麻烦高手帮忙看下 为什么会出错?
import java.awt.EventQueue;import java.awt.event.*;import java.io.*;import javax.swing.*;public class ImageViewer{ public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { JFrame frame = new ImagerViewerFrame(); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setVisible(true); } });}}class ImagerViewerFrame extends JFrame{ public ImagerViewerFrame() { setTitle("ImageViewer"); setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT); label = new JLabel(); add(label); chooser = new JFileChooser(); chooser.setCurrentDirectory(new File(".")); 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 actionPerforme(ActionEvent event) { int result = chooser.showOpenDialog(null); 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;}