Java JPasswordField

1 Java JPasswordField的介绍

JPasswordField类的对象是专用于输入密码的文本组件。它允许编辑一行文本。它继承了JTextField类。

2 Java JPasswordField的声明

我们来看一下javax.swing.JPasswordField类的声明。

public class JPasswordField extends JTextField  

3 Java JPasswordField的构造方法

4 Java JPasswordField的案例1

package com.yiidian;

/**
 * 一点教程网： http://www.yiidian.com
 */

import javax.swing.*;

public class PasswordFieldExample {  
    public static void main(String[] args) {    
    JFrame f=new JFrame("JPasswordField案例");
     JPasswordField value = new JPasswordField();   
     JLabel l1=new JLabel("密码:");
        l1.setBounds(20,100, 80,30);    
         value.setBounds(100,100,100,30);    
            f.add(value);  f.add(l1);  
            f.setSize(300,300);    
            f.setLayout(null);    
            f.setVisible(true);     
}  
}  

输出结果为：

5 Java JPasswordField的案例2

package com.yiidian;

/**
 * 一点教程网： http://www.yiidian.com
 */

import javax.swing.*;
import java.awt.event.*;
public class PasswordFieldExample {
    public static void main(String[] args) {
        JFrame f=new JFrame("JPasswordField案例");
        final JLabel label = new JLabel();
        label.setBounds(20,150, 200,50);
        final JPasswordField value = new JPasswordField();
        value.setBounds(100,75,100,30);
        JLabel l1=new JLabel("Username:");
        l1.setBounds(20,20, 80,30);
        JLabel l2=new JLabel("Password:");
        l2.setBounds(20,75, 80,30);
        JButton b = new JButton("Login");
        b.setBounds(100,120, 80,30);
        final JTextField text = new JTextField();
        text.setBounds(100,20, 100,30);
        f.add(value); f.add(l1); f.add(label); f.add(l2); f.add(b); f.add(text);
        f.setSize(300,300);
        f.setLayout(null);
        f.setVisible(true);
        b.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                String data = "Username " + text.getText();
                data += ", Password: "
                        + new String(value.getPassword());
                label.setText(data);
            }
        });
    }
}  

输出结果为：