这是paulsamsotha的答案的一个版本，修复了一些bug，正则表达式作为参数传递，以便更通用地使用。最初允许在输入的开头插入或替换无效字符，或删除导致字段无效的前导字符（它没有实现） remove() . 一旦出现无效字符，输入就会被锁定。
这个版本应该解决所有这些问题。
示例用法：

// Store the labels and textfields for later retrieval
  Vector<JLabel> jLabels = new Vector<JLabel>(8);
  Vector<JTextField> jTextFields = new Vector<JTextField>(8);

  //Create and populate the panel.
  Container contentPane = getContentPane();

  // Wrap everything in a BorderLayout
  JPanel borderPanel = new JPanel(new BorderLayout());
  contentPane.add(borderPanel);

  // Put the input fields in the CENTER position
  JPanel fieldPanel = new JPanel(new SpringLayout());
  borderPanel.add(fieldPanel, BorderLayout.CENTER);

  // Put the input fields in the CENTER position
  JPanel fieldPanel = new JPanel(new SpringLayout());
  borderPanel.add(fieldPanel, BorderLayout.CENTER);

  String[] labels = {"Player Name: ", "Initial Chips: "};
  String[] filters = {"^[A-Za-z][A-Za-z0-9_ ]*$", "^[1-9][0-9]*$"};
  final int numPairs = labels.length;

  // Create and associate the field inputs and labels and regex filters
  for (int i = 0; i < numPairs; i++) {
     JLabel label = new JLabel(labels[i], JLabel.TRAILING);
     fieldPanel.add(label);
     JTextField textField = createFilteredField(filters[i]);
     label.setLabelFor(textField);
     fieldPanel.add(textField);
     jLabels.add(label);
     jTextFields.add(textField);
  }

代码：

/* Filtered Text Field
 * @param   regex
 *          the regular expression to which this string is to be matched
 *
 * @return  {@code true} if, and only if, this string matches the
 *          given regular expression
 *
 * @throws  PatternSyntaxException
 *          if the regular expression's syntax is invalid
 */
public JTextField createFilteredField(String regex) {
   JTextField field = new JTextField(12);
   AbstractDocument document = (AbstractDocument) field.getDocument();
   final int maxCharacters = 20;
   document.setDocumentFilter(new DocumentFilter() {

      /**
       * Invoked prior to removal of the specified region in the
       * specified Document. Subclasses that want to conditionally allow
       * removal should override this and only call supers implementation as
       * necessary, or call directly into the <code>FilterBypass</code> as
       * necessary.
       *
       * @param fb FilterBypass that can be used to mutate Document
       * @param offset the offset from the beginning &gt;= 0
       * @param length the number of characters to remove &gt;= 0
       * @exception BadLocationException  some portion of the removal range
       *   was not a valid part of the document.  The location in the exception
       *   is the first bad position encountered.
       */
      public void remove(FilterBypass fb, int offset, int length) throws
            BadLocationException {
         String text = fb.getDocument().getText(0, fb.getDocument().getLength());
         String newText = text.substring(0, offset) + text.substring(offset + length);
         if (newText.matches(regex) || newText.length() == 0) {
            super.remove(fb, offset, length);
         }
      }

      /**
       * Invoked prior to replacing a region of text in the
       * specified Document. Subclasses that want to conditionally allow
       * replace should override this and only call supers implementation as
       * necessary, or call directly into the FilterBypass.
       *
       * @param fb FilterBypass that can be used to mutate Document
       * @param offset Location in Document
       * @param length Length of text to delete
       * @param _text Text to insert, null indicates no text to insert
       * @param attrs AttributeSet indicating attributes of inserted text,
       *              null is legal.
       * @exception BadLocationException  the given insert position is not a
       *   valid position within the document
       */
      public void replace(FilterBypass fb, int offset, int length,
                          String _text, AttributeSet attrs) throws BadLocationException {

