komputer grafik.

/** UNIVERSITA INDRAPRASTA PGRI
animasi bola melenting.
*/
/** UNIVERSITA INDRAPRASTA PGRI

animasi bola melenting.

*/

import java.awt.*;

import java.awt.event.*;
import java.awt.geom.*;
import java.util.*;
import javax.swing.*;
/**
Menampilkan animasi bola melenting.
*/
public class Bouncing
{
public static void main(String[] args)
{
JFrame frame = new BounceFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
// kelas runnable yang melaksanakan animasi.
class BallRunnable implements Runnable
{
// Constructor darirunnable.
public BallRunnable(Ball aBall, Component aComponent)
{
ball = aBall;
component = aComponent;
}
// fungsi yang menjalankan animasi
public void run()
{


try
{
for (int i = 1; i <= STEPS; i++) { ball.move(component.getBounds()); component.repaint(); Thread.sleep(DELAY); } } catch (InterruptedException e) { } } private Ball ball; private Component component; public static final int STEPS = 1000; public static final int DELAY = 5; } /** kelas ball yang menggerakkan bola dan melenting ketika nabrak dinding */ class Ball { /** pindahkan bola ke posisi berikutnya ubah arahnya ketika nabrak dinding */ public void move(Rectangle2D bounds) { x += dx; y += dy; if (x < bounds.getMinX()) { x = bounds.getMinX(); dx = -dx; } if (x + XSIZE >= bounds.getMaxX())
{
x = bounds.getMaxX() - XSIZE;
dx = -dx;
}
if (y < bounds.getMinY()) { y = bounds.getMinY(); dy = -dy; } if (y + YSIZE >= bounds.getMaxY())
{
y = bounds.getMaxY() - YSIZE;
dy = -dy;
}
}
/**
Membentuk bola dan posisi-nya.
*/
public Ellipse2D getShape()
{
return new Ellipse2D.Double(x, y, XSIZE, YSIZE);
}
private static final int XSIZE = 15;
private static final int YSIZE = 15;
private double x = 0;
private double y = 0;
private double dx = 1;
private double dy = 1;
}
// panel tempat bola .
class BallPanel extends JPanel
{
// pasang bola di panel
public void add(Ball b)
{
balls.add(b);
}
public void paintComponent(Graphics g)
{
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
for (Ball b : balls)
{
g2.fill(b.getShape());
}
}
private ArrayList balls = new ArrayList();
}
/**
The frame with panel and buttons.
*/
class BounceFrame extends JFrame
{
public BounceFrame()
{
setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
setTitle("BounceThread");
panel = new BallPanel();
add(panel, BorderLayout.CENTER);
JPanel buttonPanel = new JPanel();
addButton(buttonPanel, "Start",
new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
addBall();
}
});
addButton(buttonPanel, "Close",
new ActionListener()

{
public void actionPerformed(ActionEvent event)
{
System.exit(0);
}
});
add(buttonPanel, BorderLayout.SOUTH);
}
public void addButton(Container c, String title, ActionListener listener)
{
JButton button = new JButton(title);
c.add(button);
button.addActionListener(listener);
}
public void addBall()
{
Ball b = new Ball();
panel.add(b);
Runnable r = new BallRunnable(b, panel);
Thread t = new Thread(r);
t.start();
}
private BallPanel panel;
public static final int DEFAULT_WIDTH = 450;
public static final int DEFAULT_HEIGHT = 350;
public static final int STEPS = 1000;
public static final int DELAY = 3;
}



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