/*
    * 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 javax.faces.component;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.LinkedList;
  import java.util.List;
  import java.util.Locale;
  import java.util.Map;
  import java.util.logging.Level;
  import java.util.logging.Logger;
  
  import javax.el.MethodExpression;
  import javax.el.ValueExpression;
  import javax.faces.FactoryFinder;
  import javax.faces.application.ProjectStage;
  import javax.faces.context.FacesContext;
  import javax.faces.context.PartialViewContext;
  import javax.faces.event.AbortProcessingException;
  import javax.faces.event.ExceptionQueuedEvent;
  import javax.faces.event.ExceptionQueuedEventContext;
  import javax.faces.event.FacesEvent;
  import javax.faces.event.PhaseEvent;
  import javax.faces.event.PhaseId;
  import javax.faces.event.PhaseListener;
  import javax.faces.event.PostConstructViewMapEvent;
  import javax.faces.event.PreDestroyViewMapEvent;
  import javax.faces.event.SystemEvent;
  import javax.faces.event.SystemEventListener;
  import javax.faces.lifecycle.Lifecycle;
  import javax.faces.lifecycle.LifecycleFactory;
  import javax.faces.view.ViewDeclarationLanguage;
  import javax.faces.view.ViewMetadata;
  import javax.faces.webapp.FacesServlet;
  
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFComponent;
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFJspProperty;
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFProperty;
  
  /**
   * Creates a JSF View, which is a container that holds all of the components that are part of the view.
   * <p>
   * Unless otherwise specified, all attributes accept static values or EL expressions.
   * </p>
   * <p>
   * See the javadoc for this class in the <a href="http://java.sun.com/j2ee/javaserverfaces/1.2/docs/api/index.html">JSF
   * Specification</a> for further details.
   * </p>
   */
  @JSFComponent(name = "f:view", bodyContent = "JSP", tagClass = "org.apache.myfaces.taglib.core.ViewTag")
  @JSFJspProperty(name = "binding", returnType = "java.lang.String", tagExcluded = true)
  public class UIViewRoot extends UIComponentBase implements UniqueIdVendor
  {
      public static final String COMPONENT_FAMILY = "javax.faces.ViewRoot";
      public static final String COMPONENT_TYPE = "javax.faces.ViewRoot";
      public static final String METADATA_FACET_NAME = "javax_faces_metadata";
      public static final String UNIQUE_ID_PREFIX = "j_id";
      public static final String VIEW_PARAMETERS_KEY = "javax.faces.component.VIEW_PARAMETERS_KEY";
  
      private transient Logger logger = null;
  
      private static final PhaseProcessor APPLY_REQUEST_VALUES_PROCESSOR = new ApplyRequestValuesPhaseProcessor();
      private static final PhaseProcessor PROCESS_VALIDATORS_PROCESSOR = new ProcessValidatorPhaseProcessor();
      private static final PhaseProcessor UPDATE_MODEL_PROCESSOR = new UpdateModelPhaseProcessor();
  
      /**
       * The counter which will ensure a unique component id for every component instance in the tree that doesn't have an
       * id attribute set.
       */
      //private long _uniqueIdCounter = 0;
  
      // todo: is it right to save the state of _events and _phaseListeners?
      private List<FacesEvent> _events;
  
      /**
       * Map containing view scope objects. 
       * 
      * It is not expected this map hold PartialStateHolder instances,
      * so we can use saveAttachedState and restoreAttachedState methods.
      */
     private Map<String, Object> _viewScope;
 
     private transient Lifecycle _lifecycle = null;
     
     private HashMap<Class<? extends SystemEvent>, List<SystemEventListener>> _systemEventListeners;
     
     // Tracks success in the beforePhase. Listeners that threw an exception
     // in beforePhase or were never called, because a previous listener threw
     // an exception, should not have their afterPhase method called
     private transient Map<PhaseId, boolean[]> listenerSuccessMap;
     
     private static final String JAVAX_FACES_LOCATION_PREFIX = "javax_faces_location_";
     private static final String JAVAX_FACES_LOCATION_HEAD = "javax_faces_location_head";
     private static final String JAVAX_FACES_LOCATION_BODY = "javax_faces_location_body";
     private static final String JAVAX_FACES_LOCATION_FORM = "javax_faces_location_form";
     
     /**
      * Construct an instance of the UIViewRoot.
      */
     public UIViewRoot()
     {
         setRendererType(null);
     }
 
     /**
      * @since 2.0
      */
     public void addComponentResource(FacesContext context, UIComponent componentResource)
     {
         addComponentResource(context, componentResource, null);
     }
 
     /**
      * @since 2.0
      */
     public void addComponentResource(FacesContext context, UIComponent componentResource, String target)
     {
         // If the target argument is null
         if (target == null)
         {
             // Look for a target attribute on the component
             target = (String)componentResource.getAttributes().get("target");
 
             // If there is no target attribute, set target to be the default value head
             if (target == null)
             {
                 target = "head";
             }
         }
 
         // Call getComponentResources to obtain the child list for the given target
         List<UIComponent> componentResources = _getComponentResources(context, target);
 
         // If the component ID of componentResource matches the ID of a resource
         // that has already been added, remove the old resource.
         String componentId = componentResource.getId();
         
         if (componentId == null)
         {
             // componentResource can have no id - calling createUniqueId makes us sure that component will have one
             // https://issues.apache.org/jira/browse/MYFACES-2775
             componentId = createUniqueId(context, null);
             componentResource.setId(componentId);
         }
         
         // This var helps to handle the case when we try to add a component that already is
         // on the resource list, because PostAddToViewEvent also is sent to components 
         // backing resources. The problem start when a component is already inside
         // componentResources list and we try to relocate it again. This leads to a StackOverflowException
         // so we need to check if a component is and prevent remove and add it again. Note
         // that remove and then add a component trigger another PostAddToViewEvent. The right
         // point to prevent this StackOverflowException is here, because this method is 
         // responsible to traverse the componentResources list and add when necessary.
         boolean alreadyAdded = false;
 
