Determine output:
class A{
public void method1(){
System.out.print("Class A method1");
}
}
class B extends A{
public void method2(){
System.out.print("Class B method2");
}
}
class C extends B{
public void method2(){
System.out.print("Class C method2");
}
public void method3(){
System.out.print("Class C method3");
}
}
public class Test{
public static void main(String args[]){
A a = new A();
C c = new C();
c.method2();
a = c;
a.method3();
}
}
class A{
public void method1(){
System.out.print("Class A method1");
}
}
class B extends A{
public void method2(){
System.out.print("Class B method2");
}
}
class C extends B{
public void method2(){
System.out.print("Class C method2");
}
public void method3(){
System.out.print("Class C method3");
}
}
public class Test{
public static void main(String args[]){
A a = new A();
C c = new C();
c.method2();
a = c;
a.method3();
}
}A. Class B method2 Class C method3
B. Class C method2 Class C method3
C. Compilation Error
D. Runtime exception
E. None of these
Answer: Option C
Solution (By Examveda Team)
It is important to understand that it is the type of reference variable - not the type of the object that it refers to - that which determines what members can be accessed. That is, when a reference to a subclass object is assigned to a super class reference variable, we will have access only to those parts of the object defined by the superclass.
In the above program method method3() is defined in the class C which is a subclass of B and so A. Even the reference variable a refers to c, a can't access method3() as this method is unknown to class A.
This Question Belongs to Java Program >> Inheritence
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