Java给JFrame窗口设置热键的方法实现

public class MyNotepad extends JFrame{
 //菜单栏
 private JMenuBar jmb = new JMenuBar();
 //菜单
 private JMenu jmFile = new JMenu("文件(F)");
 private JMenu jmEdit = new JMenu("编辑(E)");
 private JMenu jmFormat = new JMenu("格式(O)");
 private JMenu jmFind = new JMenu("查看(V)");
 private JMenu jmHelp = new JMenu("帮助(H)");

//菜单项
private JMenuItem jmiNew = new JMenuItem("新建");
private JMenuItem jmiOpen = new JMenuItem("打开");
private JMenuItem jmiSave = new JMenuItem("保存");
private JMenuItem jmiOther = new JMenuItem("另存为");
private JMenuItem jmiExit = new JMenuItem("退出(X)");


private JCheckBoxMenuItem jmiAutoLine = new JCheckBoxMenuItem("自动换行");
private JMenuItem jmiFont = new JMenuItem("字体");

private JFileChooser jfc = new JFileChooser();

private JTextArea jta = new JTextArea();
private JScrollPane jsp = new JScrollPane(jta);

//上下文菜单
private JPopupMenu jpm = new JPopupMenu();
private JMenuItem jmiCopy = new JMenuItem("复制");
private JMenuItem jmiPaste = new JMenuItem("粘贴");

public MyNotepad() {
 this.setTitle("记事本");
 this.setSize(600,400);
 this.setLocationRelativeTo(null);
 this.setDefaultCloseOperation(EXIT_ON_CLOSE);
 
 this.add(jmb,BorderLayout.NORTH);
 
 jmb.add(jmFile);
 jmb.add(jmEdit);
 jmb.add(jmFormat);
 jmb.add(jmFind);
 jmb.add(jmHelp);
 
 jmFile.add(jmiNew);
 jmFile.add(jmiOpen);
 jmFile.add(jmiSave);
 jmFile.add(jmiOther);
 jmFile.addSeparator();
 jmFile.add(jmiExit);
 
 jmFormat.add(jmiAutoLine);
 jmFormat.add(jmiFont);
 
 //上下文菜单
 jpm.add(jmiCopy);
 jpm.add(jmiPaste);
 jpm.add(jmFile);
 jta.addMouseListener(new MouseAdapter() {
 public void mouseClicked(MouseEvent e) {
  if(e.getButton() == 3){
  jpm.show(jta, e.getX(), e.getY());
  }
 }
 });
 
 //文本域自动换行
 this.add(jsp,BorderLayout.CENTER);
 
 jmiAutoLine.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e) {
  boolean selected = jmiAutoLine.isSelected();
  if(selected){
  jta.setLineWrap(true);
  }else{
  jta.setLineWrap(false);
  }
 }
 });

// 文件新建窗口
 jmiNew.addActionListener(new ActionListener() {
  public void actionPerformed(ActionEvent e) {
  int choose = jfc.showOpenDialog(MyNotepad.this);
  switch (choose) {
  case JFileChooser.APPROVE_OPTION:
   System.out.println("点击了打开");
   break;
  case JFileChooser.CANCEL_OPTION:
   System.out.println("点击了取消");
   break;
  }
  }
 });

 //文件保存窗口，用随机数命名文件名随时保存进新的文件
    jmiSave.addActionListener(new ActionListener() {
  
  @Override
  public void actionPerformed(ActionEvent arg0) {
  Random r = new Random();
  int a = r.nextInt(100);
  File file = new File("D:\\桌面\\b"+"r"+"a.txt");
  try {
   FileOutputStream fis = new FileOutputStream(file,true);
   BufferedOutputStream bis = new BufferedOutputStream(fis);
   byte [] b = jta.getText().getBytes();
   try {
   bis.write(b);
   bis.flush();
   bis.close();
   } catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
   }
   
  } catch (FileNotFoundException e) {
   e.printStackTrace();
  }
  
  }
 });
 
 jmiExit.registerKeyboardAction(new ActionListener() {
  public void actionPerformed(ActionEvent e) {
  System.exit(0);
  }
 }, KeyStroke.getKeyStroke(KeyEvent.VK_X,KeyEvent.ALT_DOWN_MASK), 
  JComponent.WHEN_IN_FOCUSED_WINDOW);//1.设置监听事件。2.设置热键alt+x关闭窗口3.设置触发当鼠标聚焦在窗口时
 
 jmiExit.addActionListener(new ActionListener() {
  public void actionPerformed(ActionEvent e) {
  System.exit(0);
  }
 });
 
 this.setVisible(true);
 }
 
 public static void main(String[] args) {
 new MyNotepad();
 }
}