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Object Reference Question

paul pavlentey

Joined: Jul 20, 2006
Posts: 10
I have very basic Java Question about object assignment.
public interface Animatable {
public void animate();
public class GameShape {
public void displayShape() {
System.out.println("Displaying Shape");

class which extends GameShape and implements interface Animatable
public class PlayerPiece extends GameShape implements Animatable{
public void movePiece() {
System.out.println("moving game piece");
public void animate() {


I dont understand the following assignement of variable "player".
I understand new object player is created (
PlayerPiece player= new PlayerPiece() ,
but how player is assigned to Object, GameShape and Animatable.
Object o=player;
GameShape shape=player;
Animatable mover=player;

What will it to player and how instances of Object, GameShape and Anumatable are effected?

Thanks in advance,
Barry Gaunt
Ranch Hand

Joined: Aug 03, 2002
Posts: 7729
Welcome to the Sun Certified Java Programmer Certification forum at JavaRanch.
I'm moving your question to our Java In General (Beginner) forum...

Ask a Meaningful Question and HowToAskQuestionsOnJavaRanch
Getting someone to think and try something out is much more useful than just telling them the answer.
It is sorta covered in the JavaRanch Style Guide.
subject: Object Reference Question
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