrams

[[Category:Private]]
[[Category:OCUP]]
==Interaction⌘==
* An '''interaction''' is a unit of behavior that focuses on the visible exchange of information between participants (limited in time).
* 4 interaction diagrams in UML 2.0:
** '''Sequence diagrams''' - sequence in which messages are exchanged (OCUP Fundamental)
** '''Communication diagrams''' - relationship between the participants
** '''Timing diagrams''' - state changes of the participants relative to the time
** '''Interaction overview diagrams''' - order of interactions in an activity-like notation
==Sequence Diagram⌘==
[[File:SimpleSequenceDiagram.png]]
* Participants are represented by a rectangle and a dashed line (lifeline)
* Messages are represented by arrows between lifelines
* Time runs from top to bottom
* The entire diagram represents one interaction
===Connectable Element⌘===
[[File:Lifeline.png]]

Connectable Element
* a set of instances
* can be considered as objects of the specified type
* lifelines (participants) represent connectable elements

The header of a lifeline can also show the keyword '''self'''. 

In this case, the lifeline represents an instance of the classifier to which the interaction belongs.

===Selector⌘===
[[File:Selector.png]]
* If the '''ConnectableElement''' is multivalued (i.e, has a multiplicity > 1), then the '''Lifeline''' may have an expression (the "selector"). 
* '''Selector''' specifies which particular part is represented by this Lifeline. 
* If the selector is omitted, this means that an arbitrary representative of the multivalued ConnectableElement is chosen.

===Execution Specification (Execution Occurrence)⌘===
[[File:ExecutionSpecification.png]]
* Specification of the execution of a unit of behavior within the lifeline.
* Sending and receiving messages determine start and end of execution specification.

===Message⌘===
[[File:SequenceDiagramMessage.png]]
===Message Types⌘===
* '''Synchronous message''' (filled arrowhead):
** caller waits until called behavior terminates
** reply message represented by dashed line with open arrowhead
* '''Asynchronous message''' (open arrowhead):
** caller doesn't wait but continues after call, no reply
* '''Found message''' (open arrowhead originating from a filled circle):
** receiver known, sender not known
* '''Lost message''' (open arrowhead pointing to a filled circle)
** sender known, receiver not known
* '''Create message''' (dashed line with open arrowhead pointing to header of lifeline):
** new lifeline is created at this point in the diagram
* '''Delete message''' (open arrowhead):
** object destruction, stop (destruction of an object is represented by a cross on the lifeline)

===Event Occurrences⌘===
[[File:SequenceEventOcc.png]]
* send event is denoted by an exclamation mark ('''!p''')
* receive event is denoted by question mark ('''?p''')
* A valid sequence for the interaction: '''< !p, ?p, !q, ?q >'''
* '''It's not the only valid sequence!'''
===Event Occurrences valid trace⌘===
[[File:SequenceEventOcc2.png]]

===Event Occurrences Rule⌘===
* '''Send''' event '''before receive '''event
* The order of events along one lifeline is '''relevant'''. 
* The position of one event relative to an event on another lifeline is '''insignificant'''.

===Event Occurrences Example⌘===
[[File:SequenceEventOccExample.png]]

===General Ordering⌘===
[[File:SequenceGeneralOrdering.png]]

* relationship between two events (on different lifelines)
* one event must occur before the other in a valid trace
* Notation: a dotted line between a centre filled triangle - Triangle points to later event
{{PB}}
==Other Interaction Diagrams⌘==
* Communication Diagram
* Timing Diagram
* Interaction Overview Diagram

===Communication Diagram⌘===
[[File:CommunicationDiagram.png]]
===Timing Diagram⌘===
[[File:TimingDiagram.png]]
===Interaction Overview Diagram⌘===
[[File:InteractionOverviewDiagram.png]]

===Questions⌘===
*What is an interaction?
*What does a lifeline represent?
*What is an execution occurrence?
* What types of message are there?
* How is the semantics of an interaction defined?