/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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.apache.myfaces.el;
  
  import java.util.Iterator;
  
  import javax.faces.FactoryFinder;
  import javax.faces.event.PhaseEvent;
  import javax.faces.event.PhaseId;
  import javax.faces.event.PhaseListener;
  import javax.faces.lifecycle.LifecycleFactory;
  
  import org.apache.myfaces.el.unified.ELResolverBuilder;
  
  /**
   * The class will initialize the resolver for JSP
   * 
   * @author Mathias Broekelmann (latest modification by $Author$)
   * @version $Revision$ $Date$
   */
  public final class ResolverForJSPInitializer implements PhaseListener
  {
      private final ELResolverBuilder _resolverBuilder;
      private volatile boolean initialized;
      private final javax.el.CompositeELResolver _resolverForJSP;
  
      public ResolverForJSPInitializer(final ELResolverBuilder resolverBuilder,
                                       final javax.el.CompositeELResolver resolverForJSP)
      {
          _resolverBuilder = resolverBuilder;
          _resolverForJSP = resolverForJSP;
      }
  
      public void beforePhase(final PhaseEvent event)
      {
          if (!initialized)
          {
              synchronized(this)
              {
                  if (!initialized)
                  {
                      _resolverBuilder.build(_resolverForJSP);
  
                      LifecycleFactory factory = (LifecycleFactory) 
                              FactoryFinder.getFactory(FactoryFinder.LIFECYCLE_FACTORY);
                      for (Iterator<String> iter = factory.getLifecycleIds(); iter.hasNext();)
                      {
                          factory.getLifecycle(iter.next()).removePhaseListener(this);
                      }
                      
                      initialized = true;
                  }
              }
          }
      }
  
      public void afterPhase(final PhaseEvent event)
      {
      }
  
      public PhaseId getPhaseId()
      {
          return PhaseId.ANY_PHASE;
      }
  
  }