Components and semantics

1
Components and semantics

• Computer Science at Karlstad University welcomes
  the Mälardalen Real-time Research Center, Västerås

2
Basic interface model, UML 1.4
Clientcomponent
Suppliercomponent
ltltimplementsgtgt
ltltrequiresgtgt
Specify client and supplier interfaces together
3
Revised interface model, UML 2.0
Clientcomponent
Suppliercomponent
ltltrequiresgtgt
ltltoffersgtgt
Specify client and supplier interfaces separately
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Version and purchase management
Clientcomponent
Suppliercomponent
ltltrequiresgtgt
ltltoffersgtgt
Clientcomponent
Suppliercomponent
ltltrequiresgtgt
ltltoffersgtgt
Clientcomponent
Suppliercomponent
ltltrequiresgtgt
ltltoffersgtgt
One to one check between client and supplier
n2checks
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Interface model needed?
Clientcomponent
Suppliercomponent
ltltrequiresgtgt
ltltoffersgtgt

• Evaluate client and supplier interfaces relative
  to systems requirements

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Version and purchase management
Clientcomponent
Suppliercomponent
ltltrequiresgtgt
ltltoffersgtgt
Clientcomponent
Suppliercomponent
ltltrequiresgtgt
ltltoffersgtgt
Clientcomponent
Suppliercomponent
ltltrequiresgtgt
ltltoffersgtgt
Each client and supplier checked separately
against the system requirements 2n checks
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Relating interfaces to each other
Inheritance
Version control
Component purchase
Clientcomponent
Baseclass
VersionA
time
Derivedclass
VersionB
Suppliercomponent

• Works as long as the lower interface contracts
  define subtypes of (are equal to or weaker
  than) the upper ones