1  /*
     2   * Copyright the original author or authors.
     3   * 
     4   * Licensed under the MOZILLA PUBLIC LICENSE, Version 1.1 (the "License");
     5   * you may not use this file except in compliance with the License.
     6   * You may obtain a copy of the License at
     7   * 
     8   *      http://www.mozilla.org/MPL/MPL-1.1.html
     9   * 
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16   
    17  import org.as2lib.env.event.EventListenerSource;
    18  import org.as2lib.env.log.LogSupport;
    19  import org.as2lib.env.event.distributor.CompositeEventDistributorControl;
    20  import org.as2lib.env.event.distributor.SimpleConsumableCompositeEventDistributorControl;
    21  
    22  /**
    23   * {@code EventSupport} provides simple access to events.
    24   * 
    25   * <p>To apply event abilities to your class its only necessary to extend
    26   * {@code EventSupport}. It holds in the private instance variable
    27   * {@code distributorControl} a reference to
    28   * {@link SimpleConsumableCompositeEventDistributionControl}.
    29   * 
    30   * <p>To allow additional listener types to be checked by {@link #addListener},
    31   * {@link #addAddListener} its only necessary to add {@code acceptListenerType(AnyType);}
    32   * within the constructor of the extended class.
    33   * 
    34   * <p>It is necessary for sending a event to recieve the matching distributor with
    35   * {@code distributorControl.getDistributor(AnyType)} and execute the event to it.
    36   * 
    37   * <p>Example code:
    38   * <code>
    39   *   class Controller extends EventSupport {
    40   *   
    41   *     private var model:Model;
    42   *     private var distributor:View;
    43   *     
    44   *     public function Controller(Void) {
    45   *       distributorControl.acceptListenerType(View);
    46   *       distributor = distributorControl.getDistributor(View);
    47   *     }
    48   *     
    49   *     public function setTargetModel(model:Model) {
    50   *       this.model = model;
    51   *       distributor.onTargetModelChanged(this);
    52   *     }
    53   *     
    54   *     public function getTargetModel(Void):Model {
    55   *     	 return model;
    56   *     }
    57   *   }
    58   * </code>
    59   * 
    60   * @author Martin Heidegger
    61   * @version 1.0
    62   */
    63  class org.as2lib.env.event.EventSupport extends LogSupport implements EventListenerSource {
    64  	
    65  	/** Access to event control. */
    66  	private var distributorControl:CompositeEventDistributorControl;
    67  	
    68  	/**
    69  	 * Constructs a new {@code EventSupport} instance.
    70  	 */
    71  	function EventSupport(Void) {
    72  		distributorControl = new SimpleConsumableCompositeEventDistributorControl();
    73  	}
    74  
    75  	/**
    76  	 * Adds the passed-in {@code listener} to be executed by events.
    77  	 * 
    78  	 * @param listener the listener to add
    79  	 * @throws IllegalArgumentException if the listener does not match any expected type
    80  	 */
    81  	public function addListener(listener):Void {
    82  		distributorControl.addListener(listener);
    83  	}	
    84  
    85  	/**
    86  	 * Adds all listener contained in the passed-in {@code listeners} array.
    87  	 * 
    88  	 * <p>All listeners get added after each other. If one listener does not match
    89  	 * any expected type the rest of the listeners will not be added an a exception
    90  	 * will raise.
    91  	 * 
    92  	 * @param listeners the list of listeners to add
    93  	 * @throws IllegalArgumentException if any listener does not match any expected type
    94  	 */
    95  	public function addAllListeners(listeners:Array):Void {
    96  		distributorControl.addAllListeners(listeners);
    97  	}
    98  
    99  
   100  	/**
   101  	 * Removes the passed-in {@code listener} from beeing executed by events.
   102  	 * 
   103  	 * @param listener the listener to remove
   104  	 */
   105  	public function removeListener(listener):Void {
   106  		distributorControl.removeListener(listener);
   107  	}
   108  
   109  	/**
   110  	 * Removes all listeners from beeing executed by events.
   111  	 */
   112  	public function removeAllListeners(Void):Void {
   113  		distributorControl.removeAllListeners();
   114  	}
   115  
   116  	/**
   117  	 * Getter for the list of all added listeners.
   118  	 * 
   119  	 * <p>This method returns a copy (not a reference) of the list of all added
   120  	 * listeners.
   121  	 * 
   122  	 * @return list that contains all added listeners
   123  	 */
   124  	public function getAllListeners(Void):Array {
   125  		return distributorControl.getAllListeners();
   126  	}
   127  
   128  	/**
   129  	 * Checks if the passed-in {@code listener} has been added.
   130  	 * 
   131  	 * @return {@code true} if the listener has been added
   132  	 */
   133  	public function hasListener(listener):Boolean {
   134  		return distributorControl.hasListener(listener);
   135  	}
   136  	
   137  	/**
   138  	 * Internal method to accept a concrete listener type.
   139  	 * 
   140  	 * <p>Any listener added with {@code addListener} will be checked against
   141  	 * all accepted typed and added.
   142  	 * 
   143  	 * @param type to accept as listener
   144  	 */
   145  	private function acceptListenerType(type:Function):Void {
   146  		distributorControl.acceptListenerType(type);
   147  	}
   148  	
   149  }
as2api