         //The check is only necessary if the component resource is part of the tree.
         if (componentResource.isInView())
         {
             if (componentResource.getParent() != null &&
                 componentResource.getParent().getId() != null &&
                 componentResource.getParent().getId().equals(JAVAX_FACES_LOCATION_PREFIX + target))
             {
                 // We can assume safely that the component is in place, because there is no way to 
                 // put a component resource on a component resource container without call addComponentResource
                 // so relocation here will not happen.
                 alreadyAdded = true;
             }
             else if (componentId != null)
             {
                 for(Iterator<UIComponent> it = componentResources.iterator(); it.hasNext();)
                 {
                     UIComponent component = it.next();
                     if(componentId.equals(component.getId()) && componentResource != component)
                     {
                         it.remove();
                     }
                     else if (componentResource == component)
                     {
                         alreadyAdded = true;
                     }
                 }
             }
         }
         else if (componentId != null)
         {
             for(Iterator<UIComponent> it = componentResources.iterator(); it.hasNext();)
             {
                 UIComponent component = it.next();
                 if(componentId.equals(component.getId()) && componentResource != component)
                 {
                     it.remove();
                 }
                 else if (componentResource == component)
                 {
                     alreadyAdded = true;
                 }
             }
         }
         
         // Add the component resource to the list
         if (!alreadyAdded)
         {
             componentResources.add(componentResource);
         }
     }
 
     /**
      * Adds a The phaseListeners attached to ViewRoot.
      */
     public void addPhaseListener(PhaseListener phaseListener)
     {
         if (phaseListener == null)
         {
             throw new NullPointerException("phaseListener");
         }
         
         getStateHelper().add(PropertyKeys.phaseListeners, phaseListener);
     }
 
     /**
      * @since 2.0
      */
     public void broadcastEvents(FacesContext context, PhaseId phaseId)
     {
         if (_events == null)
         {
             return;
         }
         
         Events events = _getEvents(phaseId);
         
         // Spec. 3.4.2.6 Event Broadcasting:
         // Queue one or more additional events, from the same source
         // component or a different one, for processing during the
         // current lifecycle phase.
         
         // Unfortunately with that requirement it is easy to create infinite loop in processing. One example can be:
         //
         // public processAction(ActionEvent actionEvent)
         // {
         // actionEvent  = new ActionEvent(actionEvent.getComponent());
         // actionEvent.queue();
         // }
         // 
         // Thus we iterate here only 15x. If iteration overreachs 15 we output a warning  
         
         int loops = 0;
         int maxLoops = 15;
         Collection<FacesEvent> eventsAborted = new LinkedList<FacesEvent>(); 
         do
         {
             // First broadcast events that have been queued for PhaseId.ANY_PHASE.
             boolean noUnexpectedException = _broadcastAll(context, events.getAnyPhase(), eventsAborted);
             if (!noUnexpectedException)
             {
                 return;
             }
             List<FacesEvent> eventsOnPhase = events.getOnPhase();
             if (!eventsAborted.isEmpty())
             {
                 eventsOnPhase.removeAll(eventsAborted);
                 eventsAborted.clear();
             }
             noUnexpectedException = _broadcastAll(context, eventsOnPhase, eventsAborted);
             if (!noUnexpectedException)
             {
                 return;
             }
 
             events = _getEvents(phaseId);
             loops++;
             
         } while (events.hasMoreEvents() && loops < maxLoops);
         
         if (loops == maxLoops && events.hasMoreEvents())
         {
             // broadcast reach maxLoops - probably a infinitive recursion:
             boolean production = getFacesContext().isProjectStage(ProjectStage.Production);
             Level level = production ? Level.FINE : Level.WARNING;
             if (_getLogger().isLoggable(level))
             {
                 List<String> name = new ArrayList<String>(events.getAnyPhase().size() + events.getOnPhase().size());
                 for (FacesEvent facesEvent : events.getAnyPhase())
                 {
                     String clientId = facesEvent.getComponent().getClientId(getFacesContext());
                     name.add(clientId);
                 }
                 for (FacesEvent facesEvent : events.getOnPhase())
                 {
                     String clientId = facesEvent.getComponent().getClientId(getFacesContext());
                     name.add(clientId);
                 }
                 _getLogger().log(level,
                         "Event broadcating for PhaseId {0} at UIViewRoot {1} reaches maximal limit, please check " +
                         "listeners for infinite recursion. Component id: {2}",
                         new Object [] {phaseId, getViewId(), name});
             }
         }
     }
 
 
     /**
      * Provides a unique id for this component instance.
      */
     public String createUniqueId()
     {
         return createUniqueId(getFacesContext(), null);
     }
 
     /**
      * 
      * {@inheritDoc}
      * 
      * @since 2.0
      */
     public String createUniqueId(FacesContext context, String seed)
     {
         StringBuilder bld = _getSharedStringBuilder(context);
 
         // Generate an identifier for a component. The identifier will be prefixed with
         // UNIQUE_ID_PREFIX, and will be unique within this UIViewRoot.
         if(seed==null)
         {
             Long uniqueIdCounter = (Long) getStateHelper().get(PropertyKeys.uniqueIdCounter);
             uniqueIdCounter = (uniqueIdCounter == null) ? 0 : uniqueIdCounter;
             getStateHelper().put(PropertyKeys.uniqueIdCounter, (uniqueIdCounter+1L));
             return bld.append(UNIQUE_ID_PREFIX).append(uniqueIdCounter).toString();    
         }
         // Optionally, a unique seed value can be supplied by component creators which
         // should be included in the generated unique id.
         else
         {
             return bld.append(UNIQUE_ID_PREFIX).append(seed).toString();
         }
     }
 
     @Override
     public void encodeBegin(FacesContext context) throws IOException
     {
         checkNull(context, "context");
 
         boolean skipPhase = false;
 
         try
         {
             skipPhase = notifyListeners(context, PhaseId.RENDER_RESPONSE, getBeforePhaseListener(), true);
         }
         catch (Exception e)
         {
             // following the spec we have to swallow the exception
             _getLogger().log(Level.SEVERE, "Exception while processing phase listener: " + e.getMessage(), e);
         }
 
         if (!skipPhase)
         {
             //prerendering happens, we now publish the prerender view event
             //the specs states that the viewroot as source is about to be rendered
             //hence we issue the event immediately before publish, if the phase is not skipped
             //context.getApplication().publishEvent(context, PreRenderViewEvent.class, this);
             //then the view rendering is about to begin
             super.encodeBegin(context);
         }
         else
         {
             pushComponentToEL(context, this);
         }
     }
 
