gistfile1.java

interface Z { }
class Y extends X { public String toString() { return "Y"; } }
class X implements Z { public String toString() { return "X"; } }
public class Test {
    public static void main(String[] args) {
    	Y y = new Y();
    	X x = y;
    	Z z = x;
    	System.out.print(x + " ");
    	System.out.print((Y)x + " ");
    	System.out.print(z + " ");
    }
}