Handling Key Board Events

Java program that demonstrates the use of KeyAdapter and handles key events. In this example, we’ll create a basic frame and override the keyPressed() method from KeyAdapter to respond to key presses.

import java.awt.*;
import java.awt.event.*;

public class KeyAdapterExample {
    public static void main(String[] args) {
        Frame frame = new Frame("KeyAdapter Example");
        frame.setSize(400, 400);
        frame.setLayout(null);

        Label label = new Label("Press a key...");
        label.setBounds(150, 180, 100, 20);
        frame.add(label);

        // Add a KeyListener using KeyAdapter
        frame.addKeyListener(new KeyAdapter() {
            @Override
            public void keyPressed(KeyEvent e) {
                // Handle key press events
                int keyCode = e.getKeyCode();
                label.setText("Key code: " + keyCode);
            }
        });

        // Add a WindowListener to close the program
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0); // Exit the program
            }
        });

        frame.setVisible(true);
    }
}

In this program:
We create a Frame named “KeyAdapter Example.”
We add a KeyAdapter to the frame using frame.addKeyListener(...).
The overridden keyPressed() method prints the key that was pressed.
We create a Label named “Press a key…” to display the key code.
The keyPressed() method updates the label text with the key code.We add a WindowListener using frame.addWindowListener(...).
The overridden windowClosing() method calls System.exit(0) to close the program when the window is closed.

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