1 <?php

     2 /*

     3  *  $Id$

     4  *

     5  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

     6  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

     7  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

     8  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

     9  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

    10  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

    11  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

    12  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

    13  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

    14  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

    15  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    16  *

    17  * This software consists of voluntary contributions made by many individuals

    18  * and is licensed under the LGPL. For more information, see

    19  * <http://www.doctrine-project.org>.

    20  */

    21 

    22 namespace Doctrine\Common;

    23 

    24 use Doctrine\Common\Events\Event;

    25 

    26 /**

    27  * The EventManager is the central point of Doctrine's event listener system.

    28  * Listeners are registered on the manager and events are dispatched through the

    29  * manager.

    30  * 

    31  * @license http://www.opensource.org/licenses/lgpl-license.php LGPL

    32  * @link    www.doctrine-project.org

    33  * @since   2.0

    34  * @version $Revision: 3938 $

    35  * @author  Guilherme Blanco <guilhermeblanco@hotmail.com>

    36  * @author  Jonathan Wage <jonwage@gmail.com>

    37  * @author  Roman Borschel <roman@code-factory.org>

    38  */

    39 class EventManager

    40 {

    41     /**

    42      * Map of registered listeners.

    43      * <event> => <listeners> 

    44      *

    45      * @var array

    46      */

    47     private $_listeners = array();

    48 

    49     /**

    50      * Dispatches an event to all registered listeners.

    51      *

    52      * @param string $eventName The name of the event to dispatch. The name of the event is

    53      *                          the name of the method that is invoked on listeners.

    54      * @param EventArgs $eventArgs The event arguments to pass to the event handlers/listeners.

    55      *                             If not supplied, the single empty EventArgs instance is used.

    56      * @return boolean

    57      */

    58     public function dispatchEvent($eventName, EventArgs $eventArgs = null)

    59     {

    60         if (isset($this->_listeners[$eventName])) {

    61             $eventArgs = $eventArgs === null ? EventArgs::getEmptyInstance() : $eventArgs;

    62             

    63             foreach ($this->_listeners[$eventName] as $listener) {

    64                 $listener->$eventName($eventArgs);

    65             }

    66         }

    67     }

    68 

    69     /**

    70      * Gets the listeners of a specific event or all listeners.

    71      *

    72      * @param string $event The name of the event.

    73      * @return array The event listeners for the specified event, or all event listeners.

    74      */

    75     public function getListeners($event = null)

    76     {

    77         return $event ? $this->_listeners[$event] : $this->_listeners;

    78     }

    79 

    80     /**

    81      * Checks whether an event has any registered listeners.

    82      *

    83      * @param string $event

    84      * @return boolean TRUE if the specified event has any listeners, FALSE otherwise.

    85      */

    86     public function hasListeners($event)

    87     {

    88         return isset($this->_listeners[$event]) && $this->_listeners[$event];

    89     }

    90 

    91     /**

    92      * Adds an event listener that listens on the specified events.

    93      *

    94      * @param string|array $events The event(s) to listen on.

    95      * @param object $listener The listener object.

    96      */

    97     public function addEventListener($events, $listener)

    98     {

    99         // Picks the hash code related to that listener

   100         $hash = spl_object_hash($listener);

   101         

   102         foreach ((array) $events as $event) {

   103             // Overrides listener if a previous one was associated already

   104             // Prevents duplicate listeners on same event (same instance only)

   105             $this->_listeners[$event][$hash] = $listener;

   106         }

   107     }

   108     

   109     /**

   110      * Removes an event listener from the specified events.

   111      *

   112      * @param string|array $events

   113      * @param object $listener

   114      */

   115     public function removeEventListener($events, $listener)

   116     {

   117         // Picks the hash code related to that listener

   118         $hash = spl_object_hash($listener);

   119         

   120         foreach ((array) $events as $event) {

   121             // Check if actually have this listener associated

   122             if (isset($this->_listeners[$event][$hash])) {

   123                 unset($this->_listeners[$event][$hash]);

   124             }

   125         }

   126     }

   127     

   128     /**

   129      * Adds an EventSubscriber. The subscriber is asked for all the events he is

   130      * interested in and added as a listener for these events.

   131      * 

   132      * @param Doctrine\Common\EventSubscriber $subscriber The subscriber.

   133      */

   134     public function addEventSubscriber(EventSubscriber $subscriber)

   135     {

   136         $this->addEventListener($subscriber->getSubscribedEvents(), $subscriber);

   137     }

   138 }