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Q) What are the difference between static variables and instance variables?




A)
No
                      Static variables
No
                   Instance variables
1
Per class only one copy irrespective of number of  objects
1
Per object one separate copy
2
It is used to represent entire class information but not individual object information
2
Meant for representing individual object information
3
Doesn’t contribute to the size of object
3
Contribute to the size of the object
4
Shared by each object and manipulated by the behaviour of the object
4
Owned by one object
5
Comes into existence as soon as the class is loaded and before any object is created
5
Comes into existence only when object is created
6
memory is deallocated when class is unloaded
6
memory is deallodated only when the object is garbage collected
7
Both static and instance method can access them
7
Only instance methods can access them  and static methods can’t refer them
8
Can refer both of them with class name and object name
8
Can’t refer them with class

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