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Q) What is an interface?




A)
->An interface is a class like constructor of java language.
->”interface” keyword used to create an interface in java.
->An interface is compiled to “.class” file.
->An interface has variable & methods.
->A class can inherit from an interface.
->Reference variable (simply reference) can be created from an interface.
i.e. the interface reference is the user defined variable.
Ex:

interface I
{
      
}

class A {
       public static void main(String[] args) {
              I r;
       }

}

->An interface acts as a user defined data type. So an interface is not a primitive.

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