CONCEPTS OF OBJECTS:

OBJECTS:

AN OBJECT CAN BE THOUGHT AS AN ENTITY HAVING SPECIFIC IDENTITY , CHARACTERISTICS AND BEHAVIOUR.

 

STATE OF OBJECTS:

THE STATE OF OBJECT IS REPRESENTED THROUGH ITS VALUES OR ATTRIBUTES OF ITS CHARACTERISTICS AT A GIVEN POINT OF TIME.

 

ABSTRACTION:

ABSTRACTION REFERS TO THE ACT OF REPRESENTING ESSENTIAL FEATURES WITHOUT INCLUDING BACKGROUND DETAILS AND EXPLANATION. IT IS ALWAYS RELATIVE TO CONTENT.

 

ENCAPSULATION:

THE WRAPPING UP OF DATA AND FUNCTIONS INTO SINGLE UNIT(OBJECT) IS CALLED ENSCAPSULATION. IT IS THE WAY TO IMPLEMENT DATA ABSTRACTION. IT HIDES THE DETAILS OF THE IMPLEMENTATION OF OBJECTS.

 

 

SINCE STATE AND BEHAVIOUR OF OBJECT ARE INTERWOVEN, THEY ARE SAID TO ENCAPSULATE STATE AND BEHAVIOUR.WE CANNOT SEGRGATE THEM. THUS, WE CAN SAY OBJECTS ENCAPSULATE STATE AND BEHAVIOUR, AS THEIR STATE  AND BEHAVIOUR ARE INTERLINKED. THUS THEY CANNOT EXIST SEPARATELY.

 

STATE IS MAINTAINED THROUGH VARIABLES OR DATA ITEMS (MEMBER VARIABLES THAT HOLD DATA).BEHAVIOUR IS MAINTAINED THROUGH FUNCTIONS OR METHODS

 

WHEN OBJECTS NEED TO INTERACT WITH ONE ANOTHER, THEY INTERACT BY PASSING MESSAGES TO ONE ANOTHER. THIS IS KNOWN AS MESSAGE PASSING.

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