EventArgs.php in Plug 7

Namespace

Doctrine\Common

File

lib/doctrine/common/lib/Doctrine/Common/EventArgs.php

<?php

/*
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the MIT license. For more information, see
 * <http://www.doctrine-project.org>.
 */
namespace Doctrine\Common;


/**
 * EventArgs is the base class for classes containing event data.
 *
 * This class contains no event data. It is used by events that do not pass state
 * information to an event handler when an event is raised. The single empty EventArgs
 * instance can be obtained through {@link getEmptyInstance}.
 *
 * @link   www.doctrine-project.org
 * @since  2.0
 * @author Guilherme Blanco <[e-mail]>
 * @author Jonathan Wage <[e-mail]>
 * @author Roman Borschel <[e-mail]>
 */
class EventArgs {

  /**
   * Single instance of EventArgs.
   *
   * @var EventArgs
   */
  private static $_emptyEventArgsInstance;

  /**
   * Gets the single, empty and immutable EventArgs instance.
   *
   * This instance will be used when events are dispatched without any parameter,
   * like this: EventManager::dispatchEvent('eventname');
   *
   * The benefit from this is that only one empty instance is instantiated and shared
   * (otherwise there would be instances for every dispatched in the abovementioned form).
   *
   * @see EventManager::dispatchEvent
   *
   * @link http://msdn.microsoft.com/en-us/library/system.eventargs.aspx
   *
   * @return EventArgs
   */
  public static function getEmptyInstance() {
    if (!self::$_emptyEventArgsInstance) {
      self::$_emptyEventArgsInstance = new EventArgs();
    }
    return self::$_emptyEventArgsInstance;
  }

}

Classes

Name	Description
EventArgs	EventArgs is the base class for classes containing event data.