What is a supertype method?

java oop supertype
ray picture ray · Feb 28, 2013 · Viewed 23.3k times · Source

I have googled couple of times but still can't understand the supertype method. Can anyone please explain what is this?

Answer

navyad picture navyad · Feb 28, 2013

There is a notion of supertype and subtype in OOPS, In java this kind of relationship is implemented by inheritance i.e. using extends keyword:

class A {} // super class
class B extends A {} //sub class

Any member (fields, methods) declared in super class is to be called supertype.

Therefore in above context if class A has method like 

class A {
   void set()
}

Set is supertype method for class B.

However, notice that if there is another class say C: 

class C {
    void set()        
}

Then set() method is not supertype for C class because there is no relationship between class A and class C (relationship is created by extends keyword, for inheritance).

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