Instanceof operator in Java

Example



class A
{
int i,j;
}
class B
{
int i,j;
}
class C extends A
{
int k;
}
class D extends A
{
int k;
}
class A404306
{
public static void main(String args[])
{
A a=new A();
B b=new B();
C c=new C();
D d=new D();
if (a instanceof A)
System.out.println(" a is instance of A");
if (b instanceof B)
System.out.println(" b is instance of B");
if (c instanceof C)
System.out.println(" c is instance of C");
if (c instanceof A)
System.out.println(" c can be cast of A");
if (a instanceof C)
System.out.println(" a can be case of C");
System.out.println();
A ob;
ob=d;
System.out.println("ob now refers to d");
if(ob instanceof D)
System.out.println("ob is instance of D");
ob=c;
System.out.println("ob now refers to c");
if(ob instanceof D)
System.out.println("ob can be cast to D");
else
System.out.println("ob cannot be cast to D");

if(ob instanceof A)
System.out.println("ob can be cast to A");
System.out.println();

if(a instanceof Object)
System.out.println("a may be cast to Object");
if(b instanceof Object)
System.out.println("b may be cast to Object");
if(c instanceof Object)
System.out.println("c may be cast to Object");
if(d instanceof Object)
System.out.println("d may be cast to Object");
}
}