     /**
      * @since 2.0
      */
     @Override
     public void encodeChildren(FacesContext context) throws IOException
     {
         if (context.getResponseComplete())
         {
             return;
         }
         PartialViewContext pContext = context.getPartialViewContext();
         
         // If PartialViewContext.isAjaxRequest() returns true
         if (pContext.isAjaxRequest())
         {
             // Perform partial rendering by calling PartialViewContext.processPartial() with PhaseId.RENDER_RESPONSE.
             //sectin 13.4.3 of the jsf2 specification
             pContext.processPartial(PhaseId.RENDER_RESPONSE);
         }
         else
         {
             // If PartialViewContext.isAjaxRequest() returns false
             // delegate to super.encodeChildren(javax.faces.context.FacesContext) method.
             super.encodeChildren(context);
         }
     }
 
     @Override
     public void encodeEnd(FacesContext context) throws IOException
     {
         checkNull(context, "context");
 
         if (!context.getResponseComplete())
         {
             super.encodeEnd(context);
             
             // the call to encodeAll() on every UIViewParameter here is only necessary
             // if the current request is _not_ an AJAX request, because if it was an
             // AJAX request, the call would already have happened in PartialViewContextImpl and
             // would anyway be too late here, because the state would already have been generated
             PartialViewContext partialContext = context.getPartialViewContext();
             if (!partialContext.isAjaxRequest())
             {
                 ViewDeclarationLanguage vdl
                         = context.getApplication().getViewHandler().getViewDeclarationLanguage(context, getViewId());
                 if (vdl != null)
                 {
                     // If the current view has view parameters, as indicated by a non-empty
                     // and non-UnsupportedOperationException throwing
                     // return from ViewDeclarationLanguage.getViewMetadata(javax.faces.context.FacesContext, String)
                     ViewMetadata metadata = null;
                     try
                     {
                         metadata = vdl.getViewMetadata(context, getViewId());    
                     }
                     catch(UnsupportedOperationException e)
                     {
                         _getLogger().log(Level.SEVERE, "Exception while obtaining the view metadata: " +
                                 e.getMessage(), e);
                     }
                     
                     if (metadata != null)
                     {
                         try
                         {
                             Collection<UIViewParameter> viewParams = ViewMetadata.getViewParameters(this);    
                             if(!viewParams.isEmpty())
                             {
                                 // call UIViewParameter.encodeAll(javax.faces.context.FacesContext) on each parameter.
                                 for(UIViewParameter param : viewParams)
                                 {
                                     param.encodeAll(context);
                                 }
                             }
                         }
                         catch(UnsupportedOperationException e)
                         {
                             // If calling getViewParameters() causes UnsupportedOperationException
                             // to be thrown, the exception must be silently swallowed.
                         }
                     }
                 }
             }
         }
         
         try
         {
             notifyListeners(context, PhaseId.RENDER_RESPONSE, getAfterPhaseListener(), false);
         }
         catch (Exception e)
         {
             // following the spec we have to swallow the exception
             _getLogger().log(Level.SEVERE, "Exception while processing phase listener: " + e.getMessage(), e);
         }
     }
 
     /**
      * MethodBinding pointing to a method that takes a javax.faces.event.PhaseEvent and returns void, called after every
      * phase except for restore view.
      *
      * @return the new afterPhaseListener value
      */
     @JSFProperty(returnSignature = "void", methodSignature = "javax.faces.event.PhaseEvent",
                  jspName = "afterPhase", stateHolder=true)
     public MethodExpression getAfterPhaseListener()
     {
         return (MethodExpression) getStateHelper().eval(PropertyKeys.afterPhaseListener);
     }
 
     /**
      * MethodBinding pointing to a method that takes a javax.faces.event.PhaseEvent and returns void, called before
      * every phase except for restore view.
      *
      * @return the new beforePhaseListener value
      */
     @JSFProperty(returnSignature = "void", methodSignature = "javax.faces.event.PhaseEvent",
                  jspName = "beforePhase", stateHolder=true)
     public MethodExpression getBeforePhaseListener()
     {
         return (MethodExpression) getStateHelper().eval(PropertyKeys.beforePhaseListener);
     }
 
     /**
      * DO NOT USE.
      * <p>
      * As this component has no "id" property, it has no clientId property either.
      */
     @Override
     public String getClientId(FacesContext context)
     {
         return super.getClientId(context);
         // Call parent method due to TCK problems
         // return null;
     }
 
     /**
      * @since 2.0
      */
     public List<UIComponent> getComponentResources(FacesContext context, String target)
     {
         // Locate the facet for the component by calling getFacet() using target as the argument
         UIComponent facet = getFacet(target);
 
         /*
         // If the facet is not found,
         if (facet == null)
         {
             // create the facet by calling context.getApplication().createComponent()
             // using javax.faces.Panel as the argument
             facet = context.getApplication().createComponent("javax.faces.Panel");
 
             // Set the id of the facet to be target
             facet.setId(target);
 
             // Add the facet to the facets Map using target as the key
             getFacets().put(target, facet);
         }
 
         // Return the children of the facet
         // The API doc indicates that this method should "Return an unmodifiable
         // List of UIComponents for the provided target argument."
         // and also that "If no children are found for the facet, return Collections.emptyList()."
         List<UIComponent> children = facet.getChildren();
         return ( children == null ? Collections.<UIComponent>emptyList() : Collections.unmodifiableList(children) );
         */
         if (facet != null)
         {
             if (facet.getChildCount() > 0)
             {
                 return Collections.unmodifiableList(facet.getChildren());
             }
             else
             {
                 return Collections.<UIComponent>emptyList();
             }
         }
         return Collections.<UIComponent>emptyList();
     }
     
     private List<UIComponent> _getComponentResources(FacesContext context, String target)
     {
         // Locate the facet for the component by calling getFacet() using target as the argument
         UIComponent facet = getFacet(target);
 
         // If the facet is not found,
         if (facet == null)
         {
             // create the facet by calling context.getApplication().createComponent()
             // using javax.faces.Panel as the argument
             facet = context.getApplication().createComponent("javax.faces.ComponentResourceContainer");
 
