JAVA

mport java.util.List; import java.util.ArrayList;

/**

* Wombat. A Wombat moves forward until it can't do so anymore, at
* which point it turns left. If a wombat finds a leaf, it eats it.
* 
* @author Michael Kolling
* @version 1.0.1
*/

public class Wombat extends Actor {

   private static final int EAST = 0;
   private static final int WEST = 1;
   private static final int NORTH = 2;
   private static final int SOUTH = 3;

   private int direction;
   private int leavesEaten;

   public Wombat()
   {
       setDirection(EAST);
       leavesEaten = 0;
   }

   /**
    * Do whatever the wombat likes to to just now.
    */
   public void act()
   {
       if(foundLeaf()) {
           eatLeaf();
       }
       else if(canMove()) {
           move();
       }
       else {
           turnLeft();
       }
   }

   /**
    * Check whether there is a leaf in the same cell as we are.
    */
   public boolean foundLeaf()
   {
       Actor leaf = getOneObjectAtOffset(0, 0, Leaf.class);
       if(leaf != null) {
           return true;
       }
       else {
           return false;
       }
   }
   
   /**
    * Eat a leaf.
    */
   public void eatLeaf()
   {
       Actor leaf = getOneObjectAtOffset(0, 0, Leaf.class);
       if(leaf != null) {
           // eat the leaf...
           getWorld().removeObject(leaf);
           leavesEaten = leavesEaten + 1; 
       }
   }
   
   /**
    * Move one cell forward in the current direction.
    */
   public void move()
   {
       if (!canMove()) {
           return;
       }
       switch(direction) {
           case SOUTH :
               setLocation(getX(), getY() + 1);
               break;
           case EAST :
               setLocation(getX() + 1, getY());
               break;
           case NORTH :
               setLocation(getX(), getY() - 1);
               break;
           case WEST :
               setLocation(getX() - 1, getY());
               break;
       }
   }

   /**
    * Test if we can move forward. Return true if we can, false otherwise.
    */
   public boolean canMove()
   {
       World myWorld = getWorld();
       int x = getX();
       int y = getY();
       switch(direction) {
           case SOUTH :
               y++;
               break;
           case EAST :
               x++;
               break;
           case NORTH :
               y--;
               break;
           case WEST :
               x--;
               break;
       }
       // test for outside border
       if (x >= myWorld.getWidth() || y >= myWorld.getHeight()) {
           return false;
       }
       else if (x < 0 || y < 0) {
           return false;
       }
       return true;
   }

   /**
    * Turns towards the left.
    */
   public void turnLeft()
   {
       switch(direction) {
           case SOUTH :
               setDirection(EAST);
               break;
           case EAST :
               setDirection(NORTH);
               break;
           case NORTH :
               setDirection(WEST);
               break;
           case WEST :
               setDirection(SOUTH);
               break;
       }
   }

   /**
    * Sets the direction we're facing.
    */
   public void setDirection(int direction)
   {
       this.direction = direction;
       switch(direction) {
           case SOUTH :
               setRotation(90);
               break;
           case EAST :
               setRotation(0);
               break;
           case NORTH :
               setRotation(270);
               break;
           case WEST :
               setRotation(180);
               break;
           default :
               break;
       }
   }

   /**
    * Tell how many leaves we have eaten.
    */
   public int getLeavesEaten()
   {
       return leavesEaten;
   }

}