Java Key Listener

Java key listener

Created By: chatGPT

Java KeyListener is an interface that receives keyboard events. To use it, one must implement the KeyListener interface, overriding its methods. This allows you to handle keyboard input from users in a GUI application. Below is an example that demonstrates how to implement a KeyListener in a Java Swing application.

import javax.swing.*;
import java.awt.event.*;

public class KeyListenerExample extends JFrame implements KeyListener {

    JTextArea textArea;

    public KeyListenerExample() {
        setTitle("KeyListener Example");
        setSize(400, 300);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        textArea = new JTextArea();
        textArea.addKeyListener(this);
        add(textArea);
        setVisible(true);
    }

    @Override
    public void keyTyped(KeyEvent e) {
        // Process key typed event
        System.out.println("Key Typed: " + e.getKeyChar());
    }

    @Override
    public void keyPressed(KeyEvent e) {
        // Process key pressed event
        System.out.println("Key Pressed: " + e.getKeyCode());
    }

    @Override
    public void keyReleased(KeyEvent e) {
        // Process key released event
        System.out.println("Key Released: " + e.getKeyCode());
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(KeyListenerExample::new);
    }
}

In the example above, the KeyListenerExample class extends JFrame and implements the KeyListener interface. The main GUI component is a JTextArea where keyboard input is captured. The keyTyped, keyPressed, and keyReleased methods are overridden to respond to the corresponding keyboard events. Whenever a key is pressed, typed, or released, a message is printed in the console indicating the action and the key involved.You can run this example in your Java development environment. When you type in the text area, you should see output in the console reflecting the key events. Remember to import the necessary classes to avoid compilation errors. This simple setup helps in understanding how to capture and respond to keyboard events in Java applications.