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Reformat rest of the design patterns - Issue #224

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This commit is contained in:
Ankur Kaushal
2015-11-01 21:29:13 -05:00
parent 449340bd2b
commit 306b1f3d31
337 changed files with 6744 additions and 6851 deletions
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68
double-dispatch/src/main/java/com/iluwatar/doubledispatch/App.java
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@@ -5,46 +5,50 @@ import java.util.List;
/**
*
* When a message with a parameter is sent to an object, the resultant behaviour is defined by the
* implementation of that method in the receiver. Sometimes the behaviour must also be determined
* by the type of the parameter.
* When a message with a parameter is sent to an object, the resultant behaviour is defined by the
* implementation of that method in the receiver. Sometimes the behaviour must also be determined by
* the type of the parameter.
* <p>
* One way to implement this would be to create multiple instanceof-checks for the methods parameter.
* However, this creates a maintenance issue. When new types are added we would also need to change
* the method's implementation and add a new instanceof-check. This violates the single responsibility
* principle - a class should have only one reason to change.
* One way to implement this would be to create multiple instanceof-checks for the methods
* parameter. However, this creates a maintenance issue. When new types are added we would also need
* to change the method's implementation and add a new instanceof-check. This violates the single
* responsibility principle - a class should have only one reason to change.
* <p>
* Instead of the instanceof-checks a better way is to make another virtual call on the parameter
* object. This way new functionality can be easily added without the need to modify existing
* implementation (open-closed principle).
* <p>
* In this example we have hierarchy of objects ({@link GameObject}) that can collide to each other. Each
* object has its own coordinates which are checked against the other objects' coordinates. If
* In this example we have hierarchy of objects ({@link GameObject}) that can collide to each other.
* Each object has its own coordinates which are checked against the other objects' coordinates. If
* there is an overlap, then the objects collide utilizing the Double Dispatch pattern.
*
*/
public class App {
/**
* Program entry point
* @param args command line args
*/
public static void main( String[] args ) {
// initialize game objects and print their status
List<GameObject> objects = new ArrayList<>();
objects.add(new FlamingAsteroid(0, 0, 5, 5));
objects.add(new SpaceStationMir(1, 1, 2, 2));
objects.add(new Meteoroid(10, 10, 15, 15));
objects.add(new SpaceStationIss(12, 12, 14, 14));
objects.stream().forEach(o -> System.out.println(o));
System.out.println("");
// collision check
objects.stream().forEach(o1 -> objects.stream().forEach(o2 -> { if (o1 != o2 && o1.intersectsWith(o2)) o1.collision(o2); } ));
System.out.println("");
// output eventual object statuses
objects.stream().forEach(o -> System.out.println(o));
System.out.println("");
}
/**
* Program entry point
*
* @param args command line args
*/
public static void main(String[] args) {
// initialize game objects and print their status
List<GameObject> objects = new ArrayList<>();
objects.add(new FlamingAsteroid(0, 0, 5, 5));
objects.add(new SpaceStationMir(1, 1, 2, 2));
objects.add(new Meteoroid(10, 10, 15, 15));
objects.add(new SpaceStationIss(12, 12, 14, 14));
objects.stream().forEach(o -> System.out.println(o));
System.out.println("");
// collision check
objects.stream().forEach(o1 -> objects.stream().forEach(o2 -> {
if (o1 != o2 && o1.intersectsWith(o2))
o1.collision(o2);
}));
System.out.println("");
// output eventual object statuses
objects.stream().forEach(o -> System.out.println(o));
System.out.println("");
}
}

16
double-dispatch/src/main/java/com/iluwatar/doubledispatch/FlamingAsteroid.java
View File

@@ -7,13 +7,13 @@ package com.iluwatar.doubledispatch;
*/
public class FlamingAsteroid extends Meteoroid {
public FlamingAsteroid(int left, int top, int right, int bottom) {
super(left, top, right, bottom);
setOnFire(true);
}
public FlamingAsteroid(int left, int top, int right, int bottom) {
super(left, top, right, bottom);
setOnFire(true);
}
@Override
public void collision(GameObject gameObject) {
gameObject.collisionResolve(this);
}
@Override
public void collision(GameObject gameObject) {
gameObject.collisionResolve(this);
}
}

