Page 16 - DCAP404 _Object Oriented Programming
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Unit 1: Review of Object-oriented Programming




                                                                                                Notes
                   Figure  1.6:  Relationship  of  Data  and Functions  in Procedural  Programming



                                           Global data items
                Function-1                                               Function-3







                         Function-2                              Function-4




                                              Function-5



             Did u know?  What is the basic feature of Procedural-oriented Programming?
          The basic feature of Procedural-oriented Programming is to reuse the same code at different
          places in the program without coping it.
          Another serious drawback with the procedural approach is that it does not model real world
          problems very well. This is because functions are action-oriented and do not really correspond
          to the elements of the problem.
          Some characteristics exhibited by procedure-oriented programming are:

          1.   Emphasis is on doing things (algorithms).
          2.   Large programs are divided into smaller programs known as functions.
          3.   Most of the functions share global data.
          4.   Data move openly around the system from function to function.

          1.3.2  Object-oriented Programming Paradigm

          The term Object-oriented Programming (OOP) is widely used, but experts do not seem to agree
          on its exact definition. However, most experts agree that OOP involves defining Abstract Data
          Types (ADT) representing complex real-world or abstract objects  and organizing programs
          around the collection of ADTs with an eye toward exploiting their common features. The term
          data abstraction refers to the process of defining ADTs; inheritance and polymorphism refer to
          the mechanisms that enable you to take advantage of the common characteristics of the ADTs –
          the objects in OOP.

          Before going any further into OOP, take note of two points. First, OOP  is only a method of
          designing and implementing software. Use of object-oriented techniques  does  not  impart
          anything to a finished software product that the user can see. However, as a programmer while
          implementing  the software, you  can gain significant advantages  by using  object-oriented
          methods, especially in large software projects. Because OOP enables you to remain close to the
          conceptual, higher-level model of the real world problem  you are  trying to  solve, you  can
          manage the complexity better than with approaches that force you to map the problem to fit the
          features of the language. You can take advantage of the modularity of objects and implement the




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