Object-oriented design

Posted By on April 29, 2016


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Design Verification
Object-oriented concepts
  • Object-oriented design is the process of planning a system of interacting objects for the purpose of solving a software problem.
  • An object contains encapsulated data and procedures grouped together to represent an entity.
  • The ‘object interface’ defines how the object can be interacted with.
  • An object-oriented program is described by the interaction of these objects.
  • Object-oriented design is the discipline of defining the objects and their interactions to solve a problem that was identified and documented during object-oriented analysis.
  • What follows is a description of the class-based subset of object-oriented design, which does not include object prototype-based approaches where objects are not typically obtained by instancing classes but by cloning other (prototype) objects.
  • Object-oriented design is a method of design encompassing the process of object-oriented decomposition and a notation for depicting both logical and physical as well as state and dynamic models of the system under design.
  • The input for object-oriented design is provided by the output of object-oriented analysis.
  • Realize that an output artifact does not need to be completely developed to serve as input of object-oriented design; analysis and design may occur in parallel, and in practice the results of one activity can feed the other in a short feedback cycle through an iterative process.
  • Both analysis and design can be performed incrementally, and the artifacts can be continuously grown instead of completely developed in one shot.Some typical input artifacts for object-oriented design are:
    • Conceptual model: The result of object-oriented analysis, it captures concepts in the problem domain. The conceptual model is explicitly chosen to be independent of implementation details, such as concurrency or data storage.
    • Use case: A description of sequences of events that, taken together, lead to a system doing something useful. Each use case provides one or more scenarios that convey how the system should interact with the users called actors to achieve a specific business goal or function. Use case actors may be end users or other systems. In many circumstances use cases are further elaborated into use case diagrams. Use case diagrams are used to identify the actor (users or other systems) and the processes they perform.
    • System sequence diagram: A system sequence diagram (SSD) is a picture that shows, for a particular scenario of a use case, the events that external actors generate, their order, and possible inter-system events.
    • User interface documentations (if applicable): Document that shows and describes the look and feel of the end product’s user interface. It is not mandatory to have this, but it helps to visualize the end-product and therefore helps the designer.
    • Relational data model (if applicable): A data model is an abstract model that describes how data is represented and used. If an object database is not used, the relational data model should usually be created before the design, since the strategy chosen for object-relational mapping is an output of the OO design process. However, it is possible to develop the relational data model and the object-oriented design artifacts in parallel, and the growth of an artifact can stimulate the refinement of other artifacts.
Design Verification
Object-oriented concepts

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Posted by Akash Kurup

Founder and C.E.O, World4Engineers Educationist and Entrepreneur by passion. Orator and blogger by hobby

Website: http://world4engineers.com