@@ -27,7 +27,7 @@ import org.openqa.selenium.internal.Locatable;
  */
 public abstract class SingleKeyAction extends KeysRelatedAction {
   protected final Keys key;
-  private static final Keys[] MODIFIER_KEYS = {Keys.SHIFT, Keys.CONTROL, Keys.ALT};
+  private static final Keys[] MODIFIER_KEYS = {Keys.SHIFT, Keys.CONTROL, Keys.ALT, Keys.META, Keys.COMMAND, Keys.LEFT_ALT, Keys.LEFT_CONTROL, Keys.LEFT_SHIFT};
 
   protected SingleKeyAction(Keyboard keyboard, Mouse mouse, Keys key) {
     this(keyboard, mouse, null, key);
/*
Copyright 2007-2010 Selenium committers

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
 */

package org.openqa.selenium.interactions.internal;

import org.openqa.selenium.Keys;
import org.openqa.selenium.interactions.Keyboard;
import org.openqa.selenium.interactions.Mouse;
import org.openqa.selenium.internal.Locatable;

/**
 * Used both by KeyDownAction and KeyUpAction
 * 
 */
public abstract class SingleKeyAction extends KeysRelatedAction {
  protected final Keys key;
  private static final Keys[] MODIFIER_KEYS = {Keys.SHIFT, Keys.CONTROL, Keys.ALT};

  protected SingleKeyAction(Keyboard keyboard, Mouse mouse, Keys key) {
    this(keyboard, mouse, null, key);
  }

  protected SingleKeyAction(Keyboard keyboard, Mouse mouse, Locatable locationProvider, Keys key) {
    super(keyboard, mouse, locationProvider);
    this.key = key;
    boolean isModifier = false;
    for (Keys modifier : MODIFIER_KEYS) {
      isModifier = isModifier | modifier.equals(key);
    }

    if (!isModifier) {
      throw new IllegalArgumentException("Key Down / Up events only make sense for modifier keys.");
    }

  }
}

LEFT_ALT, LEFT_CONTROL, and LEFT_SHIFT should already be aliases. META could be an alias for ALT but probably isn't yet.