Object oriented approach is based upon the data abstraction. In object oriented design methodology, the decomposition of a system based upon objects. In functional methods, each module represent a function or operation to perform an activity in the system.
In object oriented design methodology (OODM), module is a object, which is not a functional entity that represent an operation but an entity that represent some data items in system together with operation can be performed on data item.
What Is Object Oriented Design Methodology? Explain its approaches
- Producing the initial design
- Functional refinement
- Object refinement
Producing the initial design:-
One way to define the object and operation on object is to start with a strategy.
There are 3 basic steps:-
- Develop a strategy
- Identify the objects and operation on objects
- Establish the interface of objects
We will specify a strategy to solve problem. We use the English to define strategy. Strategy would contain the operation to be performed and decision to be take in order to solve the problem.
For example:-
A strategy may contain a repeatedly read an element from input file and add it to list until the list is full. A strategy contain user defined operation. The operation don’t perform in a vacuum.
To identify operation, we realize that an operation will always be performed, we have to identify the phase represent the actions. The phase that represent some action often represent actions and phase that represent some entities in system usually represent the object. Here the function are refined during the functional refinement.
Once the object, operation on object and function to be further refined are defined, the strategy can be formalized by defining a function which implements the strategy. A strategy is a normal strategy to solve the problem.
Functional refinement
What Is Object Oriented Design Methodology? Explain its approaches.
During refinement step, operation may also be identified on objects that were identified in earlier refinement steps. When the refinement process terminates, the transformation function solve the problem.
In addition, when function refinement terminates all the objects in problem space are identified. The object that have been identified are commonly objects need to specify system components.
A natural strategy to implement function is to initialize the count to 0. Se previous word to NIL. Get a word from word list if same is previous word. No change count report until the list is empty. In it we find the two operations namely get a word and is list empty.
Object refinement:-
In this phase, we turn our attention to objects. The aim of this phase to identify objects and operations that are required in order to implement the objects. To refine the objects, we identify the new object and their operation that are required in order to implement these operations. This process is repeated for each object and we refer to this process as object refinement.