import javax.swing.JFrame;
import javax.swing.Action;
import javax.swing.AbstractAction;
import javax.swing.ImageIcon;
import java.awt.event.ActionEvent;
import javax.swing.JButton;

class Program01 extends JFrame {
	Action leftAction = new LeftAction("Felirat");
	JButton btnTest = new JButton(leftAction);
	Program01() {
		add(btnTest);
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setSize(400, 300);
		centerWindow(this);
		setVisible(true);
	}
	public static void centerWindow(java.awt.Window frame) {
		java.awt.Dimension dimension =
		    java.awt.Toolkit.getDefaultToolkit().getScreenSize();
		int x = (int)((dimension.getWidth() - frame.getWidth()) / 2);
		int y = (int)((dimension.getHeight() - frame.getHeight()) / 2);
		frame.setLocation(x, y);
	}
	public static void main(String[]args) {
		new Program01();
	}

	class LeftAction extends AbstractAction {
		public LeftAction(String text) {
			super(text);
		}
		public void actionPerformed(ActionEvent e) {			
			setTitle("vmi");
		}
	}	
}