             // Set the id of the facet to be target
             if (target.equals("head"))
             {
                 facet.setId(JAVAX_FACES_LOCATION_HEAD);
             }
             else if (target.equals("body"))
             {
                 facet.setId(JAVAX_FACES_LOCATION_BODY);
             }
             else if (target.equals("form"))
             {
                 facet.setId(JAVAX_FACES_LOCATION_FORM);
             }
             else
             {
                 facet.setId(JAVAX_FACES_LOCATION_PREFIX + target);
             }
             
             // From jsr-314-open list it was made clear this facet is transient,
             // because all component resources does not change its inner state between
             // requests
             //
             // MYFACES-3047 It was found that resources added using ResourceDependency annotation
             // requires to be saved and restored, so it is not possible to mark this facets
             // as transient. The previous statement is true only for PSS.
             //facet.setTransient(true);
 
             // Add the facet to the facets Map using target as the key
             getFacets().put(target, facet);
         }
         return facet.getChildren();
     }
 
     @Override
     public String getFamily()
     {
         return COMPONENT_FAMILY;
     }
 
     /**
      * The locale for this view.
      * <p>
      * Defaults to the default locale specified in the faces configuration file.
      * </p>
      */
     @JSFProperty
     public Locale getLocale()
     {
         Object locale = getStateHelper().get(PropertyKeys.locale);
         if (locale != null)
         {
             return (Locale)locale;
         }
         ValueExpression expression = getValueExpression(PropertyKeys.locale.toString());
         if (expression != null)
         {
             Object veLocale = expression.getValue(getFacesContext().getELContext());
             if (veLocale instanceof Locale)
             {
                 return (Locale) veLocale;
             }
             else
             {
                 return (Locale) _LocaleUtils.toLocale(veLocale.toString());
             }
         }
         else
         {
             locale = getFacesContext().getApplication().getViewHandler().calculateLocale(getFacesContext());
 
             if (locale instanceof Locale)
             {
                 return (Locale)locale;
             }
             else if (locale instanceof String)
             {
                 return _LocaleUtils.toLocale((String)locale);
             }
         }
 
         return getFacesContext().getApplication().getViewHandler().calculateLocale(getFacesContext());
     }
 
     /**
      * @since 2.0
      */
     public List<PhaseListener> getPhaseListeners()
     {
         List<PhaseListener> listeners = (List<PhaseListener>) getStateHelper().get(PropertyKeys.phaseListeners);
         if (listeners == null)
         {
             listeners = Collections.emptyList();
         }
         else
         {
             listeners = Collections.unmodifiableList(listeners);
         }
 
         return listeners;
     }
 
     /**
      * Defines what renderkit should be used to render this view.
      */
     @JSFProperty
     public String getRenderKitId()
     {
         return (String) getStateHelper().eval(PropertyKeys.renderKitId);
     }
 
     /**
      * @since 2.0
      */
     @Override
     public boolean getRendersChildren()
     {
         // Call UIComponentBase.getRendersChildren() 
         // If PartialViewContext.isAjaxRequest()  returns true this method must return true.
         PartialViewContext context = getFacesContext().getPartialViewContext();
 
         return (context.isAjaxRequest()) ? true : super.getRendersChildren();
     }
 
     /**
      * A unique identifier for the "template" from which this view was generated.
      * <p>
      * Typically this is the filesystem path to the template file, but the exact details are the responsibility of the
      * current ViewHandler implementation.
      */
     @JSFProperty(tagExcluded = true)
     public String getViewId()
     {
         return (String) getStateHelper().get(PropertyKeys.viewId);
     }
 
     /**
      * @since 2.0
      */
     public Map<String, Object> getViewMap()
     {
         return this.getViewMap(true);
     }
 
     /**
      * @since 2.0
      */
     public Map<String, Object> getViewMap(boolean create)
     {
         if (_viewScope == null && create)
         {
             _viewScope = new ViewScope();
             FacesContext facesContext = getFacesContext();
             facesContext.getApplication().publishEvent(facesContext, PostConstructViewMapEvent.class, this);
         }
 
         return _viewScope;
     }
     
     /**
      * {@inheritDoc}
      */
     @Override
     public boolean isInView()
     {
         return true;
     }
 
     public void processApplication(final FacesContext context)
     {
         checkNull(context, "context");
         _process(context, PhaseId.INVOKE_APPLICATION, null);
     }
 
     @Override
     public void processDecodes(FacesContext context)
     {
         checkNull(context, "context");
         _process(context, PhaseId.APPLY_REQUEST_VALUES, APPLY_REQUEST_VALUES_PROCESSOR);
     }
 
     /**
      * @since 2.0
      */
     @Override
     public void processRestoreState(FacesContext context, Object state)
     {
         // The default implementation must call UIComponentBase.processRestoreState(javax.faces.context.FacesContext,
         // java.lang.Object) from within a try block.
         try
         {
             super.processRestoreState(context, state);
         }
         finally
         {
             // The try block must have a finally block that ensures that no FacesEvents remain in the event queue
             broadcastEvents(context, PhaseId.RESTORE_VIEW);
 
             //visitTree(VisitContext.createVisitContext(context), new RestoreStateCallback());
         }
     }
 
     @Override
     public void queueEvent(FacesEvent event)
     {
         checkNull(event, "event");
         if (_events == null)
         {
             _events = new ArrayList<FacesEvent>();
         }
 
         _events.add(event);
     }
 
     @Override
     public void processValidators(FacesContext context)
     {
         checkNull(context, "context");
         _process(context, PhaseId.PROCESS_VALIDATIONS, PROCESS_VALIDATORS_PROCESSOR);
     }
 
     @Override
     public void processUpdates(FacesContext context)
     {
         checkNull(context, "context");
         _process(context, PhaseId.UPDATE_MODEL_VALUES, UPDATE_MODEL_PROCESSOR);
     }
 
     public void setLocale(Locale locale)
     {
         getStateHelper().put(PropertyKeys.locale, locale );
     }
 
