Java Action MNEMONIC_KEY

static final String MNEMONIC_KEY

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
/*w  w w  .j a  va 2  s .  co  m*/
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.plaf.metal.MetalIconFactory;

public class Main {
  public static void main(String[] a) {
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    Action action = new ShowAction();
    JButton button = new JButton(action);

    frame.add(button, BorderLayout.CENTER);
    frame.setSize(350, 150);
    frame.setVisible(true);
  }
}

class ShowAction extends AbstractAction {
  public ShowAction() {
    super("About");
    putValue(Action.MNEMONIC_KEY, new Integer(KeyEvent.VK_A));
    putValue(Action.SMALL_ICON, MetalIconFactory.getFileChooserHomeFolderIcon());
  }

  public void actionPerformed(ActionEvent actionEvent) {
    System.out.println("About Swing");
  }
}