/*

  * 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.lifecycle;

 import javax.faces.component.UIComponent;

 import javax.faces.context.FacesContext;

 /**

  * Support class for restore view phase

  * 

  * @author Mathias Broekelmann (latest modification by $Author$)

  * @version $Revision$ $Date$

  */

 public interface RestoreViewSupport

 {

     /**

      * <p>

      * Calculates the view id from the given faces context by the following algorithm

      * </p>

      * <ul>

      * <li>lookup the viewid from the request attribute "javax.servlet.include.path_info"

      * <li>if null lookup the value for viewid by {@link javax.faces.context.ExternalContext#getRequestPathInfo()}

      * <li>if null lookup the value for viewid from the request attribute "javax.servlet.include.servlet_path"

      * <li>if null lookup the value for viewid by {@link javax.faces.context.ExternalContext#getRequestServletPath()}

      * <li>if null throw a {@link javax.faces.FacesException}

      * </ul>

      */

     String calculateViewId(FacesContext facesContext);

     /**

      *  Derive a view id retrieved from calling calculateViewId(FacesContext), but

      * do not check if a resource with this name exists. This method is useful

      * to retrieve a VDL instance, but note there are some cases (TCK test) where

      * it is expected in Restore View algorithm a null or dummy viewId is passed. 

      * 

      * @deprecated Use ViewHandler.deriveLogicalViewId

      * @param context

      * @param viewId

      * @return

      */

     @Deprecated

     String deriveViewId(FacesContext context, String viewId);

     /**

      * Processes the component tree. For each component (including the given one) in the tree determine if a value

      * expression for the attribute "binding" is defined. If the expression is not null set the component instance to

      * the value of this expression

      * 

      * @param facesContext

      * @param component

      *            the root component

      */

     void processComponentBinding(FacesContext facesContext, UIComponent component);

     /**

      * <p>

      * Determine if the current request is a post back by the following algorithm.

      * </p>

      * <p>

      * Find the render-kit-id for the current request by calling calculateRenderKitId() on the Application’s

      * ViewHandler. Get that RenderKit’s ResponseStateManager and call its isPostback() method, passing the given

      * FacesContext.

      * </p>

      * 

      * @param facesContext

      * @return

      */

     boolean isPostback(FacesContext facesContext);

     /**

      * Check if a view exists

      * 

      * @param facesContext

      * @param viewId

      * @return 

      */

     boolean checkViewExists(FacesContext facesContext, String viewId);

 }