/*

  * 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.view;

 import java.util.Collection;

 import java.util.Collections;

 import java.util.Iterator;

 import java.util.LinkedList;

 import javax.faces.component.UIComponent;

 import javax.faces.component.UIViewParameter;

 import javax.faces.component.UIViewRoot;

 import javax.faces.context.FacesContext;

 /**

  * @author Simon Lessard (latest modification by $Author: slessard $)

  * @version $Revision: 696523 $ $Date: 2009-03-14 20:10:08 -0400 (mer., 17 sept. 2008) $

  *

  * @since 2.0

  */

 public abstract class ViewMetadata

 {

     public abstract UIViewRoot createMetadataView(FacesContext context);

     public abstract String getViewId();

     public static Collection<UIViewParameter> getViewParameters(UIViewRoot root)

     {

         LinkedList<UIViewParameter> result = new LinkedList<UIViewParameter>();

         UIComponent metadataFacet = root.getFacet (UIViewRoot.METADATA_FACET_NAME);

         Iterator<UIComponent> children;

         if (metadataFacet == null) {

              // No metadata, so return an empty collection.

              return Collections.emptyList();

         }

         // Iterate over all the children, keep only the view parameters.

         children = metadataFacet.getChildren().iterator();

         while (children.hasNext()) {

              UIComponent component = children.next();

              if (component instanceof UIViewParameter) {

                   result.add ((UIViewParameter) component);

              }

         }

         // TODO: does this need to be immutable?  Spec does not indicate either

         // way.

         return Collections.unmodifiableCollection (result);

     }

 }