More examples of such code..

[jose chiramal]

I want to understand the two blocks used in the below code. Also where can i find more examples of such code :

interface  I1
{
void meth();
}

interface  I2
{
void show();

}
interface  I3 extends  I1,I2
{
	void  meth1();
}
abstract class  InterfaceImpl implements  I3  
{
	public  void  meth1()
	{
		System.out.println ( "In meth1() of Class InterfaceImpl" );
	}
	public  void  meth()
	{
		System.out.println ( "In meth() of Class InterfaceImpl" );
	}

}
class  SubInterfaceImpl extends  InterfaceImpl
{
	public  void  show()
	{
		System.out.println ( "In show of Class SubInterfaceImpl" );
	}
}
class  InterfaceDemo
{
	public static void main(String[] args) 
	{
		I1 i1 = new SubInterfaceImpl();
		if (i1 instanceof I3)
		{
            System.out.println("hello..entered the if block");
			I3 i3 = (I3)i1;
			i3.meth1();
		}
		
		 I3 i3 = new SubInterfaceImpl();
if (i3 instanceof I1)
 {
            System.out.println("hello..entered the 2nd if block");	
 }
    }
}

[jose chiramal]

Sorry for posting multiple times.. Was trying to get the format correct. I would like to understand the if block used here. Whats this concept called as ?

Thanks

[Jesper de Jong]

It's just a normal if-statement. Do you mean that you want to learn what the instanceof operator does?

You can find that here in Sun's Java Tutorials: The Type Comparison Operator instanceof (scroll down on that page).

[jose chiramal]

Yes I would like to know how the instanceof operator can be used with interface references and with objects.

Thanks.

[Ulf Dittmer]

Just for future reference: you don't need to post again, you can use the button to edit a post.