     /**
      * Invoke view-specific phase listeners, plus an optional EL MethodExpression.
      * <p>
      * JSF1.2 adds the ability for PhaseListener objects to be added to a UIViewRoot instance, and for
      * "beforePhaseListener" and "afterPhaseListener" EL expressions to be defined on the viewroot. This method is
      * expected to be called at appropriate times, and will then execute the relevant listener callbacks.
      * <p>
      * Parameter "listener" may be null. If not null, then it is an EL expression pointing to a user method that will be
      * invoked.
      * <p>
      * Note that the global PhaseListeners are invoked via the Lifecycle implementation, not from this method here.
      * <p>
      * These PhaseListeners are processed with the same rules as the globally defined PhaseListeners, except
      * that any Exceptions, which may occur during the execution of the PhaseListeners, will only be logged
      * and not published to the ExceptionHandler.
      */
     private boolean notifyListeners(FacesContext context, PhaseId phaseId, MethodExpression listener,
                                     boolean beforePhase)
     {
         List<PhaseListener> phaseListeners = (List<PhaseListener>) getStateHelper().get(PropertyKeys.phaseListeners);
         if (listener != null || (phaseListeners != null && !phaseListeners.isEmpty()))
         {
             // how many listeners do we have? (the MethodExpression listener is counted in either way)
             // NOTE: beforePhaseSuccess[0] always refers to the MethodExpression listener
             int listenerCount = (phaseListeners != null ? phaseListeners.size() + 1 : 1);
             
             boolean[] beforePhaseSuccess;
             if (beforePhase)
             {
                 beforePhaseSuccess = new boolean[listenerCount];
                 _getListenerSuccessMap().put(phaseId, beforePhaseSuccess);
             }
             else
             {
                 // afterPhase - get beforePhaseSuccess from the Map
                 beforePhaseSuccess = _getListenerSuccessMap().get(phaseId);
                 if (beforePhaseSuccess == null)
                 {
                     // no Map available - assume that everything went well
                     beforePhaseSuccess = new boolean[listenerCount];
                     Arrays.fill(beforePhaseSuccess, true);
                 }
             }
             
             PhaseEvent event = createEvent(context, phaseId);
 
             // only invoke the listener if we are in beforePhase
             // or if the related before PhaseListener finished without an Exception
             if (listener != null && (beforePhase || beforePhaseSuccess[0]))
             {
                 try
                 {
                     listener.invoke(context.getELContext(), new Object[] { event });
                     beforePhaseSuccess[0] = true;
                 }
                 catch (Throwable t) 
                 {
                     beforePhaseSuccess[0] = false; // redundant - for clarity
                     _getLogger().log(Level.SEVERE, "An Exception occured while processing " +
                                              listener.getExpressionString() + 
                                              " in Phase " + phaseId, t);
                     if (beforePhase)
                     {
                         return context.getResponseComplete() ||
                                 (context.getRenderResponse() && !PhaseId.RENDER_RESPONSE.equals(phaseId));
                     }
                 }
             }
             else if (beforePhase)
             {
                 // there is no beforePhase MethodExpression listener
                 beforePhaseSuccess[0] = true;
             }
 
             if (phaseListeners != null && !phaseListeners.isEmpty())
             {
                 if (beforePhase)
                 {
                     // process listeners in ascending order
                     for (int i = 0; i < beforePhaseSuccess.length - 1; i++)
                     {
                         PhaseListener phaseListener;
                         try 
                         {
                             phaseListener = phaseListeners.get(i);
                         }
                         catch (IndexOutOfBoundsException e)
                         {
                             // happens when a PhaseListener removes another PhaseListener 
                             // from UIViewRoot in its beforePhase method
                             throw new IllegalStateException("A PhaseListener must not remove " +
                                     "PhaseListeners from UIViewRoot.");
                         }
                         PhaseId listenerPhaseId = phaseListener.getPhaseId();
                         if (phaseId.equals(listenerPhaseId) || PhaseId.ANY_PHASE.equals(listenerPhaseId))
                         {
                             try
                             {
                                 phaseListener.beforePhase(event);
                                 beforePhaseSuccess[i + 1] = true;
                             }
                             catch (Throwable t) 
                             {
                                 beforePhaseSuccess[i + 1] = false; // redundant - for clarity
                                 _getLogger().log(Level.SEVERE, "An Exception occured while processing the " +
                                                          "beforePhase method of PhaseListener " + phaseListener +
                                                          " in Phase " + phaseId, t);
                                 return context.getResponseComplete() ||
                                         (context.getRenderResponse() && !PhaseId.RENDER_RESPONSE.equals(phaseId));
                             }
                         }
                     }
                 }
                 else
                 {
                     // afterPhase
                     // process listeners in descending order
                     for (int i = beforePhaseSuccess.length - 1; i > 0; i--)
                     {
                         PhaseListener phaseListener;
                         try 
                         {
                             phaseListener = phaseListeners.get(i - 1);
                         }
                         catch (IndexOutOfBoundsException e)
                         {
                             // happens when a PhaseListener removes another PhaseListener 
                             // from UIViewRoot in its beforePhase or afterPhase method
                             throw new IllegalStateException("A PhaseListener must not remove " +
                                     "PhaseListeners from UIViewRoot.");
                         }
                         PhaseId listenerPhaseId = phaseListener.getPhaseId();
                         if ((phaseId.equals(listenerPhaseId) || PhaseId.ANY_PHASE.equals(listenerPhaseId))
                                 && beforePhaseSuccess[i])
                         {
                             try
                             {
                                 phaseListener.afterPhase(event);
                             }
                             catch (Throwable t) 
                             {
                                 logger.log(Level.SEVERE, "An Exception occured while processing the " +
                                                          "afterPhase method of PhaseListener " + phaseListener +
                                                          " in Phase " + phaseId, t);
                             }
                         }
                     }
                 }
             }
         }
 
         if (beforePhase)
         {
             return context.getResponseComplete() ||
                     (context.getRenderResponse() && !PhaseId.RENDER_RESPONSE.equals(phaseId));
         }
         else
         {
             return context.getResponseComplete() || context.getRenderResponse();
         }
     }
 
     private PhaseEvent createEvent(FacesContext context, PhaseId phaseId)
     {
         if (_lifecycle == null)
         {
             LifecycleFactory factory = (LifecycleFactory)FactoryFinder.getFactory(FactoryFinder.LIFECYCLE_FACTORY);
             String id = context.getExternalContext().getInitParameter(FacesServlet.LIFECYCLE_ID_ATTR);
             if (id == null)
             {
                 id = LifecycleFactory.DEFAULT_LIFECYCLE;
             }
             _lifecycle = factory.getLifecycle(id);
         }
         return new PhaseEvent(context, phaseId, _lifecycle);
     }
 
