Java Swing Tutorial - Java ActionEvent ALT_MASK

Syntax

ActionEvent.ALT_MASK has the following syntax.

public static final int ALT_MASK

Example

In the following code shows how to use ActionEvent.ALT_MASK field.

// w w  w. j a  va  2s .  co  m
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

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

class MyActionListener implements ActionListener {
  public void actionPerformed(ActionEvent e) {
    System.out.println("Command: " + e.getActionCommand());
    int modifiers = e.getModifiers();
    System.out.println("\tALT : "
        + checkMod(modifiers, ActionEvent.ALT_MASK));
    System.out.println("\tCTRL : "
        + checkMod(modifiers, ActionEvent.CTRL_MASK));
    System.out.println("\tMETA : "
        + checkMod(modifiers, ActionEvent.META_MASK));
    System.out.println("\tSHIFT: "
        + checkMod(modifiers, ActionEvent.SHIFT_MASK));
    Object source = e.getSource();
    if (source instanceof JButton) {
      JButton jb = (JButton) source;
      System.out.println("JButton: " + jb.getText());
    }
  }

  private boolean checkMod(int modifiers, int mask) {
    return ((modifiers & mask) == mask);
  }
}

public class Main {
  public static void main(String args[]) {
    JFrame frame = new JFrame();

    JButton button = new JButton("Click and holding alt, control, and shift key");
    button.addActionListener(new MyActionListener());
    frame.add(button);
    frame.pack();
    frame.setVisible(true);
  }
}