您可以为此使用NavigationFilter。
这是一个入门的示例：
import java.awt.event.*;import javax.swing.*;import javax.swing.text.*;public class NavigationFilterPrefixWithBackspace extends NavigationFilter{ private int prefixLength; private Action deletePrevious; public NavigationFilterPrefixWithBackspace(int prefixLength, JTextComponent component) { this.prefixLength = prefixLength; deletePrevious = component.getActionMap().get("delete-previous"); component.getActionMap().put("delete-previous", new BackspaceAction()); component.setCaretPosition(prefixLength); } public void setDot(NavigationFilter.FilterBypass fb, int dot, Position.Bias bias) { fb.setDot(Math.max(dot, prefixLength), bias); } public void moveDot(NavigationFilter.FilterBypass fb, int dot, Position.Bias bias) { fb.moveDot(Math.max(dot, prefixLength), bias); } class BackspaceAction extends AbstractAction { public void actionPerformed(ActionEvent e) { JTextComponent component = (JTextComponent)e.getSource(); if (component.getCaretPosition() > prefixLength) { deletePrevious.actionPerformed( null ); } } } public static void main(String args[]) throws Exception { JTextField textField = new JTextField("Prefix_", 20); textField.setNavigationFilter( new NavigationFilterPrefixWithBackspace(7, textField) ); Jframe frame = new Jframe("Navigation Filter Example"); frame.setDefaultCloseOperation(Jframe.EXIT_ON_CLOSE); frame.getContentPane().add(textField); frame.pack(); frame.setLocationRelativeTo( null ); frame.setVisible(true); }}I believe this is a how a JFormattedTextField works. So I’m not sure if you
can use this with a formatted text field as is may replace the default
behaviour.
