Pong

package games.complete;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Toolkit;

import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.Arrays;

import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class Pong
{
    JFrame frame;
    JPanel mainPanel;

    Ball ball;

    Paddle player;
    Paddle enemy;

    MoveController mc = new MoveController();
    DisplayManager dm = new DisplayManager();

    int maxSpeed = 5;
    double movement = 1;

    public static void main(String[] args)
    {
        new Pong();
    }

    public Pong()
    {
        frame = new JFrame("Pong");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        mainPanel = new JPanel(null);

        mainPanel.setBackground(Color.black);
        mainPanel.setPreferredSize(new Dimension(500, 500));

        player = new Paddle(20, 100);
        enemy = new Paddle(20, 100);
        ball = new Ball(5, Color.GREEN);

        mainPanel.add(player);
        mainPanel.add(enemy);
        mainPanel.add(ball);
        enemy.setColor(Color.RED);

        frame.setContentPane(mainPanel);
        frame.pack();

        Dimension screen = Toolkit.getDefaultToolkit().getScreenSize();
        int x = screen.width/2 - frame.getWidth()/2;
        int y = screen.height/2 - frame.getHeight()/2;
        frame.setLocation(x, y);

        mainPanel.addKeyListener(mc);

        frame.setVisible(true);

        mainPanel.repaint();

        x = mainPanel.getWidth()/2 - ball.getWidth()/2;
        y = mainPanel.getHeight()/2 - ball.getHeight()/2;
        System.out.println("X: " + x + ", Y: " + y);
        ball.setLocation(x, y);

        x = 0;
        y = mainPanel.getHeight()/2 - player.getHeight()/2;
        System.out.println("X: " + x + ", Y: " + y);
        player.setLocation(x, y);

        x = mainPanel.getWidth() - enemy.getWidth();
        y = mainPanel.getHeight()/2 - enemy.getHeight()/2;
        System.out.println("X: " + x + ", Y: " + y);
        enemy.setLocation(x, y);

        System.out.println(Arrays.deepToString(mainPanel.getComponents()));

        mainPanel.repaint();

        frame.addMouseListener(new MouseAdapter()
        {
            @Override
            public void mousePressed(MouseEvent e)
            {
                mainPanel.requestFocus();
            }
        });

        dm.start();
        mainPanel.requestFocus();
    }

    private class Ball extends JComponent
    {
        private int radius;
        private Color color;

        public Ball(int size, Color c)
        {
            if(size > 0)
                radius = size;
            else
                radius = 1;
            this.setPreferredSize(new Dimension(radius, radius));
            color = c;
        }

        public Ball(int size)
        {
            this(size, Color.RED);
        }

        public Color getColor()
        {
            return color;
        }

        public void setColor(Color c)
        {
            color = c;
        }

        public int getRadius()
        {
            return radius;
        }

        public void setRadius(int r)
        {
            radius = r > 0 ? r : radius;
        }

        @Override
        public void paintComponent(Graphics g)
        {
            System.out.println("Radius: " + radius);
            g.setColor(color);
            g.fillOval(0, 0, radius, radius);
        }

        @Override
        public String toString()
        {
            return "games.common.Pong.Ball[Radius=" + radius + ",Color="+color.toString()+"]";
        }
    }

    private class Paddle extends JComponent
    {
        private int width;
        private int height;
        private Color color;

        public double vx;
        public double vy;

        public Paddle(int width, int height, Color c)
        {
            this.width = width > 0 ? width : 1;
            this.height = height > 0 ? height : 1;
            this.setPreferredSize(new Dimension(width, height));
            color = c;
        }

        public Paddle(int width, int height)
        {
            this(width, height, Color.BLUE);
        }

        public int getHeight()
        {
            return height;
        }

        public int getWidth()
        {
            return width;
        }

        public void setHeight(int h)
        {
            height = h > 0 ? h : height;
        }

        public void setWidth(int w)
        {
            width = w > 0 ? w : width;
        }

        public Color getColor()
        {
            return color;
        }

        public void setColor(Color c)
        {
            color = c;
        }

        @Override
        public void paintComponent(Graphics g)
        {
            g.setColor(color);
            g.fillRect(0, 0, width, height);
        }
    }

    private class DisplayManager extends Thread
    {
        public DisplayManager()
        {
            super(new Runnable() {

                boolean paused;
                boolean run;

                @Override
                public void run()
                {
                    while(true)
                    {
                        mainPanel.repaint();

                        player.setLocation(player.getX(), (int)Math.round(player.getY() + player.vy));
                        enemy.setLocation(enemy.getX(), (int)Math.round(enemy.getY() + enemy.vy));

                        if(player.getY() < 0)
                        {
                            player.setLocation(player.getX(), 0);
                            player.vy = 0;
                        }

                        if(player.getY() > mainPanel.getHeight() - player.getHeight())
                        {
                            player.setLocation(player.getX(), mainPanel.getHeight() - player.getHeight());
                            player.vy = 0;
                        }

                        if(enemy.getY() < 0)
                        {
                            enemy.setLocation(enemy.getX(), 0);
                            player.vy = 0;
                        }

                        if(enemy.getY() > mainPanel.getHeight() - enemy.getHeight())
                        {
                            enemy.setLocation(enemy.getX(), mainPanel.getHeight() - enemy.getHeight());
                            player.vy = 0;
                        }

                        if(player.vy > maxSpeed)
                            player.vy = maxSpeed;
                        if(player.vy < -maxSpeed)
                            player.vy = -maxSpeed;
                        if(enemy.vy > maxSpeed)
                            enemy.vy = maxSpeed;
                        if(enemy.vy < -maxSpeed)
                            enemy.vy = -maxSpeed;

                        try
                        {
                            Thread.sleep(1000/60);
                        }
                        catch(InterruptedException ex)
                        {

                        }

                        player.vy *= 0.98;
                    }
                }
            });
        }
    }

    private class MoveController implements KeyListener
    {
        @Override
        public void keyTyped(KeyEvent e) {
        }

        @Override
        public void keyPressed(KeyEvent e)
        {
            switch(e.getKeyCode())
            {
                case KeyEvent.VK_UP: case KeyEvent.VK_W:
                    player.vy -= movement;
                    break;
                case KeyEvent.VK_DOWN: case KeyEvent.VK_S:
                    player.vy += movement;
                    break;
                default:
                    System.out.println("You're not doing it right!");
            }
            System.out.println("VX: " + player.vx + ", VY: " + player.vy);
        }

        @Override
        public void keyReleased(KeyEvent e) {
        }

    }
}