Image + Mouse Movement

[YM]

Ok So I am attempting to make a space shooter game, so far this is my code, I was able to make the image print to screen in a program seperate from the mouse portion of the program, although when I try to combine them I get a nullpointexception.

Once I finish this I was just going to learn how to do collision detecting between two images (bad guys and ur ship) and then create a random x integer for the bad guys to come on the screen using Math.random and then create a loop with prints ur ship, the baddies (moving towards u) and the score on the screen...

once i got that if i still have time I am going to add bullets coming from the ship to kill em enemies instead of simply dodging them

code:

import java.applet.*; import java.awt.*; import java.awt.event.*; import java.net.*; public class Mouse2 extends Applet     implements MouseListener, MouseMotionListener {     int width, height;     int mx, my;  // the mouse coordinates     boolean isButtonPressed = false;     public void init ()     {         width = getSize ().width;         height = getSize ().height;         mx = width / 2;         my = height / 2;         addMouseListener (this);         addMouseMotionListener (this);     }     public void mouseEntered (MouseEvent e)     {         // called when the pointer enters the applet's rectangular area     }     public void mouseExited (MouseEvent e)     {         // called when the pointer leaves the applet's rectangular area     }     public void mouseClicked (MouseEvent e)     {         // called after a press and release of a mouse button         // with no motion in between         // (If the user presses, drags, and then releases, there will be         // no click event generated.)     }     public void mousePressed (MouseEvent e)     { // called after a button is pressed down         isButtonPressed = true;         repaint ();         // "Consume" the event so it won't be processed in the         // default manner by the source which generated it.         e.consume ();     }     public void mouseReleased (MouseEvent e)     { // called after a button is released         isButtonPressed = false;         repaint ();         e.consume ();     }     public void mouseMoved (MouseEvent e)     { // called during motion when no buttons are down         mx = e.getX ();         my = e.getY ();         showStatus ("Mouse at (" + mx + "," + my + ")");         repaint ();         e.consume ();     }     public void mouseDragged (MouseEvent e)     { // called during motion with buttons down         mx = e.getX ();         my = e.getY ();         showStatus ("Mouse at (" + mx + "," + my + ")");         repaint ();         e.consume ();     }     Image my_gif;     URL base;     MediaTracker mt;     public void init1 ()     {         mt = new MediaTracker (this);         try         {             base = getDocumentBase ();         }         catch (Exception e)         {         }         my_gif = getImage (getDocumentBase(), "ship.gif");         mt.addImage (my_gif, 1);         try         {             mt.waitForAll ();         }         catch (InterruptedException e)         {         }     }     public void paint (Graphics g)     {  g.drawImage( my_gif, mx, my, this );       //  g.fillRect (mx,my,20,20);     } }

not sure what the program is here