Java JTextField

Last Updated : 18 Sept 2026

JTextField is a Swing component in Java that allows users to input single-line text. It is essentially a blank space where users can type characters. It is commonly used in GUI (Graphical User Interface) applications to accept textual input from users. The object of a JTextField class is a text component that allows the editing of single-line text. It inherits the JTextComponent class.

JTextField Class Declaration

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

Commonly used Constructors

Constructor	Description
JTextField()	Creates a new TextField
JTextField(String text)	Creates a new TextField initialized with the specified text.
JTextField(String text, int columns)	Creates a new TextField initialized with the specified text and columns.
JTextField(int columns)	Creates a new empty TextField with the specified number of columns.

Commonly used Methods

Methods	Description
void addActionListener(ActionListener l)	It is used to add the specified action listener to receive action events from this textfield.
Action getAction()	It returns the currently set Action for this ActionEvent source, or null if no Action is set.
void setFont(Font f)	It is used to set the current font.
void removeActionListener(ActionListener l)	It is used to remove the specified action listener so that it no longer receives action events from this textfield.

Java JTextField Example

TextFieldExample.java

import javax.swing.*;
// Main class TextFieldExample
class TextFieldExample  
{  
    public static void main(String args[])  
    {  
        // Creating a JFrame object with title "TextField Example."
        JFrame f= new JFrame("TextField Example");  
        // Creating two JTextField objects
        JTextField t1, t2;  
        // Initializing the first JTextField with default text "Welcome to Javatpoint."
        t1 = new JTextField("Welcome to Javatpoint.");  
        // Setting the position and size of the first JTextField
        t1.setBounds(50,100, 200,30);  
        // Initializing the second JTextField with default text "AWT Tutorial"
        t2 = new JTextField("AWT Tutorial");  
        // Setting the position and size of the second JTextField
        t2.setBounds(50,150, 200,30);  
        // Adding JTextFields to the JFrame
        f.add(t1);
        f.add(t2);
        // Setting the size of the JFrame
        f.setSize(400,400);  
        // Setting layout to null to use absolute positioning
        f.setLayout(null);  
        // Making the JFrame visible
        f.setVisible(true);  
    }  
}  

Output:

Java JTextField Example with ActionListener

import javax.swing.*;
import java.awt.event.*;
public class TextFieldExample implements ActionListener {
    // Declaration of JTextField and JButton objects
    JTextField tf1, tf2, tf3;
    JButton b1, b2;
    // Constructor
    TextFieldExample() {
        // Creating a JFrame object
        JFrame f = new JFrame();       
        // Creating JTextField objects
        tf1 = new JTextField();
        tf1.setBounds(50, 50, 150, 20);        
        tf2 = new JTextField();
        tf2.setBounds(50, 100, 150, 20);        
        tf3 = new JTextField();
        tf3.setBounds(50, 150, 150, 20);
        // Making tf3 non-editable
        tf3.setEditable(false);
        // Creating JButton objects
        b1 = new JButton("+");
        b1.setBounds(50, 200, 50, 50);        
        b2 = new JButton("-");
        b2.setBounds(120, 200, 50, 50);
        // Adding ActionListener to buttons
        b1.addActionListener(this);
        b2.addActionListener(this);
        // Adding components to the JFrame
        f.add(tf1);
        f.add(tf2);
        f.add(tf3);
        f.add(b1);
        f.add(b2);
        // Setting JFrame size and layout
        f.setSize(300, 300);
        f.setLayout(null);
        // Making JFrame visible
        f.setVisible(true);
    }
    // actionPerformed method from ActionListener interface
    public void actionPerformed(ActionEvent e) {
        // Retrieving text from text fields
        String s1 = tf1.getText();
        String s2 = tf2.getText();       
        // Converting string inputs to integers
        int a = Integer.parseInt(s1);
        int b = Integer.parseInt(s2);        
        // Variable to hold the result
        int c = 0;        
        // Checking which button is clicked
        if (e.getSource() == b1) {
            c = a + b; // Addition
        } else if (e.getSource() == b2) {
            c = a - b; // Subtraction
        }        
        // Converting result back to a string
        String result = String.valueOf(c);        
        // Setting the result in the third text field
        tf3.setText(result);
    }
    public static void main(String[] args) {
        // Creating an instance of TextFieldExample
        new TextFieldExample();
    }
}

