使Java的JButton文字隐藏功能的实现(不隐藏按钮的前提)

package csdn.article;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class JButtonTextSize extends JFrame {
  public static void main(String[] args) {
    new JButtonTextSize();
  }
  JButtonTextSize(){
    ImageIcon i = new ImageIcon("./images/1.jpg");
    i.setImage(i.getImage().getScaledInstance(50,50,0));//控制图片大小

    JButton jb = new JButton("测试文字");
    jb.setSize(200,100);
    jb.setLocation(0,0);//因JFrame的Layout设置了null，所以需要设置setLocation
    jb.setFont(new Font("宋体",1,20));
    jb.setIcon(i);

    JButton change = new JButton("隐藏上面按钮文字");
    change.addActionListener(new ActionListener() {
      @Override
      public void actionPerformed(ActionEvent e) {
        jb.setFont(new Font("宋体",1,0));
        repaint();
      }
    });
    change.setSize(200,100);
    change.setLocation(0,100);

    add(jb);
    add(change);
    setLayout(null);
    setVisible(true);
    setResizable(false);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setSize(500,500);
    setLocation(500,500);
  }
}