Comment Entity, make x and y private, add transpose method for easy movement.

src/de/teamteamteam/spacescooter/entity/Entity.java

@@ -8,68 +8,126 @@ import de.teamteamteam.spacescooter.screen.Screen;
 import de.teamteamteam.spacescooter.utility.GameConfig;
 import de.teamteamteam.spacescooter.utility.Loader;
 
+/**
+ * The basic Entity class where all the logic of objects begins.
+ * Every Entity is Updateable and Paintable.
+ * It knows about its X/Y Position and its default image.
+ * Also, it is able to paint itself in the default way.
+ */
 public abstract class Entity implements Updateable, Paintable {
 	
 	/**
-	 * Entity position
+	 * Entity position.
+	 */
+	private int x;
+	private int y;
+	
+	/**
+	 * Entity width and height.
+	 */
+	private int width;
+	private int height;
+	
+	/**
+	 * Internal reference to the entities image.
 	 */
-	protected int x;
-	protected int y;
 	private BufferedImage img;
 	
+	
 	/**
 	 * Constructor.
 	 * All entities are within a static array list for our convenience.
 	 */
 	public Entity(int x, int y) {
-		this.x = x;
-		this.y = y;
+		this.setPosition(x, y);
 		Screen.currentScreen.addEntity(this);
 	}
 	
+	
+	/**
+	 * Get the X-Position of the Entity.
+	 */
 	public int getX() {
 		return this.x;
 	}
 
+	/**
+	 * Get the Y-Position of the Entity.
+	 */
 	public int getY() {
 		return this.y;
 	}
 	
-	public int getWidth() {
-		if(this.img == null) return 0; //no image -> nothing visible -> no width
-		return this.img.getWidth();
-	}
-
-	public int getHeight() {
-		if(this.img == null) return 0; //no image -> nothing visible -> no height
-		return this.img.getHeight();
-	}
-	
+	/**
+	 * Set the Entities new absolute position.
+	 */
 	public void setPosition(int x, int y) {
 		this.x = x;
 		this.y = y;
 	}
+
+	/**
+	 * Moves the entity by the given X/Y deltas.
+	 * Example: X = X + x_delta, Y = Y + y_delta.
+	 */
+	public void transpose(int x_delta, int y_delta) {
+		this.x += x_delta;
+		this.y += y_delta;
+	}
 	
+	/**
+	 * Get the Entities width.
+	 */
+	public int getWidth() {
+		return this.width;
+	}
+	
+	/**
+	 * Get the Entities height.
+	 */
+	public int getHeight() {
+		return this.height;
+	}
+
+	/**
+	 * Set the entities width and height.
+	 */
+	public void setDimensions(int width, int height) {
+		this.width = width;
+		this.height = height;
+	}
+	
+	/**
+	 * Gets the Entities BufferedImage.
+	 */
 	public BufferedImage getImage() {
 		return this.img;
 	}
 
+	/**
+	 * Sets the Entities BufferedImage by fetching it through the Loader.
+	 */
 	public void setImage(String filename) {
 		this.img = Loader.getBufferedImageByFilename(filename);
+		//set the entities dimensions using the dimensions of the image.
+		this.setDimensions(this.img.getWidth(), this.img.getHeight());
 	}
 	
+	/**
+	 * The default way to paint the Entity.
+	 * Simply draw the Entities image on its current position.
+	 */
 	public void paint(Graphics2D g) {
-		//DEBUG ONLY
 		if(GameConfig.DEBUG) {
 			g.setColor(new Color(255,0,0));
-			g.drawRect(this.x, this.y, this.getWidth(), this.getHeight());
+			g.drawRect(this.x, this.y, this.width, this.height);
 		}
-		
 		g.drawImage(this.img, this.x, this.y, null);
 	}
 	
 	/**
-	 * Removes entity from the game
+	 * Removes entity from the game by telling the current Screen
+	 * to remove it from its list.
 	 */
 	public void remove() {
 		Screen.currentScreen.removeEntity(this);

src/de/teamteamteam/spacescooter/entity/HealthBar.java

@@ -27,7 +27,7 @@ public class HealthBar extends Entity {
 		Graphics2D grpahic = (Graphics2D) g;
 		this.g = grpahic;
 		this.g.setColor(new Color(0,255,0));
-		this.g.fillRect(this.x, this.y, this.width, this.height);
+		this.g.fillRect(this.getX(), this.getY(), this.width, this.height);
 	}
 	
