A Java program using abstarct keyword

A Simple demonstration of ........ abstract keyword ..........

abstract class A

 { 
abstract void callme(); 
// concrete methods are still allowed in abstract classes 
void callmetoo()

 { 
System.out.println("This is a concrete method."); 
} 
}

class B extends A

 { 
void callme()

 { 
System.out.println("B's implementation of callme."); 
} 
}

class AbstractDemo

 { 
public static void main(String args[])

 { 
B b = new B(); 
b.callme(); 
b.callmetoo(); 
} 
}

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