public void init() {
    // 添加按钮
    JPanel buttonPanel = new JPanel();
    buttonPanel.add(okButton);

    mainPanel.setLayout(new GridLayout(0, 3));
    mainWin.add(mainPanel, BorderLayout.CENTER);

    JFormattedTextField intField0 =
        new JFormattedTextField(
            new InternationalFormatter(NumberFormat.getIntegerInstance()) {
              protected DocumentFilter getDocumentFilter() {
                return new NumberFilter();
              }
            });
    intField0.setValue(100);
    addRow("只接受数字的文本框", intField0);

    JFormattedTextField intField1 = new JFormattedTextField(NumberFormat.getIntegerInstance());
    intField1.setValue(new Integer(100));
    // 添加输入校验器
    intField1.setInputVerifier(new FormattedTextFieldVerifier());
    addRow("带输入校验器的文本框", intField1);

    // 创建自定义格式器对象
    IPAddressFormatter ipFormatter = new IPAddressFormatter();
    ipFormatter.setOverwriteMode(false);
    // 以自定义格式器对象创建格式化文本框
    JFormattedTextField ipField = new JFormattedTextField(ipFormatter);
    ipField.setValue(new byte[] {(byte) 192, (byte) 168, 4, 1});
    addRow("IP地址格式", ipField);

    mainWin.add(buttonPanel, BorderLayout.SOUTH);
    mainWin.pack();
    mainWin.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    mainWin.setVisible(true);
  }
  public FormatTestFrame() {
    JPanel buttonPanel = new JPanel();
    okButton = new JButton("Ok");
    buttonPanel.add(okButton);
    add(buttonPanel, BorderLayout.SOUTH);

    mainPanel = new JPanel();
    mainPanel.setLayout(new GridLayout(0, 3));
    add(mainPanel, BorderLayout.CENTER);

    JFormattedTextField intField = new JFormattedTextField(NumberFormat.getIntegerInstance());
    intField.setValue(new Integer(100));
    addRow("Number:", intField);

    JFormattedTextField intField2 = new JFormattedTextField(NumberFormat.getIntegerInstance());
    intField2.setValue(new Integer(100));
    intField2.setFocusLostBehavior(JFormattedTextField.COMMIT);
    addRow("Number (Commit behavior):", intField2);

    JFormattedTextField intField3 =
        new JFormattedTextField(
            new InternationalFormatter(NumberFormat.getIntegerInstance()) {
              protected DocumentFilter getDocumentFilter() {
                return filter;
              }
            });
    intField3.setValue(new Integer(100));
    addRow("Filtered Number", intField3);

    JFormattedTextField intField4 = new JFormattedTextField(NumberFormat.getIntegerInstance());
    intField4.setValue(new Integer(100));
    intField4.setInputVerifier(
        new InputVerifier() {
          public boolean verify(JComponent component) {
            JFormattedTextField field = (JFormattedTextField) component;
            return field.isEditValid();
          }
        });
    addRow("Verified Number:", intField4);

    JFormattedTextField currencyField = new JFormattedTextField(NumberFormat.getCurrencyInstance());
    currencyField.setValue(new Double(10));
    addRow("Currency:", currencyField);

    JFormattedTextField dateField = new JFormattedTextField(DateFormat.getDateInstance());
    dateField.setValue(new Date());
    addRow("Date (default):", dateField);

    DateFormat format = DateFormat.getDateInstance(DateFormat.SHORT);
    format.setLenient(false);
    JFormattedTextField dateField2 = new JFormattedTextField(format);
    dateField2.setValue(new Date());
    addRow("Date (short, not lenient):", dateField2);

    try {
      DefaultFormatter formatter = new DefaultFormatter();
      formatter.setOverwriteMode(false);
      JFormattedTextField urlField = new JFormattedTextField(formatter);
      urlField.setValue(new URL("http://java.sun.com"));
      addRow("URL:", urlField);
    } catch (MalformedURLException ex) {
      ex.printStackTrace();
    }

    try {
      MaskFormatter formatter = new MaskFormatter("###-##-####");
      formatter.setPlaceholderCharacter('0');
      JFormattedTextField ssnField = new JFormattedTextField(formatter);
      ssnField.setValue("078-05-1120");
      addRow("SSN Mask:", ssnField);
    } catch (ParseException ex) {
      ex.printStackTrace();
    }

    JFormattedTextField ipField = new JFormattedTextField(new IPAddressFormatter());
    ipField.setValue(new byte[] {(byte) 130, 65, 86, 66});
    addRow("IP Address:", ipField);
    pack();
  }
 // 当输入组件失去焦点时,该方法被触发
 public boolean verify(JComponent component) {
   JFormattedTextField field = (JFormattedTextField) component;
   // 返回用户输入是否有效
   return field.isEditValid();
 }