Object Models and Their Types


Object Models

Object models are the models that describe the system in terms of object classes and their associations.

  • An object class is an abstraction over a set of objects with common attributes and the services provided by each object.
  • Natural ways of reflecting the real-world entities manipulated by the system.
  • More abstract entities are more difficult to model using this approach.
  • Object classes reflecting domain entities are reusable across systems.

Various object models may be produced as:Object Models

 


1 Inheritance Model

  • Organizes the domain object classes into a hierarchy.
  • Classes at the top of the hierarchy reflect the common features of all classes.
  • Object classes inherit their attributes and services from one or more super-classes.
  • Class hierarchy design can be a difficult process if duplication in different branches is to be avoided.Object Models

Fig: Library class hierarchy as Inheritance Model


2 Aggregation Model

  • An aggregation model shows how classes that are collections are composed of other classes.
  • Aggregation models are similar to the part-of relationship in semantic data models.Object Models

Fig: Demonstration of object aggregation model

 


3 Interaction Model

  • The interaction model shows the interactions between objects to produce some particular system behavior that is specified as a use-case.
  • Sequence diagrams (or collaboration diagrams) in the UML are used to model interaction between objects.Object Models

Fig: Sequence diagram as interaction model


 

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A Soon-to-be Computer Engineer by profession, he has profound devotion to add Data Scientist as a prefix to his name. He’s been to the nooks of the web (at least of the surface web) and planning to add some real figures in his pocket!

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