Main.java Source code

Introduction

Here is the source code for Main.java

Source

import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.HeadlessException;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;

public class Main extends JFrame {
    public Main() throws HeadlessException {
        setSize(200, 200);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLayout(new FlowLayout(FlowLayout.LEFT));

        JLabel usernameLabel = new JLabel("Username: ");
        JTextField usernameTextField = new JTextField();
        usernameTextField.setPreferredSize(new Dimension(100, 20));
        add(usernameLabel);
        add(usernameTextField);

        usernameTextField.addKeyListener(new KeyAdapter() {
            public void keyReleased(KeyEvent e) {
                JTextField textField = (JTextField) e.getSource();
                String text = textField.getText();
                textField.setText(text.toUpperCase());
            }

            public void keyTyped(KeyEvent e) {
            }

            public void keyPressed(KeyEvent e) {
            }
        });
    }

    public static void main(String[] args) {
        new Main().setVisible(true);
    }
}