Added iteration logic.

double-dispatch/src/main/java/com/iluwatar/App.java

@@ -1,7 +1,16 @@
 package com.iluwatar;
 
+import java.util.ArrayList;
+import java.util.List;
+
 public class App {
 	
     public static void main( String[] args ) {
+    	List<GameObject> objects = new ArrayList<>();
+    	objects.add(new FlamingAsteroid(0, 0, 5, 5));
+    	objects.add(new SpaceStationMir(1, 1, 4, 4));
+    	objects.add(new Meteoroid(10, 10, 15, 15));
+    	objects.add(new SpaceStationIss(12, 11, 14, 15));
+    	objects.stream().forEach(o1 -> objects.stream().forEach(o2 -> { if (o1 != o2) System.out.println(String.format("%s -> %s", o1, o2)); } ));
     }
 }

double-dispatch/src/main/java/com/iluwatar/Asteroid.java

@@ -1,8 +0,0 @@
-package com.iluwatar;
-
-public class Asteroid extends Meteoroid {
-
-	public Asteroid(int left, int top, int right, int bottom) {
-		super(left, top, right, bottom);
-	}
-}

double-dispatch/src/main/java/com/iluwatar/FlamingAsteroid.java

@@ -0,0 +1,9 @@
+package com.iluwatar;
+
+public class FlamingAsteroid extends Meteoroid {
+
+	public FlamingAsteroid(int left, int top, int right, int bottom) {
+		super(left, top, right, bottom);
+		setOnFire(true);
+	}
+}

double-dispatch/src/main/java/com/iluwatar/GameObject.java

@@ -2,12 +2,32 @@ package com.iluwatar;
 
 public abstract class GameObject extends Rectangle {
 	
+	private boolean damaged;
+	private boolean onFire;
+	
 	public GameObject(int left, int top, int right, int bottom) {
 		super(left, top, right, bottom);
 	}
 	
 	@Override
 	public String toString() {
-		return this.getClass().getSimpleName();
+		return String.format("%s at %s damaged=%b onFire=%b", this.getClass().getSimpleName(), 
+				super.toString(), isDamaged(), isOnFire());
+	}
+	
+	public boolean isOnFire() {
+		return onFire;
+	}
+	
+	public void setOnFire(boolean onFire) {
+		this.onFire = onFire;
+	}
+	
+	public boolean isDamaged() {
+		return damaged;
+	}
+	
+	public void setDamaged(boolean damaged) {
+		this.damaged = damaged;
 	}
 }

double-dispatch/src/main/java/com/iluwatar/Rectangle.java

@@ -30,4 +30,9 @@ public class Rectangle {
 	boolean intersectsWith(Rectangle r) {
 		return !(r.getLeft() > getRight() || r.getRight() < getLeft() || r.getTop() > getBottom() || r.getBottom() < getTop());
 	}
+	
+	@Override
+	public String toString() {
+		return String.format("[%d,%d,%d,%d]", getLeft(), getTop(), getRight(), getBottom());
+	}
 }