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package colorfulbouncingcircle;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileNotFoundException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Scanner;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;

import javax.swing.*;
import java.awt.*;
import java.util.ArrayList;

public class ColorfulBouncingCircle {
    
    public double setPlayingFieldSize( int x, int y){
       double v;
       v=2+x+y;
       return v;
    }

    /**setPlayingFieldSize (double newWidth, double newHeight){}
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        PlayingField playingField = new PlayingField();
        playingField.run();
    }
    
}

class PlayingField {
    
   private ColorfulBouncingCircle objA = new ColorfulBouncingCircle ( );
    public void b1 ( ) {
        // Call to method a1. This works.
        objA.setPlayingFieldSize (640,480);
    
    }
    JFrame frame = new JFrame("InputDialog Example #1");

    // prompt the user to enter their name
    String mywidth = JOptionPane.showInputDialog(frame, "What Window width?");
    String myheight = JOptionPane.showInputDialog(frame, "What window height?");
   int w = Integer.parseInt(mywidth);
   int h = Integer.parseInt(myheight);
    
    private JFrame mainFrame;
    private DrawPanel drawPanel;
    private java.util.List<Ball> allCircles;

    private int windowWidth = w;
    private int windowHeight = h;
    private String windowLabel = "ColourfulBouncingCircles";

    void run() {

        allCircles = new ArrayList<>();

        /* Generate allCircles */
        for (int i = 0; i < 50; i++) {
            Ball ball = new Ball(
                    /* Random positions from 0 to windowWidth or windowHeight */
                    (int) Math.floor(Math.random() * windowWidth),
                    (int) Math.floor(Math.random() * windowHeight),
                    /* Random size from 10 to 30 */
                    (int) Math.floor(Math.random() * 20) + 10,
                    /* Random RGB colors*/
                    new Color(
                            (int) Math.floor((Math.random() * 256)),
                            (int) Math.floor((Math.random() * 256)),
                            (int) Math.floor((Math.random() * 256))
                    ),
                    /* Set velocities */
                    (int) Math.floor((Math.random() * 10) - 5),
                    (int) Math.floor((Math.random() * 10) - 5)
            );

            allCircles.add(ball);
        }

        /* Initialize program */
        mainFrame = new JFrame();
        drawPanel = new DrawPanel();
        mainFrame.getContentPane().add(drawPanel);
        mainFrame.setTitle(windowLabel);
        mainFrame.setSize(windowWidth, windowHeight);
        mainFrame.setVisible(true);
        mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        while (true) {
            for (Ball b: allCircles) {
                b.update();
            }

            /* Give Swing 10 milliseconds to see the update! */
            try {
                Thread.sleep(10);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }

            mainFrame.repaint();
        }
    }

    class DrawPanel extends JPanel {
        @Override
        public void paintComponent(Graphics graphics) {
            super.paintComponent(graphics);

            for (Ball b: allCircles) {
                b.draw(graphics);
            }

        }
    }

    class Ball {
        private int posX, posY, size;
        private Color color;

        private int vx = 5;
        private int vy = 5;

        public Ball(int posX, int posY, int size, Color color, int vx, int vy) {
            this.posX = posX;
            this.posY = posY;
            this.size = size;
            this.color = color;
            this.vx = vx;
            this.vy = vy;
        }

        void update() {

            if (posX > mainFrame.getWidth() || posX < 0) {
                vx *= -1;
            }

            if (posY > mainFrame.getHeight() || posY < 0) {
                vy *= -1;
            }

            if (posX > mainFrame.getWidth()) {
                posX = mainFrame.getWidth();
            }

            if (posX < 0) {
                posX = 0;
            }

            if (posY > mainFrame.getHeight()) {
                posY = mainFrame.getHeight();
            }

            if (posY < 0) {
                posY = 0;
            }

            this.posX += vx;
            this.posY += vy;

        }

        void draw(Graphics g) {
            g.setColor(color);
            g.fillOval(posX, posY, size, size);
        }
    }
}