请高手帮看看以下错误通常是如何造成的...
Exception in thread "main" java.lang.NoClassDefFoundError: bounce (wrong name: B
ounce)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:12
4)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
Exception in thread "main" java.lang.NoClassDefFoundError: bounce (wrong name: B
ounce)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:12
4)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
%SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem;C:\Program Files\Microsoft SQL Server\80\Tools\BINN;C:\Program Files\Microsoft SQL Server\90\Tools\binn\;C:\Program Files\Gemplus\GemSafe Libraries\BIN;E:\donesoft\jdk1.5\bin;E:\donesoft\jdk1.5\jre\bin;E:\donesoft\jdk1.5\lib;代码上不来,被我这边的内网限制了...引入以下包:
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.util.*;
import javax.swing.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.util.*;
import javax.swing.*;/**
Shows an animated bouncing ball.
*/
public class Bounce
{
public static void main(String[] args)
{
JFrame frame = new BounceFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.show();
}
}/**
The frame with canvas and buttons.
*/
class BounceFrame extends JFrame
{
/**
Constructs the frame with the canvas for showing the
bouncing ball and Start and Close buttons
*/
public BounceFrame()
{
setSize(WIDTH, HEIGHT);
setTitle("Bounce");Container contentPane = getContentPane();
canvas = new BallCanvas();
contentPane.add(canvas, BorderLayout.CENTER);
JPanel buttonPanel = new JPanel();
addButton(buttonPanel, "Start",
new ActionListener()
{
public void actionPerformed(ActionEvent evt)
{
addBall();
}
});
new ActionListener()
{
public void actionPerformed(ActionEvent evt)
{
System.exit(0);
}
});
contentPane.add(buttonPanel, BorderLayout.SOUTH);
}/**
Adds a button to a container.
@param c the container
@param title the button title
@param listener the action listener for the button
*/
public void addButton(Container c, String title,
ActionListener listener)
{
JButton button = new JButton(title);
c.add(button);
button.addActionListener(listener);
}/**
Adds a bouncing ball to the canvas and makes
it bounce 1,000 times.
*/
public void addBall()
{
try
{
Ball b = new Ball(canvas);
canvas.add(b);for (int i = 1; i <= 1000; i++)
{
b.move();
Thread.sleep(5);
}
}
catch (InterruptedException exception)
{
}
}
public static final int WIDTH = 450;
public static final int HEIGHT = 350;
}/**
The canvas that draws the balls.
*/
class BallCanvas extends JPanel
{
/**
Add a ball to the canvas.
@param b the ball to add
*/
public void add(Ball b)
{
balls.add(b);
}public void paintComponent(Graphics g)
{
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;
for (int i = 0; i < balls.size(); i++)
{
Ball b = (Ball)balls.get(i);
b.draw(g2);
}
}private ArrayList balls = new ArrayList();
}/**
A ball that moves and bounces off the edges of a
component
*/
class Ball
{
/**
Constructs a ball in the upper left corner
@c the component in which the ball bounces
*/
public Ball(Component c) { canvas = c; }/**
Draws the ball at its current position
@param g2 the graphics context
*/