Need help with pong semester project

[ResidentBiscuit]

Hey all so I'm making a pong game for my semester project. Currently, I'm just trying to get the basic engine up and running for it. I have no experience with graphics or windows programming before this so its all news to me. Well, I was going along, made my ball class and created an object and drew it on the screen. It displayed (even though not in the spot it should have), and then I went along adding some collision detection and ball movement, and now my ball disappeared! I tried commenting out the new code to no avail, not sure what happened but I will post my code and you can look at it!

	
package Pong;
import java.awt.*;
import java.awt.image.BufferStrategy;
 
import javax.swing.JFrame;
public class Game extends JFrame {
      
    /**
     * 1 player Pong-type game programmed by
     * Jared Ready and Jake Saile.
     */
  
    //Variable and object declaration
    //windowWidth and windowHeight are used for the game window resolution
    private int windowWidth = 800;
    private int windowHeight = 600;
    private Ball ball;
  
  
    public static void main(String[] args) {
        new Game();
    }
  
    //Constructor for class Game. Sets up attributes for the game window.
    public Game() {
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setSize(windowWidth, windowHeight);
        this.setResizable(false);
        this.setLocation(100, 100);
        this.setVisible(true);
  
        //Creates a buffer strategy with 2 buffers. Gets rid of screen flickering that would
        //occur without
        this.createBufferStrategy(2);
  
        initGame();
  
        while(true) {
            long start = System.currentTimeMillis();
            gameLoop();
            while(System.currentTimeMillis()-start < 5) {
                 //do nothing
            }
        }
    }
  
     
    //This initializes all variables and objects needed for Game class
    private void initGame() {
        ball = new Ball(windowWidth/2, windowHeight/2, 1,-1, 40);
    }
  
     
    //This is the method that handles the logic of the game
    private void gameLoop() {
         
        //We need to start with moving the ball to its new position
        ball.posX = ball.posX + ball.speedX;
        ball.posY = ball.posY + ball.speedY;
         
        //Checks for wall collision, and changes movement of ball if need be
        if(ball.posX <= 0 || ball.posX >= windowWidth - ball.ballSize)
            ball.speedX = -ball.speedX;
        if(ball.posY <= 0)
            ball.speedY = -ball.speedY;
         
        drawFrame();
    }
  
    private void drawFrame() {
        //draws the updated frame
        BufferStrategy buffer = this.getBufferStrategy();
        Graphics graphics = null;
  
        try {
            graphics = buffer.getDrawGraphics();
  
            //Clears the back buffer by just making it black
            graphics.setColor(Color.BLACK);
            graphics.fillRect(0, 0, windowWidth, windowHeight);
            drawBall(graphics);
        } finally {
            //Destroys graphics object not being used now
            graphics.dispose();
        }
  
        //Switches to display the back buffer
        buffer.show();
  
        //This tells the system to synchronize the state of the graphics so that the
        //display is up to date
        Toolkit.getDefaultToolkit().sync();
    }
     
    //Draws ball on the screen at the middle
    public void drawBall(Graphics graphics)
    {
        graphics.setColor(Color.RED);
        graphics.fillOval(ball.posX, ball.posY, ball.ballSize, ball.ballSize);
    }
}

package Pong;
 
public class Ball {
     
    /**
     * Class for holding our Ball object.
     * Just holds the dimensions and speed of the ball
     */
     
    //Using public variables currently for ease of use
    //when drawing the ball
     
    //Speed
    public int speedX;
    public int speedY;
     
    //Start position
    public int posX;
    public int posY;
     
    //Size
    public int ballSize;
     
     
    //Contructor for the Ball class.
    //Parameters (position x, position y, speed on x axis, speed on y axis, size of ball)
    public Ball(int posX, int posY, int speedX, int speedY, int ballSize)
    {
        posX = this.posX;
        posY = this.posY;
        speedX = this.speedX;
        speedY = this.speedY;
        ballSize = this.ballSize;
    }

[KevinWorkman]

Try printing out the ball's position each frame to see where it is?

[ResidentBiscuit]

I did try that, the coordinates always remain at (0,0) and the I made a print for the variables, also at (0,0)

[KevinWorkman]

Ah, I see. Look in Ball's constructor. What do you think those statements are doing? Check your assumptions.

Also, to do painting, you might want to follow this tutorial: Lesson: Performing Custom Painting (The Java™ Tutorials > Creating a GUI With JFC/Swing)

[ResidentBiscuit]

In my constructor? I think it's setting the variables for the object to whatever was passed into the constructor? Am I wrong?

[ResidentBiscuit]

Oh wow! Thank you so much! I guess I misunderstood the this keyword. I THOUGHT it referred to the closest item with that name, ie. the most "local" one to it. So I thought it would be referring to the variable created in the constructor. Once again, thank you so much! I've been stuck for a couple days just because of that problem. Now I have a bouncing ball program :)