Java JPasswordField

The object of a JPasswordField class is a text component specialized for password entry. It allows the editing of a single line of text. It inherits JTextField class.

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JPasswordField class declaration

Let's see the declaration for javax.swing.JPasswordField class.

1. public class JPasswordField extends JTextField  

Commonly used Constructors:

Constructor	Description
JPasswordField()	Constructs a new JPasswordField, with a default document, null starting text string, and 0 column width.
JPasswordField(int columns)	Constructs a new empty JPasswordField with the specified number of columns.
JPasswordField(String text)	Constructs a new JPasswordField initialized with the specified text.
JPasswordField(String text, int columns)	Construct a new JPasswordField initialized with the specified text and columns.

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Java JPasswordField Example

1. import javax.swing.*;    
2. public class PasswordFieldExample {  
3.     public static void main(String[] args) {    
4.     JFrame f=new JFrame("Password Field Example");    
5.      JPasswordField value = new JPasswordField();   
6.      JLabel l1=new JLabel("Password:");    
7.         l1.setBounds(20,100, 80,30);    
8.          value.setBounds(100,100,100,30);    
9.             f.add(value);  f.add(l1);  
10.             f.setSize(300,300);    
11.             f.setLayout(null);    
12.             f.setVisible(true);     
13. }  
14. }  

Output:

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Java JPasswordField Example with ActionListener

1. import javax.swing.*;    
2. import java.awt.event.*;  
3. public class PasswordFieldExample {  
4.     public static void main(String[] args) {    
5.     JFrame f=new JFrame("Password Field Example");    
6.      final JLabel label = new JLabel();            
7.      label.setBounds(20,150, 200,50);  
8.      final JPasswordField value = new JPasswordField();   
9.      value.setBounds(100,75,100,30);   
10.      JLabel l1=new JLabel("Username:");    
11.         l1.setBounds(20,20, 80,30);    
12.         JLabel l2=new JLabel("Password:");    
13.         l2.setBounds(20,75, 80,30);    
14.         JButton b = new JButton("Login");  
15.         b.setBounds(100,120, 80,30);    
16.         final JTextField text = new JTextField();  
17.         text.setBounds(100,20, 100,30);    
18.                 f.add(value); f.add(l1); f.add(label); f.add(l2); f.add(b); f.add(text);  
19.                 f.setSize(300,300);    
20.                 f.setLayout(null);    
21.                 f.setVisible(true);     
22.                 b.addActionListener(new ActionListener() {  
23.                 public void actionPerformed(ActionEvent e) {       
24.                    String data = "Username " + text.getText();  
25.                    data += ", Password: "   
26.                    + new String(value.getPassword());   
27.                    label.setText(data);          
28.                 }  
29.              });   
30. }  
31. }  

Output: