import java.util.List;
/**
 */
public class Ship extends Actor
{
    int speed = 5;
    int shotCounter = 0;
    private int delay = 0;
    private final int MAX_DELAY = 13;
    private int health = 3;

    /**
     * Method act: move spaceship 
     */
    public void act() 
    {
        move();   
        
        if(delay <= 0) {
            if( Greenfoot.isKeyDown("space") ) 
            {

                fire();
                Greenfoot.playSound("laser.wav");
                delay = MAX_DELAY;
            }
        }
        else {
            delay--;
        }

    }
   
    
    /**
     * Fire the laser
     */
    private void fire()
    {
        Shot shot = new Shot();
        getWorld().addObject(shot, getX(), getY());
        getWorld().addObject(shot, getX(), getY());
        shot.setRotation(getRotation());
    }    

    /**
     * Method move: checks for keystrokes and applies the changes, then moves the ship.
     * I applied a bit of slowing to the ship's speed (so it would be drifting to a stop)
     */
    private void move()
    {
        int dz = 0;
        if (Greenfoot.isKeyDown("d")) dz++;
        if (Greenfoot.isKeyDown("a")) dz--;
        setRotation(getRotation() + dz * 5);
        int ds = -1;
        if (Greenfoot.isKeyDown("w")) ds += 2;
        speed += ds;
        if (speed < 0) speed = 0;
        if (speed > 90) speed = 90;
        if (speed >= 200) move(speed / 100);
        if (Greenfoot.isKeyDown("s")) ds += 5;
        speed += ds;
        if (speed < 5) speed = 5;
        if (speed > 200) speed = 200;
        if (speed >= 20) move(speed / 10);

    }

   // private int health = 5; 
      
    public void setHealth(int points) {  
        health += points;  
    }  
    public int getHealth() {  
        return health;
    } 

}  
    

import greenfoot.*;  // (World, Actor, GreenfootImage, Greenfoot and MouseInfo)

/**
 * Write a description of class Enemylaser here.
 * 
 */
public class Redlaser extends Mover

{
   // private int life; 
    
    /**
     * Act - do whatever the Enemylaser wants to do. This method is called whenever
     * the 'Act' or 'Run' button gets pressed in the environment.
     */
     public void act()
     {
        move(20);
        eat();
        //life--;
       //if (life == 0)
      // {  
        //   getWorld().removeObject(this);  
       //}
       ifAtWorldEdge();
       hitEnemy();
     } 
     
    public void ifAtWorldEdge()  
    {  
        if (atWorldEdge())  
        {  
             getWorld().removeObject(this);  
        }  
    }
    
     
    public void eat()
    {
        //Actor Ship;
        //Ship = getOneObjectAtOffset(0, 0, Ship.class);
        
       // if (Ship != null)
       // {
          //  World World;
          //  World = getWorld();
          //  GameOver gameover = new GameOver();
          //  World.addObject(gameover, World.getWidth()/2, World.getHeight()/2);
          //  World.removeObject(Ship);
            
        //} 
        
       //  if (Ship != null)
       // {
        //    World world;
        //    world = getWorld();
        //    world.removeObject(Ship);
        //    GameOver gameover = new GameOver();
       // }
        
              
        Actor BigRock;
        BigRock = getOneObjectAtOffset(0, 0, BigRock.class);
        if (BigRock != null)
        {
            World world;
            world = getWorld();
            world.removeObject(BigRock);
        } 
    }
    
    //in your bullet class you have to add this method:  
public void hitEnemy() {  
    Ship ship = (Ship) getOneObjectAtOffset(0, 0, Ship.class);  
    if (ship != null) {  
        ship.setHealth(-1);//decrements the health of this enemy;  
        //if you want your bullet to be removed now you have to add the next line; otherwhise delete it.  
        //getWorld().removeObject(this);
         if(ship.getHealth()==0) {getWorld().removeObject(this);}
    }  
}  
}   
    
    

if(getHealth()==0) {getWorld().removeObject(this);} 

ship.setHealth(); //your new call

setHealth()
{health--;} //your new method

if (life == 0 || atWorldEdge() || hitEnemy()) getWorld().removeObject(this);