2009/05/20 - Apache Shale has been retired.

   /*
    * 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.shale.test.el;
  
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  
  import javax.el.ELContext;
  import javax.el.PropertyNotFoundException;
  import javax.el.PropertyNotWritableException;
  import javax.faces.component.UIViewRoot;
  import javax.faces.context.ExternalContext;
  import javax.faces.context.FacesContext;
  
  /***
   * <p><code>ELResolver</code> implementation that accesses implicit objects
   * in the current request context.  See the JSF 1.2 Specification, section
   * 5.6.2.1, for requirements implemented by this class.</p>
   *
   * @since 1.0.4
   */
  public class FacesImplicitObjectELResolver extends AbstractELResolver {
      
  
      /***
       * <p>The names of all implicit objects recognized by this resolver.</p>
       */
      private static final String[] NAMES =
      { "application", "applicationScope", "cookie", "facesContext",
        "header", "headerValues", "initParam", "param", "paramValues",
        "request", "requestScope", "session", "sessionScope", "view" };
  
  
      /***
       * <p>The property types corresponding to the implicit object names.</p>
       */
      private static final Class[] TYPES =
      { Object.class, Map.class, Map.class, FacesContext.class,
        Map.class, Map.class, Map.class, Map.class, Map.class,
        Object.class, Map.class, Object.class, Map.class, UIViewRoot.class };
  
  
      /***
       * <p>The settable value types corresponding to the implicit
       * object names.</p>
       */
      private static final Class[] VALUES =
      { null, Object.class, null, null,
        null, null, null, null, null,
        null, Object.class, null, Object.class, null };
  
  
      /***
       * <p>Return the most general type this resolver accepts for the
       * <code>property</code> argument.</p>
       */
      public Class getCommonPropertyType(ELContext context, Object base) {
  
          if (base != null) {
              return null;
          } else {
              return String.class;
          }
  
      }
  
  
      /***
       * <p>Return an <code>Iterator</code> over the attributes that this
       * resolver knows how to deal with.</p>
       *
       * @param context <code>ELContext</code> for evaluating this value
       * @param base Base object against which this evaluation occurs
       */
      public Iterator getFeatureDescriptors(ELContext context, Object base) {
  
          if (base != null) {
              return null;
          }
  
          // Create the variables we will need
          FacesContext fcontext = (FacesContext) context.getContext(FacesContext.class);
         List descriptors = new ArrayList();
 
         // Add feature descriptors for each implicit object
         for (int i = 0; i < NAMES.length; i++) {
             descriptors.add(descriptor(NAMES[i], NAMES[i], NAMES[i],
                                    false, false, true, TYPES[i], true));
         }
 
         // Return the accumulated descriptors
         return descriptors.iterator();
 
     }
 
 
 
     /***
      * <p>Return the Java type of the specified property.</p>
      *
      * @param context <code>ELContext</code> for evaluating this value
      * @param base Base object against which this evaluation occurs
      *  (must be null because we are evaluating a top level variable)
      * @param property Property name to be accessed
      */
     public Class getType(ELContext context, Object base, Object property) {
 
         if (base != null) {
             return null;
         }
         if (property == null) {
             throw new PropertyNotFoundException("No property specified");
         }
         String name = property.toString();
         for (int i = 0; i < NAMES.length; i++) {
             if (name.equals(NAMES[i])) {
                 context.setPropertyResolved(true);
                 return VALUES[i];
             }
         }
         return null;
 
     }
 
 
     /***
      * <p>Return an existing scoped object for the specified name (if any);
      * otherwise, return <code>null</code>.</p>
      *
      * @param context <code>ELContext</code> for evaluating this value
      * @param base Base object against which this evaluation occurs
      *  (must be null because we are evaluating a top level variable)
      * @param property Property name to be accessed
      */
     public Object getValue(ELContext context, Object base, Object property) {
 
         if (base != null) {
             return null;
         }
         if (property == null) {
             throw new PropertyNotFoundException("No property specified");
         }
 
         FacesContext fcontext = (FacesContext) context.getContext(FacesContext.class);
         ExternalContext econtext = fcontext.getExternalContext();
         String name = property.toString();
 
         if (name.equals("application")) {
             context.setPropertyResolved(true);
             return econtext.getContext();
         } else if (name.equals("applicationScope")) {
             context.setPropertyResolved(true);
             return econtext.getApplicationMap();
         } else if (name.equals("cookie")) {
             context.setPropertyResolved(true);
             return econtext.getRequestCookieMap();
         } else if (name.equals("facesContext")) {
             context.setPropertyResolved(true);
             return fcontext;
         } else if (name.equals("header")) {
             context.setPropertyResolved(true);
             return econtext.getRequestHeaderMap();
         } else if (name.equals("headerValues")) {
             context.setPropertyResolved(true);
             return econtext.getRequestHeaderValuesMap();
         } else if (name.equals("initParam")) {
             context.setPropertyResolved(true);
             return econtext.getInitParameterMap();
         } else if (name.equals("param")) {
             context.setPropertyResolved(true);
             return econtext.getRequestParameterMap();
         } else if (name.equals("paramValues")) {
             context.setPropertyResolved(true);
             return econtext.getRequestParameterValuesMap();
         } else if (name.equals("request")) {
             context.setPropertyResolved(true);
             return econtext.getRequest();
         } else if (name.equals("requestScope")) {
             context.setPropertyResolved(true);
             return econtext.getRequestMap();
         } else if (name.equals("session")) {
             context.setPropertyResolved(true);
             return econtext.getSession(true);
         } else if (name.equals("sessionScope")) {
             context.setPropertyResolved(true);
             return econtext.getSessionMap();
         } else if (name.equals("view")) {
             context.setPropertyResolved(true);
             return fcontext.getViewRoot();
         }
 
         return null;
 
     }
 
 
     /***
      * <p>Return <code>true</code> if the specified property is read only.</p>
      *
      * @param context <code>ELContext</code> for evaluating this value
      * @param base Base object against which this evaluation occurs
      *  (must be null because we are evaluating a top level variable)
      * @param property Property name to be accessed
      */
     public boolean isReadOnly(ELContext context, Object base, Object property) {
 
         if (base != null) {
             return false;
         }
         if (property == null) {
             throw new PropertyNotFoundException("No property specified");
         }
         String name = property.toString();
         for (int i = 0; i < NAMES.length; i++) {
             if (name.equals(NAMES[i])) {
                 context.setPropertyResolved(true);
                 return true;
             }
         }
         return false;
 
     }
 
 
 
     /***
      * <p>Set the value of a scoped object for the specified name.</p>
      *
      * @param context <code>ELContext</code> for evaluating this value
      * @param base Base object against which this evaluation occurs
      *  (must be null because we are evaluating a top level variable)
      * @param property Property name to be accessed
      * @param value New value to be set
      */
     public void setValue(ELContext context, Object base, Object property, Object value) {
 
         if (base != null) {
             return;
         }
         if (property == null) {
             throw new PropertyNotFoundException("No property specified");
         }
 
         String name = property.toString();
         for (int i = 0; i < NAMES.length; i++) {
             if (name.equals(NAMES[i])) {
                 context.setPropertyResolved(true);
                 throw new PropertyNotWritableException(name);
             }
         }
 
     }
 
 
 }