The bug in the Pong game

[Phoeenix]

Hello everyone,
I am new to this forum. I hope, i will contribute more as time passes.
I attached the program below. Everything seems fine but the program doesn't start working.
Any kind of contribution would be appreciated.
Thanks in advance.

Note: (From administration) The original author of the attached code requested an indication of his credit. The original code is said to be here. Please note that we did not check the code but found this request reasonable! This note is added to respect intellectual rights and to inform users of the forum.

[tim]

Hi Phoeenix, welcome to Java Forums!

I moved the code in the main() method to the frame's constructor. It works now. ;) Also, when extending components, be sure to call the super() constructor.

import java.io.*;
import java.awt.*;
import javax.swing.*;

public class Pong extends JFrame implements Runnable
{
	//Variables
	Thread pongThread; //Will be used to turn this runnable object into a working thread
	PongArena arena = new PongArena(400, 600); //Make a pong arena
	
	//Constructors
	public Pong()
	{
		super();
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //Tell it to close the program when the frame closes
		//Setup the layout and how things will be displayed...
		Container content = this.getContentPane();
		content.setLayout(new BorderLayout());
		content.add(arena, BorderLayout.CENTER);
		this.setTitle("Pong - By: Chris Canik");
		this.setResizable(false);
		
		//This tells the JFrame that it should resize according
		//to the component's (PongArena) prefered size
		this.pack();
		
		//The boundaries must be created here because getX and getY have no
		//accurate values when the arena's constructor is originally called
		arena.side1 = new PongArenaBoundary((int)(arena.getX() - 500),
											(int)(arena.getY() + arena.topPaddle.getHeight() + 30),
											(int)(500),
											(int)(arena.getBounds().getHeight() - arena.topPaddle.getHeight() - arena.bottomPaddle.getHeight() - 60));
		arena.side2 = new PongArenaBoundary((int)(arena.getX() + arena.getBounds().getWidth()),
											(int)(arena.getY() + arena.topPaddle.getHeight() + 30),
											(int)(arena.getX() + arena.getBounds().getWidth() + 500),
											(int)(arena.getBounds().getHeight() - arena.topPaddle.getHeight() - arena.bottomPaddle.getHeight() - 60));
		
		//Give the arena focus within the JPanel
		arena.requestFocus();
		
		setVisible(true); //Show the frame to the player

		//Turn this Runnable JPanel into an actual thread
		pongThread = new Thread(this);
		pongThread.start();
	}
	
	//Methods
	public void run()
	{
		boolean keepGoing = true; //Tracks whether there has not been an error
		
		while (keepGoing)
		{
			try
			{
				//Find out what the ball needs to bounce off of and do it
				arena.ball.bounce(arena.ball.needToBounce(arena));

			}
			catch (BallOffCourtException ex) //Point has been scored
			{
				//Make a new ball for a new round, and register it to
				//the two AI's so they don't try to follow the old one
				arena.topAI.registerBall(arena.newBall((arena.getWidth() / 2) - 10, (arena.getHeight() / 2) - 10, 20, 20));
				arena.bottomAI.registerBall(arena.ball);
				
			}
			
			//Display FPS in JPanel title
			this.setTitle("Pong (FPS: " + arena.fps.getFrames() + ") - By: Chris Canik");
			
			try
			{
				//Redraw everything and wait a bit as math is handled
				repaint();
				Thread.sleep(10); //(1000/10) = 100FPS
			}
			catch (InterruptedException ex)
			{
				//Error...  Time to stop running!
				System.out.println("Interrupted!");
				keepGoing = false;
			}
	}
	}
	
	//Main Method
	public static void main(String[] args)
	{
		Pong pongGame = new Pong(); //Lets make a game frame
	}

}

Very cool game, by the way. :D Glad to have you on the forum!

[Phoeenix]

Thank you ! Thank you ! Thank you!
You can't imagine how pleasent I am.

[Singing Boyo]

hmm... tim, isn't the super-constructor called implicitly? You only need to use super if you're calling a super-constructor with arguments.

e.g

public class Sub extends Super{
     public Sub(){

     }
}
//the above is equivalent to this:
public class Sub extends Super{
     public Sub(){
          super();
     }
}
//but this is different, and requires arguments to satisfy the super-constructor
public class Sub extends Super{
     public Sub(Object arg){
          super(arg);
     }
}

You don't ALWAYS need to call the super-constructor explicitly.

[tim]

Hey guys! :D

Thank you ! Thank you ! Thank you!
You can't imagine how pleasent I am.

It's my pleasure Phoeenix! Good luck with your other projects. ;)

hmm... tim, isn't the super-constructor called implicitly? You only need to use super if you're calling a super-constructor with arguments.

e.g

public class Sub extends Super{
     public Sub(){

     }
}
//the above is equivalent to this:
public class Sub extends Super{
     public Sub(){
          super();
     }
}
//but this is different, and requires arguments to satisfy the super-constructor
public class Sub extends Super{
     public Sub(Object arg){
          super(arg);
     }
}

You don't ALWAYS need to call the super-constructor explicitly.

Ah, okay. Didn't know that. Thank you Singing Boyo. ;)