/*

  * Copyright 2004-2008 the Seasar Foundation and the Others.

  *

  * Licensed under the Apache License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  *

  *     http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, 

  * either express or implied. See the License for the specific language

  * governing permissions and limitations under the License.

  */

 package org.seasar.uruma.rcp.binding;

 import java.util.ArrayList;

 import java.util.List;

 import org.eclipse.core.commands.AbstractHandler;

 import org.eclipse.core.commands.ExecutionEvent;

 import org.eclipse.core.commands.ExecutionException;

 import org.eclipse.core.commands.HandlerEvent;

 import org.eclipse.core.commands.IHandler;

 import org.eclipse.swt.widgets.Event;

 import org.eclipse.swt.widgets.Listener;

 import org.seasar.uruma.log.UrumaLogger;

 import org.seasar.uruma.util.AssertionUtil;

 /**

  * 任意のメソッドを呼び出すことができる、汎用的な {@link IHandler} の実装クラスです。<br />

  * 

  * @author y-komori

  */

 public class GenericHandler extends AbstractHandler {

     protected static final UrumaLogger logger = UrumaLogger

             .getLogger(GenericHandler.class);

     protected List<Listener> listeners = new ArrayList<Listener>();

     protected boolean enabled = true;

     /*

      * @see org.eclipse.core.commands.AbstractHandler#execute(org.eclipse.core.commands.ExecutionEvent)

      */

     @Override

     public Object execute(final ExecutionEvent event) throws ExecutionException {

         int size = listeners.size();

         for (int i = 0; i < size; i++) {

             try {

                 listeners.get(i).handleEvent((Event) event.getTrigger());

             } catch (Throwable ex) {

                 logger.log(ex);

             }

         }

         return null;

     }

     /**

      * {@link Listener} を追加します。<br />

      * 

      * @param listener

      *            {@link Listener} オブジェクト

      */

     public void addListener(final Listener listener) {

         AssertionUtil.assertNotNull("listener", listener);

         this.listeners.add(listener);

     }

     /*

      * @see org.eclipse.core.commands.AbstractHandler#isEnabled()

      */

     @Override

     public boolean isEnabled() {

         return enabled;

     }

     /**

      * ハンドラのイネーブル状態を変更します。<br />

      * 

      * @param enabled

      *            <code>true</code> の場合、イネーブル。<code>false</code>

      *            の場合、ディスエーブル。

      */

     public void setEnabled(final boolean enabled) {

         if (this.enabled != enabled) {

             this.enabled = enabled;

             fireHandlerChanged(new HandlerEvent(this, true, false));

         }

     }

 }