75
double-dispatch/src/main/java/com/iluwatar/doubledispatch/GameObject.java
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@@ -2,48 +2,47 @@ package com.iluwatar.doubledispatch;
/**
*
* Game objects have coordinates and some
* other status information.
* Game objects have coordinates and some other status information.
*
*/
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 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;
}
public abstract void collision(GameObject gameObject);
public abstract void collisionResolve(FlamingAsteroid asteroid);
public abstract void collisionResolve(Meteoroid meteoroid);
private boolean damaged;
private boolean onFire;
public abstract void collisionResolve(SpaceStationMir mir);
public GameObject(int left, int top, int right, int bottom) {
super(left, top, right, bottom);
}
public abstract void collisionResolve(SpaceStationIss iss);
@Override
public String toString() {
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;
}
public abstract void collision(GameObject gameObject);
public abstract void collisionResolve(FlamingAsteroid asteroid);
public abstract void collisionResolve(Meteoroid meteoroid);
public abstract void collisionResolve(SpaceStationMir mir);
public abstract void collisionResolve(SpaceStationIss iss);
}

50
double-dispatch/src/main/java/com/iluwatar/doubledispatch/Meteoroid.java
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@@ -7,32 +7,36 @@ package com.iluwatar.doubledispatch;
*/
public class Meteoroid extends GameObject {
public Meteoroid(int left, int top, int right, int bottom) {
super(left, top, right, bottom);
}
public Meteoroid(int left, int top, int right, int bottom) {
super(left, top, right, bottom);
}
@Override
public void collision(GameObject gameObject) {
gameObject.collisionResolve(this);
}
@Override
public void collision(GameObject gameObject) {
gameObject.collisionResolve(this);
}
@Override
public void collisionResolve(FlamingAsteroid asteroid) {
System.out.println(String.format("%s hits %s.", asteroid.getClass().getSimpleName(), this.getClass().getSimpleName()));
}
@Override
public void collisionResolve(FlamingAsteroid asteroid) {
System.out.println(String.format("%s hits %s.", asteroid.getClass().getSimpleName(), this
.getClass().getSimpleName()));
}
@Override
public void collisionResolve(Meteoroid meteoroid) {
System.out.println(String.format("%s hits %s.", meteoroid.getClass().getSimpleName(), this.getClass().getSimpleName()));
}
@Override
public void collisionResolve(Meteoroid meteoroid) {
System.out.println(String.format("%s hits %s.", meteoroid.getClass().getSimpleName(), this
.getClass().getSimpleName()));
}
@Override
public void collisionResolve(SpaceStationMir mir) {
System.out.println(String.format("%s hits %s.", mir.getClass().getSimpleName(), this.getClass().getSimpleName()));
}
@Override
public void collisionResolve(SpaceStationMir mir) {
System.out.println(String.format("%s hits %s.", mir.getClass().getSimpleName(), this.getClass()
.getSimpleName()));
}
@Override
public void collisionResolve(SpaceStationIss iss) {
System.out.println(String.format("%s hits %s.", iss.getClass().getSimpleName(), this.getClass().getSimpleName()));
}
@Override
public void collisionResolve(SpaceStationIss iss) {
System.out.println(String.format("%s hits %s.", iss.getClass().getSimpleName(), this.getClass()
.getSimpleName()));
}
}

71
double-dispatch/src/main/java/com/iluwatar/doubledispatch/Rectangle.java
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@@ -2,43 +2,46 @@ package com.iluwatar.doubledispatch;
/**
*
* Rectangle has coordinates and can be checked for overlap against
* other Rectangles.
* Rectangle has coordinates and can be checked for overlap against other Rectangles.
*
*/
public class Rectangle {
private int left;
private int top;
private int right;
private int bottom;
private int left;
private int top;
private int right;
private int bottom;
public Rectangle(int left, int top, int right, int bottom) {
this.left = left;
this.top = top;
this.right = right;
this.bottom = bottom;
}
public int getLeft() {
return left;
}
public int getTop() {
return top;
}
public int getRight() {
return right;
}
public int getBottom() {
return bottom;
}
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());
}
public Rectangle(int left, int top, int right, int bottom) {
this.left = left;
this.top = top;
this.right = right;
this.bottom = bottom;
}
public int getLeft() {
return left;
}
public int getTop() {
return top;
}
public int getRight() {
return right;
}
public int getBottom() {
return bottom;
}
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());
}
}

14
double-dispatch/src/main/java/com/iluwatar/doubledispatch/SpaceStationIss.java
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@@ -7,12 +7,12 @@ package com.iluwatar.doubledispatch;
*/
public class SpaceStationIss extends SpaceStationMir {
public SpaceStationIss(int left, int top, int right, int bottom) {
super(left, top, right, bottom);
}
public SpaceStationIss(int left, int top, int right, int bottom) {
super(left, top, right, bottom);
}
@Override
public void collision(GameObject gameObject) {
gameObject.collisionResolve(this);
}
@Override
public void collision(GameObject gameObject) {
gameObject.collisionResolve(this);
}
}

