Pong in Java (CLASS)

/*
 * This code is protected under the Gnu General Public License (Copyleft), 2005 by
 * IBM and the Computer Science Teachers Association. It may be freely
 * modified and redistributed under educational fair use.
 */

import csta.ibm.pong.Game;

public class Pong extends Game
{
    // Add any state variables or object references here
    Ball b = new Ball();
    Paddle p1 = new Paddle();
    Paddle p2 = new Paddle();

    private static int ballSize;
    private static int paddleHeight;
    private static int width;

    private static int x, y;

    /**
     * Fill in this method with code that tells the game what to do
     * before actual play begins
     */
    public void setup()
    {
        ballSize = 10;
        paddleHeight = 10;
        width = 100;

        b.setColor(java.awt.Color.red);
        p1.setColor(java.awt.Color.green);
        p2.setColor(java.awt.Color.green);

        b.setX(185);
        b.setY(150);
        p1.setX(0);
        p1.setY(145);
        p2.setX(375);
        p2.setY(145);

        b.setSize(10, 10);
        p1.setSize(10, 50);
        p2.setSize(10, 50);

        add(b);
        add(p1);
        add(p2);

        setBackground(java.awt.Color.blue);

        getContentPane().repaint();
    }

    /**
     * Fill in this method with code that tells the playing field what to do
     * from one moment to the next
     */
    public void act()
    {
        if(ZKeyPressed())
        {
            p1.moveUp();
        }
        if(XKeyPressed())
        {
            p1.moveDown();
        }
        if(MKeyPressed())
        {
            p2.moveUp();
        }
        if(NKeyPressed())
        {
            p2.moveDown();
        }
        getContentPane().repaint();
    }

    // Add any additional methods here

    /**
     * This code has been provided for you, and should not be modified
     */
    public static void main(String[] args)
    {
        Pong p = new Pong();
        p.setVisible(true);
        p.initComponents();
    }
}

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/*
 * This code is protected under the Gnu General Public License (Copyleft), 2005 by
 * IBM and the Computer Science Teachers Association. It may be freely
 * modified and redistributed under educational fair use.
 */

import csta.ibm.pong.GameObject;

public class Paddle extends GameObject
{
    // Add any state variables here

    /**
     * Fill in this method with code that describes the behavior
     * of a paddle from one moment to the next
     */
    public void act()
    {

    }

    // Add any additional methods here
    public void moveUp()
    {
       setY(5);
    }

    public void moveDown()
    {
      setY(-5);
    }
}

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/*
 * This code is protected under the Gnu General Public License (Copyleft), 2005 by
 * IBM and the Computer Science Teachers Association. It may be freely
 * modified and redistributed under educational fair use.
 */

import csta.ibm.pong.GameObject;

public class Ball extends GameObject
{
    // Add any state variables here
    private static int xVelocity;
    private static int yVelocity;

    private static int MAXX;
    private static int MAXY;

    int randomNumber;

    /**
     * Fill in this method with code that describes the behavior
     * of a ball from one moment to the next
     */
    public void act()
    {

    }

    // Add any additional methods here
}