JAVA接口示例

interface drawTest{

 public void draw();

 public void doAnyThing();

class ParallelogramUserInterface extends QuadrangleUserInterface implements drawTest{

 public void draw(){

 System.out.println("Parallelogram.draw()");

 public void doAnyThing(){

 System.out.println("This is ParallelogramUserInterface doAnyThing method.");

class SquareUserInterface extends QuadrangleUserInterface implements drawTest{

 public void draw(){

 System.out.println("SquareUserInterface.draw()");

 public void doAnyThing(){

 System.out.println("This is SquareUserInterface doAnyThing method.");

class AnyThingUserInterface extends QuadrangleUserInterface{

 public void doAnyThing(){

 System.out.println("This is AnyThingUserInterface doAnyThing method.");

public class QuadrangleUserInterface implements drawTest{

 public void doAnyThing(){

 System.out.println("This is QuadrangleUserInterface doAnyThing method.");

 public void draw(){

 System.out.println("QuadrangleUserInterface.draw()");

 public static void main(String[] args) {

 // TODO Auto-generated method stub

 drawTest[] d={new SquareUserInterface(),

 new ParallelogramUserInterface(),

 new QuadrangleUserInterface()};

 for(int i = 0; i d.length; i++){

 System.out.println(i);

 d[i].draw();

 d[i].doAnyThing();

}

输出：

0
SquareUserInterface.draw()
This is SquareUserInterface doAnyThing method.
1
Parallelogram.draw()
This is ParallelogramUserInterface doAnyThing method.
2
QuadrangleUserInterface.draw()
This is QuadrangleUserInterface doAnyThing method.