69
double-dispatch/src/main/java/com/iluwatar/doubledispatch/SpaceStationMir.java
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@@ -7,45 +7,42 @@ package com.iluwatar.doubledispatch;
*/
public class SpaceStationMir extends GameObject {
public SpaceStationMir(int left, int top, int right, int bottom) {
super(left, top, right, bottom);
}
public SpaceStationMir(int left, int top, int right, int bottom) {
super(left, top, right, bottom);
}
@Override
public void collision(GameObject gameObject) {
gameObject.collisionResolve(this);
}
@Override
public void collision(GameObject gameObject) {
gameObject.collisionResolve(this);
}
@Override
public void collisionResolve(FlamingAsteroid asteroid) {
System.out.println(String.format("%s hits %s. %s is damaged! %s is set on fire!",
asteroid.getClass().getSimpleName(), this.getClass().getSimpleName(),
this.getClass().getSimpleName(), this.getClass().getSimpleName()));
setDamaged(true);
setOnFire(true);
}
@Override
public void collisionResolve(FlamingAsteroid asteroid) {
System.out.println(String.format("%s hits %s. %s is damaged! %s is set on fire!", asteroid
.getClass().getSimpleName(), this.getClass().getSimpleName(), this.getClass()
.getSimpleName(), this.getClass().getSimpleName()));
setDamaged(true);
setOnFire(true);
}
@Override
public void collisionResolve(Meteoroid meteoroid) {
System.out.println(String.format("%s hits %s. %s is damaged!",
meteoroid.getClass().getSimpleName(), this.getClass().getSimpleName(),
this.getClass().getSimpleName()));
setDamaged(true);
}
@Override
public void collisionResolve(Meteoroid meteoroid) {
System.out.println(String.format("%s hits %s. %s is damaged!", meteoroid.getClass()
.getSimpleName(), this.getClass().getSimpleName(), this.getClass().getSimpleName()));
setDamaged(true);
}
@Override
public void collisionResolve(SpaceStationMir mir) {
System.out.println(String.format("%s hits %s. %s is damaged!",
mir.getClass().getSimpleName(), this.getClass().getSimpleName(),
this.getClass().getSimpleName()));
setDamaged(true);
}
@Override
public void collisionResolve(SpaceStationMir mir) {
System.out.println(String.format("%s hits %s. %s is damaged!", mir.getClass().getSimpleName(),
this.getClass().getSimpleName(), this.getClass().getSimpleName()));
setDamaged(true);
}
@Override
public void collisionResolve(SpaceStationIss iss) {
System.out.println(String.format("%s hits %s. %s is damaged!",
iss.getClass().getSimpleName(), this.getClass().getSimpleName(),
this.getClass().getSimpleName()));
setDamaged(true);
}
@Override
public void collisionResolve(SpaceStationIss iss) {
System.out.println(String.format("%s hits %s. %s is damaged!", iss.getClass().getSimpleName(),
this.getClass().getSimpleName(), this.getClass().getSimpleName()));
setDamaged(true);
}
}

12
double-dispatch/src/test/java/com/iluwatar/doubledispatch/AppTest.java
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@@ -10,10 +10,10 @@ import com.iluwatar.doubledispatch.App;
*
*/
public class AppTest {
@Test
public void test() {
String[] args = {};
App.main(args);
}
@Test
public void test() {
String[] args = {};
App.main(args);
}
}

14
double-dispatch/src/test/java/com/iluwatar/doubledispatch/RectangleTest.java
View File

@@ -12,11 +12,11 @@ import com.iluwatar.doubledispatch.Rectangle;
*/
public class RectangleTest {
@Test
public void test() {
Assert.assertTrue(new Rectangle(0,0,1,1).intersectsWith(new Rectangle(0,0,1,1)));
Assert.assertTrue(new Rectangle(0,0,1,1).intersectsWith(new Rectangle(-1,-5,7,8)));
Assert.assertFalse(new Rectangle(0,0,1,1).intersectsWith(new Rectangle(2,2,3,3)));
Assert.assertFalse(new Rectangle(0,0,1,1).intersectsWith(new Rectangle(-2,-2,-1,-1)));
}
@Test
public void test() {
Assert.assertTrue(new Rectangle(0, 0, 1, 1).intersectsWith(new Rectangle(0, 0, 1, 1)));
Assert.assertTrue(new Rectangle(0, 0, 1, 1).intersectsWith(new Rectangle(-1, -5, 7, 8)));
Assert.assertFalse(new Rectangle(0, 0, 1, 1).intersectsWith(new Rectangle(2, 2, 3, 3)));
Assert.assertFalse(new Rectangle(0, 0, 1, 1).intersectsWith(new Rectangle(-2, -2, -1, -1)));
}
}