         String text = fb.getDocument().getText(0, fb.getDocument().getLength());
         String newText = text.substring(0, offset) + _text + text.substring(offset + length);
         if (newText.length() <= maxCharacters && newText.matches(regex)) {
            super.replace(fb, offset, length, _text, attrs);
         } else {
            Toolkit.getDefaultToolkit().beep();
         }
      }

      /**
       * Invoked prior to insertion of text into the
       * specified Document. Subclasses that want to conditionally allow
       * insertion should override this and only call supers implementation as
       * necessary, or call directly into the FilterBypass.
       *
       * @param fb FilterBypass that can be used to mutate Document
       * @param offset  the offset into the document to insert the content &gt;= 0.
       *    All positions that track change at or after the given location
       *    will move.
       * @param string the string to insert
       * @param attr      the attributes to associate with the inserted
       *   content.  This may be null if there are no attributes.
       * @exception BadLocationException  the given insert position is not a
       *   valid position within the document
       */
      public void insertString(FilterBypass fb, int offset, String string,
                               AttributeSet attr) throws BadLocationException {

         String text = fb.getDocument().getText(0, fb.getDocument().getLength());
         String newText = text.substring(0, offset) + string + text.substring(offset);
         if ((fb.getDocument().getLength() + string.length()) <= maxCharacters
               && newText.matches(regex)) {
            super.insertString(fb, offset, string, attr);
         } else {
            Toolkit.getDefaultToolkit().beep();
         }
      }
   });
   return field;
}

你让过滤变得更复杂了。对于插入（如果代码相同，则为replace），您可能由于 \\. 检查。您只能粘贴一个句点，因为这是您要检查的内容。至于删除，以下建议将适用。
为了简化操作，您应该只获取文档的整个文本，然后使用regex检查整个文档字符串是否与regex匹配。这比你想做的要简单得多。你可以在这里得到一个很好的过滤过程的解释。
下面是一个示例，只使用insertstring和replace。对于remove，没有什么不同，只要获取文本，并检查它是否匹配regex。我从上面链接中的答案中选取了部分示例。场景是op需要max个字符，并且只允许一个小数位。这就是正则表达式所匹配的。但也可以匹配任何您正在键入或插入的内容，例如 00 00. 00.0 ```
import java.awt.GridBagLayout;
import java.awt.Toolkit;

import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.text.AbstractDocument;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.DocumentFilter;

public class FilterDemo {

public FilterDemo() {
    JFrame frame = new JFrame();
    frame.setLayout(new GridBagLayout());
    frame.setSize(300, 300);
    frame.add(createFilteredField());
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setLocationByPlatform(true);
    frame.setVisible(true);

}

public JTextField createFilteredField() {
    JTextField field = new JTextField();
    AbstractDocument document = (AbstractDocument) field.getDocument();
    final int maxCharacters = 10;
    document.setDocumentFilter(new DocumentFilter() {
        public void replace(FilterBypass fb, int offs, int length,
                String str, AttributeSet a) throws BadLocationException {

            String text = fb.getDocument().getText(0,
                    fb.getDocument().getLength());
            text += str;
            if ((fb.getDocument().getLength() + str.length() - length) <= maxCharacters
                    && text.matches("^[0-9]+[.]?[0-9]{0,1}$")) {
                super.replace(fb, offs, length, str, a);
            } else {
                Toolkit.getDefaultToolkit().beep();
            }
        }

        public void insertString(FilterBypass fb, int offs, String str,
                AttributeSet a) throws BadLocationException {

            String text = fb.getDocument().getText(0,
                    fb.getDocument().getLength());
            text += str;
            if ((fb.getDocument().getLength() + str.length()) <= maxCharacters
                    && text.matches("^[0-9]+[.]?[0-9]{0,1}$")) {
                super.insertString(fb, offs, str, a);
            } else {
                Toolkit.getDefaultToolkit().beep();
            }
        }
    });
    return field;
}

public static void main(String[] args) {
    SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            new FilterDemo();
        }
    });
}

}