import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JTextField;

public class Program01 extends JFrame {
	JButton varGomb = new JButton("Vár");
	JButton valtGomb = new JButton("Vált");
	JTextField mezo = new JTextField(4);

	public Program01() {
		varGomb.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				varGombActionListener(arg0);
			}
		});
		valtGomb.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				mezo.setText("Valami");
			}
		});

		this.setDefaultCloseOperation(EXIT_ON_CLOSE);
		this.setLayout(new FlowLayout());
		this.add(varGomb);
		this.add(valtGomb);
		this.add(mezo);
		this.pack();
		this.setVisible(true);
	}

	private void varGombActionListener(ActionEvent e) {
		(new Thread() {
			public void run() {
				try {
					Thread.sleep(5000);
					setWindowTitle();
				} catch (InterruptedException e) {
					System.err.println("Megszakítási hiba!");
				}
			}
		}).start();
	}

	private void setWindowTitle() {
		this.setTitle("Működik");
	}

	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				new Program01();
			}
		});
	}
}