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About Software Design and Development

When we plan to design a software we need to focus certain things. Here are some important points we can go through.

Functional Decomposition:

  • Functional decomposition is natural way to deal with complexity.

  • The challenges with this approach: to dealing with change and bugs originate with changes to code.

  • Low cohesion, tight coupling

  • Focus on function leads to a cascade of changes from which it is difficult to escape.

The Problem of Requirements:

  • Requirements always change.

  • Requirements are incomplete.

  • Requirements are usually wrong.

  • Requirements (and users) are misleading.

  • Requirements do not tell the whole story.

Deal with Changes(Use Functional Decomposition):

  • Shift responsbility from yourself to individuals.

Perspectives:

  • Conceptual - Only think about problem domain forget about Softwares.

  • Specification - Only think of Software interfaces No Codes.

  • Implementation - Code it.

Object Oriented Paradigm:

  • You may think of objects by looking nouns and verbes in the requirements documnet.

  • Abstract classes give us a way to assign a name to a set of related classes.


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