Output:

Example: Creating a Simple Login Form

LoginForm.java

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class LoginForm {
    public static void main(String[] args) {
        // Create the main frame
        JFrame frame = new JFrame("Login Form");        
        // Create a panel to hold components
        JPanel panel = new JPanel();        
        // Create text fields for username and password
        JTextField usernameField = new JTextField(20);
        JPasswordField passwordField = new JPasswordField(20);        
        // Create a button for login
        JButton loginButton = new JButton("Login");
        // Add components to the panel
        panel.add(new JLabel("Username: "));
        panel.add(usernameField);
        panel.add(new JLabel("Password: "));
        panel.add(passwordField);
        panel.add(loginButton);
        // Add action listener to the login button
        loginButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                // Retrieve username and password entered by the user
                String username = usernameField.getText();
                String password = new String(passwordField.getPassword());                
                // Validate username and password
                if (username.equals("admin") && password.equals("password")) {
                    // Show a success message if login is successful
                    JOptionPane.showMessageDialog(frame, "Login successful!");
                } else {
                    // Show an error message if login fails
                    JOptionPane.showMessageDialog(frame, "Invalid username or password");
                }
            }
        });
        // Add the panel to the frame
        frame.add(panel);        
        // Set frame properties
        frame.setSize(300, 150);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
}

Output:

Example: Calculating the Area of Rectangle

RectangleAreaCalculator.java

import javax.swing.*;
import java.awt.event.*;
public class RectangleAreaCalculator implements ActionListener {
    JTextField lengthField, widthField, resultField;
    JButton calculateButton;
    RectangleAreaCalculator() {
        // Create JFrame
        JFrame frame = new JFrame("Rectangle Area Calculator");
        frame.setSize(300, 200);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLayout(null);
        // Create JLabels
        JLabel lengthLabel = new JLabel("Length:");
        lengthLabel.setBounds(20, 20, 60, 20);
        JLabel widthLabel = new JLabel("Width:");
        widthLabel.setBounds(20, 50, 60, 20);
        JLabel resultLabel = new JLabel("Area:");
        resultLabel.setBounds(20, 80, 60, 20);
        // Create JTextFields
        lengthField = new JTextField();
        lengthField.setBounds(90, 20, 150, 20);
        widthField = new JTextField();
        widthField.setBounds(90, 50, 150, 20);
        resultField = new JTextField();
        resultField.setBounds(90, 80, 150, 20);
        resultField.setEditable(false);
        // Create JButton
        calculateButton = new JButton("Calculate");
        calculateButton.setBounds(90, 110, 100, 30);
        calculateButton.addActionListener(this);
        // Add components to the frame
        frame.add(lengthLabel);
        frame.add(widthLabel);
        frame.add(resultLabel);
        frame.add(lengthField);
        frame.add(widthField);
        frame.add(resultField);
        frame.add(calculateButton);
        // Make the frame visible
        frame.setVisible(true);
    }
    public void actionPerformed(ActionEvent e) {
        // Calculate area when the button is clicked
        if (e.getSource() == calculateButton) {
            try {
                // Get length and width from text fields
                double length = Double.parseDouble(lengthField.getText());
                double width = Double.parseDouble(widthField.getText());
                // Calculate area
                double area = length * width;
                // Display result in resultField
                resultField.setText(String.format("%.2f", area));
            } catch (NumberFormatException ex) {
                // Handle invalid input
                JOptionPane.showMessageDialog(null, "Please enter valid numbers for length and width.");
            }
        }
    }
    public static void main(String[] args) {
        // Create an instance of RectangleAreaCalculator
        new RectangleAreaCalculator();
    }
}

Output:

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