java 设置密文显示框

package test;

import java.awt.Container;
import java.awt.Font;
import java.awt.GridLayout;
import java.io.File;
import java.util.EmptyStackException;
import java.util.Iterator;
import java.util.Stack;

import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JScrollPane;
import javax.swing.JSpinner;
import javax.swing.JSplitPane;
import javax.swing.JTabbedPane;
import javax.swing.JTextField;
import javax.swing.JToggleButton;

public class ImplementsDemo {
    public static void main(String[] args) throws EmptyStackException{
        JFrame f=new JFrame("Welcome To Earth!");
        JPasswordField ps1=new JPasswordField();
        JPasswordField ps2=new JPasswordField();
        ps2.setEchoChar('#');
        JLabel lab1=new JLabel("默认的回显:");
        JLabel lab2=new JLabel("回显设置@:");
        lab1.setBounds(10, 10, 100, 20);
        lab2.setBounds(10, 40, 100, 20);
        ps1.setBounds(110, 10, 80, 20);
        ps2.setBounds(110, 40, 50, 20);
        f.setLayout(null);
        f.add(lab2);
        f.add(ps1);
        f.add(lab1);
        f.add(ps2);
        f.setSize(300,100);
        f.setLocation(300,200);
        f.setVisible(true);
        
    }
    
}