     /**
      * Broadcast all events in the specified collection, stopping the at any time an AbortProcessingException
      * is thrown.
      *
      * @param context the current JSF context
      * @param events the events to broadcast
      * @return 
      *
      * @return <code>true</code> if the broadcast was completed without unexpected abortion/exception,
      *  <code>false</code> otherwise
      */
     private boolean _broadcastAll(FacesContext context,
                                List<? extends FacesEvent> events,
                                Collection<FacesEvent> eventsAborted)
     {
         assert events != null;
 
         for (int i = 0; i < events.size(); i++)
         {
             FacesEvent event = events.get(i);
             UIComponent source = event.getComponent();
             UIComponent compositeParent = UIComponent.getCompositeComponentParent(source);
             if (compositeParent != null)
             {
                 pushComponentToEL(context, compositeParent);
             }
             // Push the source as the current component
             pushComponentToEL(context, source);
 
             try
             {
                 // Actual event broadcasting
                 if (!source.isCachedFacesContext())
                 {
                     try
                     {
                         source.setCachedFacesContext(context);
                         source.broadcast(event);
                     }
                     finally
                     {
                         source.setCachedFacesContext(null);
                     }
                 }
                 else
                 {
                     source.broadcast(event);
                 }
             }
             catch (Exception e)
             {
 
                 Throwable cause = e;
                 AbortProcessingException ape = null;
                 do
                 {
                     if (cause != null && cause instanceof AbortProcessingException)
                     {
                         ape = (AbortProcessingException) cause;
                         break;
                     }
                     cause = cause.getCause();
                 }
                 while (cause != null);
                 
                 // for any other exception publish ExceptionQueuedEvent
                 // publish the Exception to be handled by the ExceptionHandler
                 // to publish or to not publish APE? That is the question : MYFACES-3199. We publish it,
                 // because user can handle it in custom exception handler then. 
                 if (ape != null)
                 {
                     e = ape;
                 }
                 ExceptionQueuedEventContext exceptionContext 
                         = new ExceptionQueuedEventContext(context, e, source, context.getCurrentPhaseId());
                 context.getApplication().publishEvent(context, ExceptionQueuedEvent.class, exceptionContext);
 
                 
                 if (ape != null)
                 {
                     // APE found,  abortion for this event only
                     eventsAborted.add(event);
                 }
                 else
                 {
                     // We can't continue broadcast processing if other exception is thrown:
                     return false;
                 }
             }
             finally
             {
                 // Restore the current component
                 source.popComponentFromEL(context);
                 if (compositeParent != null)
                 {
                     compositeParent.popComponentFromEL(context);
                 }
             }
         }
         return true;
     }
 
     private void clearEvents()
     {
         _events = null;
     }
 
     private void checkNull(Object value, String valueLabel)
     {
         if (value == null)
         {
             throw new NullPointerException(valueLabel + " is null");
         }
     }
 
     public void setRenderKitId(String renderKitId)
     {
         getStateHelper().put(PropertyKeys.renderKitId, renderKitId );
     }
 
     /**
      * DO NOT USE.
      * <p>
      * This inherited property is disabled. Although this class extends a base-class that defines a read/write rendered
      * property, this particular subclass does not support setting it. Yes, this is broken OO design: direct all
      * complaints to the JSF spec group.
      */
     @Override
     @JSFProperty(tagExcluded = true)
     public void setRendered(boolean state)
     {
         // Call parent method due to TCK problems
         super.setRendered(state);
         // throw new UnsupportedOperationException();
     }
 
     /**
      * DO NOT USE.
      * <p>
      * Although this class extends a base-class that defines a read/write id property, it makes no sense for this
      * particular subclass to support it. The tag library does not export this property for use, but there is no way to
      * "undeclare" a java method. Yes, this is broken OO design: direct all complaints to the JSF spec group.
      * <p>
      * This property should be disabled (ie throw an exception if invoked). However there are currently several places
      * that call this method (eg during restoreState) so it just does the normal thing for the moment. TODO: fix callers
      * then make this throw an exception.
      *
      * @JSFProperty tagExcluded="true"
      */
     @Override
     public void setId(String id)
     {
         // throw new UnsupportedOperationException();
 
         // Leave enabled for now. Things like the TreeStructureManager call this,
         // even though they probably should not.
         super.setId(id);
     }
     
     /**
      * {@inheritDoc}
      */
     @Override
     public void setInView(boolean isInView)
     {
         // no-op view root is always in view
     }
 
     public void removeComponentResource(FacesContext context, UIComponent componentResource)
     {
         removeComponentResource(context, componentResource, null);
     }
 
     public void removeComponentResource(FacesContext context, UIComponent componentResource, String target)
     {
         // If the target argument is null
         if (target == null)
         {
             // Look for a target attribute on the component
             target = (String)componentResource.getAttributes().get("target");
 
             // If there is no target attribute
             if (target == null)
             {
                 // Set target to be the default value head
                 target = "head";
             }
         }
 
 
         // Call getComponentResources to obtain the child list for the given target.
         //List<UIComponent> componentResources = getComponentResources(context, target);
         UIComponent facet = getFacet(target);
         if (facet != null)
         {
             //Only if the facet is found it is possible to remove the resource,
             //otherwise nothing should happen (call to getComponentResource trigger
             //creation of facet)
             // Remove the component resource from the child list
             facet.getChildren().remove(componentResource);
         }
     }
 
     public void setViewId(String viewId)
     {
         // It really doesn't make much sense to allow null here.
         // However the TCK does not check for it, and sun's implementation
         // allows it so here we allow it too.
         getStateHelper().put(PropertyKeys.viewId, viewId );
     }
 
