Program to explain Inheritance of a interface in Java

//  Program to explain Inheritance of a interface
//  from another interface.
interface AInterface
{
void showA();
}
interface BInterface extends AInterface 
{
void showB();
}
class Test  implements BInterface
{
public void showA()
{
 System.out.println("showA() of A interface.");
}

public void showB()
{
 System.out.println("showB() of B interface.");
}
}
class InterfaceTest4
{
public static void main( String args[ ] )
{
 AInterface  a1 = new Test();
 a1.showA();
 
 BInterface b1 = new Test();
 b1.showA();
 b1.showB();
}
}

Output:
showA() of A interface.
showA() of A interface.
showB() of B interface.