What role does abstraction play in object oriented programming?

Answer 1

Answer for abstractionAbstraction is a oops concept. It provides a facility to hide some unimportant information and provide us some information which is important for the client programmers.

Eg If we consider a car which has lot of parts such as wheels steering DVD player etc.

We need to know how to use it. We need not know what is the

structure of all these parts to buy and drive a car.

Another eg is Television. The Television has lot of properties and behavoiurs like height width displayOn,displayOff etc and also it has chips and internal wires which enables the television's functions.

But for working the Television we don't need to know these internal things.

Answer 2

The interface creates a contract between the client and the implementer. The client knows the interface but should not have to know how the implementer provided that interface. This has several benefits. First, the interface protects the implementer from incorrect use of the data structure by the client. An interface creates an abstraction barrier that protects the implementation. A client that uses knowledge of the implementation not contained in the interface is violating the abstraction barrier. The interface to a data abstraction is also said to encapsulate the implementation details. Second, the interface also gives the implementer flexibility to change the implementation, as long as the client is only using the implementation through the defined operations, and those operations are still provided by the new implementation. This flexibility results in a loosely coupled system. The interface creates a contract between the client and implementer, which frees them up to work more independently as long as they stick to the contract. In a tightly coupled system, the client and the implementation are not as free to change because changes to either are more likely to change the interface. Third, when something goes wrong in a program, the presence of an interface makes it easier to assign blame to either the client or the implementer. Either the client is using the interface incorrectly (possibly violating the abstraction barrier), or the implementer is implementing it incorrectly. A clear interface makes it possible to argue that one of the two needs to fix their code.

Answer 3

Abstraction makes it possible for class designers to alter the implementation or the underlying representation of a class without affecting the consumers of that class. That is, the scope of change can be limited to the class itself. From the user's point of view, so long as the interface remains the same, nothing has actually changed, thus all existing code remains unaffected.

Answer 4

Abstraction is simplifying complex reality by modelling classes appropriate to the problem, and working at the most appropriate level of inheritance for a given aspect of the problem.

For example, Lassie the Dog may be treated as a Dog much of the time, a Collie when necessary to access Collie-specific attributes or behaviors, and as an Animal (perhaps the parent class of Dog) when counting Timmy's pets.

Abstraction is also achieved through Composition. For example, a class Car would be made up of an Engine, Gearbox, Steering objects, and many more components. To build the Car class, one does not need to know how the different components work internally, but only how to interface with them, i.e., send messages to them, receive messages from them, and perhaps make the different objects composing the class interact with each other.

Answer 5

- Abstraction in OOP is intended to facilitate re usability of the code
- To facilitate polymorphism
- Abstraction lets you focus on what the object does instead of how it does it.
- Abstraction helps in defining a contract between the consumer and provider. The consumer wont get affected even if the internal implementation of the provider will change. Which confirms to the OOP principle "A class should be open for extension but close for the modification"

Answer 6

1.Abstraction in Java allows the user to hide non-essential details relevant to user.

2.Java has concept of abstract classes , abstract method but a variable can not be abstract