what is run time polymorphism
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Answer / vijayakumar chinnasamy
In Java Method overriding is the runtime or late binding
polymorphism.
class object is determine which class method is invoked.
ex:
class A {
protected void display(){ }
}
class B extends A {
protected void display(){ }
}
class MainClass {
public static void main(String arg[]){
A objA=null;
objA=new B();
objA.display(); // it invoke the Class B's display()
objA=new A();
objA.display(); // it invoke the Class A's display()
}
}
Note: the class's object only determine which method to call.
| Is This Answer Correct ? | 2 Yes | 0 No |
Answer / durgasri
In runtime polymorphism ... the code is called at run time
according to need or given conditions.
suppose there r two methods namely Add() one in super class
and other is in sub class.both have the same name and same
parameters.
so we have to choose that which method from them shld
called at run time i.e. of super class or of sub class.by
polymorphism we do that.
ex:-
class A
{
int add(){//code of the method}
//some other code
}
class B extends A
{
int add(){//code of the method}
//some other code
}
class AB
{
public static void main(String s[])
{
A ob1;
ob1=new A();
int i=ob1.add();//will call the method of super class.
ob1=new B();// sub class's reference can be assigned to
super class address but not vice versa.to do that we have
to type cast the reference of the sub class in reference of
the super class.
int j=ob1.add();//will call the method of sub class
}
}
| Is This Answer Correct ? | 1 Yes | 0 No |
Answer / shiry
In C++ ;
if i have 2 clases
class A {
int x();
}
class B : public A {
int x();
}
void main(){
A* a = new B() ;
a.x(); // it will call the method of the super class A
// not B but in java it will call the method in the
// child B why ??
}
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / venu
Runtime polymorphism is nothing but, JVM identifies the behavior (Method) invocation of the reference based on the reference pointing to the Object. Runtime Polymorphism is experimented by an example of Method Overriding.
| Is This Answer Correct ? | 0 Yes | 0 No |
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