import java.awt.EventQueue;
import java.awt.event.*;
import java.io.*;
import javax.swing.*;/**
* A program for viewing images.
* @version 1.22 2007-05-21
* @author Cay Horstmann
*/
public class ImageViewer
{
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
JFrame frame = new ImageViewerFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
});
}
}/**
* A frame with a label to show an image.
*/
class ImageViewerFrame extends JFrame
{
public ImageViewerFrame()
{
setTitle("ImageViewer");
setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT); // use a label to display the images
label = new JLabel();
add(label); // set up the file chooser
chooser = new JFileChooser();
chooser.setCurrentDirectory(new File(".")); // set up the menu bar
JMenuBar menuBar = new JMenuBar();
setJMenuBar(menuBar); JMenu menu = new JMenu("File");
menuBar.add(menu); JMenuItem openItem = new JMenuItem("Open");
menu.add(openItem);
openItem.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
// show file chooser dialog
int result = chooser.showOpenDialog(null); // if file selected, set it as icon of the label
if (result == JFileChooser.APPROVE_OPTION)
{
String name = chooser.getSelectedFile().getPath();
label.setIcon(new ImageIcon(name));
}
}
}); JMenuItem exitItem = new JMenuItem("Exit");
menu.add(exitItem);
exitItem.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
System.exit(0);
}
});
} private JLabel label;
private JFileChooser chooser;
private static final int DEFAULT_WIDTH = 300;
private static final int DEFAULT_HEIGHT = 400;
}
import java.awt.event.*;
import java.io.*;
import javax.swing.*;/**
* A program for viewing images.
* @version 1.22 2007-05-21
* @author Cay Horstmann
*/
public class ImageViewer
{
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
JFrame frame = new ImageViewerFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
});
}
}/**
* A frame with a label to show an image.
*/
class ImageViewerFrame extends JFrame
{
public ImageViewerFrame()
{
setTitle("ImageViewer");
setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT); // use a label to display the images
label = new JLabel();
add(label); // set up the file chooser
chooser = new JFileChooser();
chooser.setCurrentDirectory(new File(".")); // set up the menu bar
JMenuBar menuBar = new JMenuBar();
setJMenuBar(menuBar); JMenu menu = new JMenu("File");
menuBar.add(menu); JMenuItem openItem = new JMenuItem("Open");
menu.add(openItem);
openItem.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
// show file chooser dialog
int result = chooser.showOpenDialog(null); // if file selected, set it as icon of the label
if (result == JFileChooser.APPROVE_OPTION)
{
String name = chooser.getSelectedFile().getPath();
label.setIcon(new ImageIcon(name));
}
}
}); JMenuItem exitItem = new JMenuItem("Exit");
menu.add(exitItem);
exitItem.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
System.exit(0);
}
});
} private JLabel label;
private JFileChooser chooser;
private static final int DEFAULT_WIDTH = 300;
private static final int DEFAULT_HEIGHT = 400;
}
F:\Java基础练习\25>javac ImageViewer.java
Exception in thread "main" java.lang.NoClassDefFoundError: com/sun/tools/javac/M
ain
Caused by: java.lang.ClassNotFoundException: com.sun.tools.javac.Main
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)F:\Java基础练习\25>
我在命令行下搞的。