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