     /**
      * Removes a The phaseListeners attached to ViewRoot.
      */
     public void removePhaseListener(PhaseListener phaseListener)
     {
         if (phaseListener == null)
         {
             return;
         }
 
         getStateHelper().remove(PropertyKeys.phaseListeners, phaseListener);
     }
 
     /**
      * Sets
      *
      * @param beforePhaseListener
      *            the new beforePhaseListener value
      */
     public void setBeforePhaseListener(MethodExpression beforePhaseListener)
     {
         getStateHelper().put(PropertyKeys.beforePhaseListener, beforePhaseListener);
     }
 
     /**
      * Sets
      *
      * @param afterPhaseListener
      *            the new afterPhaseListener value
      */
     public void setAfterPhaseListener(MethodExpression afterPhaseListener)
     {
         getStateHelper().put(PropertyKeys.afterPhaseListener, afterPhaseListener);
     }
     
     enum PropertyKeys
     {
          afterPhaseListener
         , beforePhaseListener
         , phaseListeners
         , locale
         , renderKitId
         , viewId
         , uniqueIdCounter
     }
     
     @Override
     public Object saveState(FacesContext facesContext)
     {
         if (initialStateMarked())
         {
             Object parentSaved = super.saveState(facesContext);
             if (parentSaved == null && _viewScope == null)
             {
                 //No values
                 return null;
             }
             else if (parentSaved == null && _viewScope != null && _viewScope.size() == 0)
             {
                 //Empty view scope, no values
                 return null;
             }
             
             Object[] values = new Object[2];
             values[0] = parentSaved;
             values[1] = saveAttachedState(facesContext,_viewScope);
             return values;
         }
         else
         {
             Object[] values = new Object[2];
             values[0] = super.saveState(facesContext);
             values[1] = saveAttachedState(facesContext,_viewScope);
             return values;
         }
     }
 
     @SuppressWarnings("unchecked")
     @Override
     public void restoreState(FacesContext facesContext, Object state)
     {
         if (state == null)
         {
             return;
         }
         
         Object[] values = (Object[])state;
         super.restoreState(facesContext,values[0]);
         _viewScope = (Map<String, Object>) restoreAttachedState(facesContext, values[1]);
     }
     
     public List<SystemEventListener> getViewListenersForEventClass(Class<? extends SystemEvent> systemEvent)
     {
         checkNull (systemEvent, "systemEvent");
         if (_systemEventListeners == null)
         {
             return null;
         }
         return _systemEventListeners.get (systemEvent);
     }
     
     public void subscribeToViewEvent(Class<? extends SystemEvent> systemEvent,
             SystemEventListener listener)
     {
         List<SystemEventListener> listeners;
         
         checkNull (systemEvent, "systemEvent");
         checkNull (listener, "listener");
         
         if (_systemEventListeners == null)
         {
             _systemEventListeners = new HashMap<Class<? extends SystemEvent>, List<SystemEventListener>>();
         }
         
         listeners = _systemEventListeners.get (systemEvent);
         
         if (listeners == null)
         {
             listeners = new ArrayList<SystemEventListener>();
             
             _systemEventListeners.put (systemEvent, listeners);
         }
         
         listeners.add (listener);
     }
     
     public void unsubscribeFromViewEvent(Class<? extends SystemEvent> systemEvent,
             SystemEventListener listener)
     {
         List<SystemEventListener> listeners;
         
         checkNull (systemEvent, "systemEvent");
         checkNull (listener, "listener");
         
         if (_systemEventListeners == null)
         {
             return;
         }
         
         listeners = _systemEventListeners.get (systemEvent);
         
         if (listeners != null)
         {
             listeners.remove (listener);
         }
     }
 
     /**
      * Process the specified phase by calling PhaseListener.beforePhase for every phase listeners defined on this
      * view root, then calling the process method of the processor, broadcasting relevant events and finally
      * notifying the afterPhase method of every phase listeners registered on this view root.
      *
      * @param context
      * @param phaseId
      * @param processor
      * @param broadcast
      *
      * @return
      */
     private boolean _process(FacesContext context, PhaseId phaseId, PhaseProcessor processor)
     {
         RuntimeException processingException = null;
         try
         {
             if (!notifyListeners(context, phaseId, getBeforePhaseListener(), true))
             {
                 try
                 {
                     if (processor != null)
                     {
                         processor.process(context, this);
                     }
         
                     broadcastEvents(context, phaseId);
                 }
                 catch (RuntimeException re)
                 {
                     // catch any Exception that occures while processing the phase
                     // to ensure invocation of the afterPhase methods
                     processingException = re;
                 }
             }
         }
         finally
         {
             if (context.getRenderResponse() || context.getResponseComplete())
             {
                 clearEvents();
             }            
         }
 
         boolean retVal = notifyListeners(context, phaseId, getAfterPhaseListener(), false);
         if (processingException == null) 
         {
             return retVal;   
         }
         else
         {
             throw processingException;
         }
     }
 
     private void _processDecodesDefault(FacesContext context)
     {
         super.processDecodes(context);
     }
 
     private void _processUpdatesDefault(FacesContext context)
     {
         super.processUpdates(context);
     }
 
     private void _processValidatorsDefault(FacesContext context)
     {
         super.processValidators(context);
     }
 
     /**
      * Gathers all event for current and ANY phase
      * @param phaseId current phase id
      */
     private Events _getEvents(PhaseId phaseId)
     {
         // Gather the events and purge the event list to prevent concurrent modification during broadcasting
         int size = _events.size();
         List<FacesEvent> anyPhase = new ArrayList<FacesEvent>(size);
         List<FacesEvent> onPhase = new ArrayList<FacesEvent>(size);
         
         for (int i = 0; i < size; i++)
         {
             FacesEvent event = _events.get(i);
             if (event.getPhaseId().equals(PhaseId.ANY_PHASE))
             {
                 anyPhase.add(event);
                 _events.remove(i);
                 size--;
                 i--;
             }
             else if (event.getPhaseId().equals(phaseId))
             {
                 onPhase.add(event);
                 _events.remove(i);
                 size--;
                 i--;
             }
         }
         
         return new Events(anyPhase, onPhase);
     }
     
     private Logger _getLogger()
     {
         if (logger == null)
         {
             logger = Logger.getLogger(UIViewRoot.class.getName());
         }
         return logger;
     }
 