 	public void update() {

src/de/teamteamteam/spacescooter/entity/LivingEntity.java

@@ -94,7 +94,7 @@ public abstract class LivingEntity extends Entity implements Collidable {
 	}
 
 	public void explode() {
-		new Explosion(this.x, this.y);
+		new Explosion(this.getX(), this.getY());
 	}
 
 	public void setHealthPoints(int hp) {

src/de/teamteamteam/spacescooter/entity/Player.java

@@ -34,18 +34,18 @@ public class Player extends ShootingEntity implements KeyboardListener {
 	public void update() {
 		if(this.canMove) {
 			super.update();
-			int off = 3;
-			if(Keyboard.isKeyDown(KeyEvent.VK_UP) && this.y > 0) {
-				this.y -= off;
+			int offset = 3;
+			if(Keyboard.isKeyDown(KeyEvent.VK_UP) && this.getY() > 0) {
+				this.transpose(0, -1 * offset);
 			}
-			if(Keyboard.isKeyDown(KeyEvent.VK_DOWN) && this.y < (GameConfig.windowHeight - this.getImage().getHeight())) {
-				this.y += off;
+			if(Keyboard.isKeyDown(KeyEvent.VK_DOWN) && this.getY() < (GameConfig.windowHeight - this.getImage().getHeight())) {
+				this.transpose(0, offset);
 			}
-			if(Keyboard.isKeyDown(KeyEvent.VK_LEFT) && this.x > 0) {
-				this.x -= off;
+			if(Keyboard.isKeyDown(KeyEvent.VK_LEFT) && this.getX() > 0) {
+				this.transpose(-1 * offset, 0);
 			}
-			if(Keyboard.isKeyDown(KeyEvent.VK_RIGHT) && this.x < (GameConfig.windowWidth - this.getImage().getWidth())) {
-				this.x += off;
+			if(Keyboard.isKeyDown(KeyEvent.VK_RIGHT) && this.getX() < (GameConfig.windowWidth - this.getImage().getWidth())) {
+				this.transpose(offset, 0);
 			}
 			//continuous fire takes place here
 			if(Keyboard.isKeyDown(KeyEvent.VK_SPACE)) {

src/de/teamteamteam/spacescooter/entity/ShootingEntity.java

@@ -36,8 +36,8 @@ public abstract class ShootingEntity extends LivingEntity {
 
 	public void createShot() {
 		new Shot(
-				this.x + this.shootSpawnX,
-				this.y + this.shootSpawnY,
+				this.getX() + this.shootSpawnX,
+				this.getY() + this.shootSpawnY,
 				this.shootDirection,
 				this.shootSpeed,
 				this.damageValue,

src/de/teamteamteam/spacescooter/entity/enemy/EnemyThree.java

@@ -48,10 +48,10 @@ public class EnemyThree extends Enemy{
 			Entity entity = i.next();
 			if(entity instanceof Player){
 				Player player = (Player) entity;
-				if(this.y < player.getY()){
+				if(this.getY() < player.getY()){
 					this.newY += ySpeed;
 					this.setPosition(this.getX(), (int) newY);
-				}else if(this.y > player.getY()){
+				}else if(this.getY() > player.getY()){
 					this.newY -= ySpeed;
 					this.setPosition(this.getX(), (int) newY);
 				}

src/de/teamteamteam/spacescooter/entity/shot/Shot.java

@@ -46,7 +46,7 @@ public class Shot extends LivingEntity {
 		this.speed = shootSpeed;
 		this.damageValue = damageValue;
 		this.setImage(filename);
-		this.setPosition(this.x - this.getImage().getWidth() / 2, this.y - this.getImage().getHeight() / 2);
+		this.setPosition(this.getX() - this.getImage().getWidth() / 2, this.getY() - this.getImage().getHeight() / 2);
 	}
 
 	/**
@@ -68,11 +68,11 @@ public class Shot extends LivingEntity {
 	 * Remove the shot once out of the visible area.
 	 */
 	public void update() {
-		this.x += this.direction * this.speed;
+		this.transpose(this.direction * this.speed, 0);
 		//remove the shot in case it is out of the game window.
-		if ((this.x + this.getWidth()) < 0 || this.x > GameConfig.windowWidth
-				|| (this.y + this.getHeight()) < 0
-				|| this.y > GameConfig.windowHeight) {
+		if ((this.getX() + this.getWidth()) < 0 || this.getX() > GameConfig.windowWidth
+				|| (this.getY() + this.getHeight()) < 0
+				|| this.getY() > GameConfig.windowHeight) {
 			this.remove();
 		}
 	}