JLabel is a component used for displaying a label for some components. It is commonly partnered with a text field or a password field. JTextField is an input component allowing users to add some text. JPasswordField in Java is a special type of text field that allows you to hide or change the character being displayed to the user.
package com.javapointers.javase; import java.awt.Dimension; import java.awt.GridBagConstraints; import java.awt.GridBagLayout; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPasswordField; import javax.swing.JTextField; public class TextFieldTest { JTextField tfUsername; JPasswordField pfPassword; JLabel lblUsername, lblPassword; GridBagLayout gbl; GridBagConstraints gbc; public TextFieldTest() { tfUsername = new JTextField(20); pfPassword = new JPasswordField(20); lblUsername = new JLabel("Username"); lblPassword = new JLabel("Password"); gbl = new GridBagLayout(); gbc = new GridBagConstraints(); JFrame frame = new JFrame(); frame.setLayout(gbl); gbc.gridx = 0; gbc.gridy = 0; gbc.gridwidth = 1; gbc.gridheight = 1; frame.add(lblUsername, gbc); gbc.gridx = 1; gbc.gridwidth = 5; gbc.weightx=1; frame.add(tfUsername, gbc); gbc.gridy = 1; gbc.gridx = 0; gbc.gridwidth = 1; frame.add(lblPassword, gbc); gbc.gridx = 1; gbc.gridwidth = 5; frame.add(pfPassword, gbc); frame.pack(); frame.setVisible(true); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } public static void main(String args[]) { TextFieldTest test = new TextFieldTest(); } }
when we run our program, the UI will be:
tfUsername = new JTextField(20);
means to create a new instance of JTextField with an initial width of 20.
pfPassword = new JPasswordField(20);
create a new instants of JPasswordField with an initial width of 20.
lblUsername = new JLabel("Username");
create a new instance of JLabel that will display the string “Username”.
lblPassword = new JLabel("Password");
create a new instance of JLabel that will display the string “Password”.
The next tutorial is about how to use JTextArea in Java.