Java - Table Tennis

// Game.java
Ball ball = new Ball(this);
    Ball1 ball1 = new Ball1(this);
    Racket racket = new Racket(this);

    public Game() {
        initComponents();
        new Thread(new Runnable(){
            @Override
            public void run() {
                while(true){
                    move();
                    table.repaint();

                    try {
                        Thread.sleep(10);
                    } catch (InterruptedException ex) {
                    }
                }
            }
        }).start();

        table.setFocusable(true);
    }

    void move(){
        ball.move();
        ball1.move();
        racket.move();

------

table = new javax.swing.JPanel(){
            public void paint(Graphics g){
                super.paint(g);
                ball.paint(g);
                ball1.paint(g);
                racket.paint(g);

            }

        };

-------

private void tableKeyPressed(java.awt.event.KeyEvent evt) {
        racket.keyPressed(evt);

    }

    private void tableKeyReleased(java.awt.event.KeyEvent evt) {
        racket.keyReleased(evt);
    }



// Racket.java
package exmay21;

import java.awt.Graphics;
import java.awt.event.KeyEvent;


public class Racket {

    Game game;

    int x = 0;
    int xMove = 0;

    Racket(Game game){
        this.game = game;
    }

    void paint(Graphics g){
        g.fillRect(x, game.getHeight()-50, 60, 10);
    }

    void move(){
        if(x+xMove > 0 && x+xMove < game.getWidth()-60)
        x=x+xMove;

    }

    void keyPressed(KeyEvent e){
        if(e.getKeyCode() == KeyEvent.VK_RIGHT)
            xMove = 1;
        if(e.getKeyCode() == KeyEvent.VK_LEFT)
            xMove = -1;

    }

    void keyReleased(KeyEvent e){
        xMove=0;
    }
}


// Ball.java
package tableTennis;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Rectangle;
import javax.swing.JOptionPane;

public class Ball {
    Tennis tennis;
    int x=0;
    int y=0;
    int xMove = 1;
    int yMove = 1;
    int sizeBall = 30;

    Color changeColor = Color.black;
    boolean visible;


    Ball(Tennis tennis){
        this.tennis=tennis;
        visible = true;
    }

    public void paint(Graphics g){
        g.setColor(changeColor);
        g.fillOval(x, y, 30, 30);
    }

    public boolean isVisible() {
        return visible;
    }

    public void setVisible(Boolean visible) {
        this.visible = visible;
    }

    void move(){
        if (x + xMove == 0) {
            changeColor = Color.black;
            xMove = 1;
        }
        if (x + xMove == tennis.getWidth() - 20) {
            changeColor = Color.black;
            xMove = -1;
        }
        if (y + yMove == 0) {
            yMove = 1;
            changeColor = Color.black;
        }
        if (y + yMove == tennis.getHeight() - 60) {
            yMove = -1;
            changeColor = Color.black;
        }

        if(collision()){
            System.out.println("Hit");
            //tennis.gameOver();
            sizeBall++;
            //setVisible(false);
            changeColor = Color.red;
        }

        x = x+xMove;
        y = y+yMove;
    }

    void remove(){
        x=-20;
        y=-20;
    }

    Rectangle getPosition(){
        return new Rectangle(x, y, 30, 30);
    }

    boolean collision(){
        return tennis.ball1.getPosition().intersects(getPosition());
    }
}