Set Mnemonic key for a JButton in Java

import java.awt.FlowLayout;
import java.awt.event.KeyEvent;
//from   w  w  w. ja  va2  s .co m
import javax.swing.JButton;
import javax.swing.JFrame;

public class Main {

  public static void main(String args[]) {
    JButton jbtnA = new JButton("Alpha");

    JFrame jfrm = new JFrame();
    jfrm.setLayout(new FlowLayout());
    jfrm.setSize(300, 300);

    jbtnA.setMnemonic(KeyEvent.VK_A);

    jfrm.add(jbtnA);
    jfrm.setVisible(true);
  }
}