     private Map<PhaseId, boolean[]> _getListenerSuccessMap()
     {
         // lazy init: 
         if (listenerSuccessMap == null)
         {
             listenerSuccessMap = new HashMap<PhaseId, boolean[]>();
         }
         return listenerSuccessMap;
     }
 
     private static interface PhaseProcessor
     {
         public void process(FacesContext context, UIViewRoot root);
     }
 
     private static class ApplyRequestValuesPhaseProcessor implements PhaseProcessor
     {
         public void process(FacesContext context, UIViewRoot root)
         {
             PartialViewContext pvc = context.getPartialViewContext();
             // Perform partial processing by calling PartialViewContext.processPartial(javax.faces.event.PhaseId)
             // with PhaseId.UPDATE_MODEL_VALUES if:
             //   * PartialViewContext.isPartialRequest() returns true and we don't have a request to process all
             // components in the view (PartialViewContext.isExecuteAll() returns false)
             //section 13.4.2 from the  JSF2  spec also see https://issues.apache.org/jira/browse/MYFACES-2119
             if (pvc.isPartialRequest() && !pvc.isExecuteAll())
             {
                 pvc.processPartial(PhaseId.APPLY_REQUEST_VALUES);
             }
             // Perform full processing by calling UIComponentBase.processUpdates(javax.faces.context.FacesContext)
             // if one of the following conditions are met:
             // *   PartialViewContext.isPartialRequest() returns true and we have a request to process all components
             // in the view (PartialViewContext.isExecuteAll() returns true)
             // *   PartialViewContext.isPartialRequest() returns false
             else
             {
                 root._processDecodesDefault(context);
             }
         }
     }
 
     private static class ProcessValidatorPhaseProcessor implements PhaseProcessor
     {
         public void process(FacesContext context, UIViewRoot root)
         {
             PartialViewContext pvc = context.getPartialViewContext();
             // Perform partial processing by calling PartialViewContext.processPartial(javax.faces.event.PhaseId)
             // with PhaseId.UPDATE_MODEL_VALUES if:
             // PartialViewContext.isPartialRequest() returns true and we don't have a request to process all components
             // in the view (PartialViewContext.isExecuteAll() returns false)
             //section 13.4.2 from the  JSF2  spec also see https://issues.apache.org/jira/browse/MYFACES-2119
             if (pvc.isPartialRequest() && !pvc.isExecuteAll())
             {
                 pvc.processPartial(PhaseId.PROCESS_VALIDATIONS);
             }
             // Perform full processing by calling UIComponentBase.processUpdates(javax.faces.context.FacesContext)
             // if one of the following conditions are met:
             // *   PartialViewContext.isPartialRequest() returns true and we have a request to process all components
             // in the view (PartialViewContext.isExecuteAll() returns true)
             // *   PartialViewContext.isPartialRequest() returns false
             else
             {
                 root._processValidatorsDefault(context);
             }
         }
     }
 
     private static class UpdateModelPhaseProcessor implements PhaseProcessor
     {
         public void process(FacesContext context, UIViewRoot root)
         {
             PartialViewContext pvc = context.getPartialViewContext();
             // Perform partial processing by calling PartialViewContext.processPartial(javax.faces.event.PhaseId)
             // with PhaseId.UPDATE_MODEL_VALUES if:
             //   * PartialViewContext.isPartialRequest() returns true and we don't have a request to process
             // all components in the view (PartialViewContext.isExecuteAll() returns false)
             //section 13.4.2 from the JSF2 spec also see https://issues.apache.org/jira/browse/MYFACES-2119
             if (pvc.isPartialRequest() && !pvc.isExecuteAll())
             {
                 pvc.processPartial(PhaseId.UPDATE_MODEL_VALUES);
             }
             // Perform full processing by calling UIComponentBase.processUpdates(javax.faces.context.FacesContext)
             // if one of the following conditions are met:
             // *   PartialViewContext.isPartialRequest() returns true and we have a request to process all components
             // in the view (PartialViewContext.isExecuteAll() returns true)
             // *   PartialViewContext.isPartialRequest() returns false
             else
             {
                 root._processUpdatesDefault(context);
             }
         }
     }
 
 /*
     private static class RestoreStateCallback implements VisitCallback
     {
         private PostRestoreStateEvent event;
 
         public VisitResult visit(VisitContext context, UIComponent target)
         {
             if (event == null)
             {
                 event = new PostRestoreStateEvent(target);
             }
             else
             {
                 event.setComponent(target);
             }
 
             // call the processEvent method of the current component.
             // The argument event must be an instance of AfterRestoreStateEvent whose component
             // property is the current component in the traversal.
             target.processEvent(event);
             
             return VisitResult.ACCEPT;
         }
     }
 */
 
     // we cannot make this class a inner class, because the 
     // enclosing class (UIViewRoot) would also have to be serialized.
     private static class ViewScope extends HashMap<String, Object>
     {
         
         private static final long serialVersionUID = -1088893802269478164L;
         
         @Override
         public void clear()
         {
             /*
              * The returned Map must be implemented such that calling clear() on the Map causes
              * Application.publishEvent(java.lang.Class, java.lang.Object) to be called, passing
              * ViewMapDestroyedEvent.class as the first argument and this UIViewRoot instance as the second argument.
              */
             FacesContext facesContext = FacesContext.getCurrentInstance();
             facesContext.getApplication().publishEvent(facesContext, 
                     PreDestroyViewMapEvent.class, facesContext.getViewRoot());
             
             super.clear();
         }
         
     }
 
     /**
      * Agregates events for ANY_PHASE and current phase 
      */
     private class Events
     {
         
         private final List<FacesEvent> _anyPhase;
         
         private final List<FacesEvent> _onPhase;
         
         public Events(List<FacesEvent> anyPhase, List<FacesEvent> onPhase)
         {
             super();
             this._anyPhase = anyPhase;
             this._onPhase = onPhase;
         }
 
         public boolean hasMoreEvents()
         {
             return (_anyPhase != null && _anyPhase.size() > 0) || (_onPhase != null && _onPhase.size() > 0); 
         }
 
         public List<FacesEvent> getAnyPhase()
         {
             return _anyPhase;
         }
 
         public List<FacesEvent> getOnPhase()
         {
             return _onPhase;
         }
     }
 }