问Java Swing问题

EN

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

public class DesktopSample {

  public static void main(final String[] args) {
    Runnable runner = new Runnable() {
      public void run() {
        try {
          UIManager.setLookAndFeel(
                  UIManager.getSystemLookAndFeelClassName());
        }
        catch (UnsupportedLookAndFeelException e) { }
        catch (ClassNotFoundException e) { }
        catch (InstantiationException e) { }
        catch (IllegalAccessException e) { }

        String title = (args.length==0 ? "Desktop Sample" : args[0]);
        JFrame frame = new JFrame(title);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JDesktopPane desktop = new JDesktopPane();
        JInternalFrame internalFrames[] = {
          new JInternalFrame("Can Do All", true, true, true, true),
          new JInternalFrame("Not Resizable", false, true, true, true),
          new JInternalFrame("Not Closable", true, false, true, true),
          new JInternalFrame("Not Maximizable", true, true, false, true),
          new JInternalFrame("Not Iconifiable", true, true, true, false)
        };

        InternalFrameListener internalFrameListener = new InternalFrameIconifyListener();

        int pos = 0;
        for(JInternalFrame internalFrame: internalFrames) {
          // Add to desktop
          desktop.add(internalFrame);

          // Position and size
          internalFrame.setBounds(pos*25, pos*25, 200, 100);
          pos++;

          // Add listener for iconification events
          internalFrame.addInternalFrameListener(internalFrameListener);

          JLabel label = new JLabel(internalFrame.getTitle(), JLabel.CENTER);
          internalFrame.add(label, BorderLayout.CENTER);

          // Make visible
          internalFrame.setVisible(true);
        }

        JInternalFrame palette = new JInternalFrame("Palette", true, false, true, false);
        palette.setBounds(350, 150, 100, 100);
        palette.putClientProperty("JInternalFrame.isPalette", Boolean.TRUE);
        desktop.add(palette, JDesktopPane.PALETTE_LAYER);
        palette.setVisible(true);

        desktop.setDragMode(JDesktopPane.OUTLINE_DRAG_MODE);

        frame.add(desktop, BorderLayout.CENTER);
        frame.setSize(500, 300);
        frame.setVisible(true);
      }
    };
    EventQueue.invokeLater(runner);
  }
}