radar-wp/vendor/doctrine/common/lib/Doctrine/Common/EventArgs.php
2015-02-24 16:25:12 +01:00

67 lines
2.5 KiB
PHP

<?php
/*
* $Id$
*
* 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}.
*
* @license http://www.opensource.org/licenses/lgpl-license.php LGPL
* @link www.doctrine-project.org
* @since 2.0
* @version $Revision: 3938 $
* @author Guilherme Blanco <guilhermeblanco@hotmail.com>
* @author Jonathan Wage <jonwage@gmail.com>
* @author Roman Borschel <roman@code-factory.org>
*/
class EventArgs
{
/**
* @var EventArgs Single instance of 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;
}
}