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    1   /*
    2    * Licensed to the Apache Software Foundation (ASF) under one
    3    * or more contributor license agreements.  See the NOTICE file
    4    * distributed with this work for additional information
    5    * regarding copyright ownership.  The ASF licenses this file
    6    * to you under the Apache License, Version 2.0 (the
    7    * "License"); you may not use this file except in compliance
    8    * with the License.  You may obtain a copy of the License at
    9    *
    10   *   http://www.apache.org/licenses/LICENSE-2.0
    11   *
    12   * Unless required by applicable law or agreed to in writing,
    13   * software distributed under the License is distributed on an
    14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    15   * KIND, either express or implied.  See the License for the
    16   * specific language governing permissions and limitations
    17   * under the License.
    18   */
    19
    20  package org.apache.myfaces.shared_orchestra.util;
    21
    22  import org.apache.commons.logging.Log;
    23  import org.apache.commons.logging.LogFactory;
    24
    25  import javax.faces.context.FacesContext;
    26  import javax.faces.component.UIComponent;
    27  import javax.faces.component.UIInput;
    28  import javax.faces.el.ValueBinding;
    29  import java.util.Iterator;
    30  import java.lang.reflect.Method;
    31
    32  /**
    33   * @author Martin Marinschek (latest modification by $Author: grantsmith $)
    34   * @version $Revision: 169655 $ $Date: 2005-05-11 18:45:06 +0200 (Mi, 11 Mai 2005) $
    35   */
    36  public class RestoreStateUtils
    37  {
    38      private static Log log = LogFactory.getLog(RestoreStateUtils.class);
    39
    40      /**
    41       * Walk the component tree, executing any component-bindings to reattach
    42       * components to their backing beans. Also, any UIInput component is
    43       * marked as Valid.
    44       * <p>
    45       *  Note that this method effectively breaks encapsulation; instead of
    46       *  asking each component to update itself and its children, this
    47       * method just reaches into each component. That makes it impossible
    48       * for any component to customise its behaviour at this point.
    49       * <p>
    50       * This has been filed as an issue against the spec. Until this
    51       * issue is resolved, we'll add a new marker-interface for components
    52       * to allow them to define their interest in handling children bindings themselves.
    53       */
    54      public static void recursivelyHandleComponentReferencesAndSetValid(FacesContext facesContext,
    55                                                                         UIComponent parent)
    56      {
    57          recursivelyHandleComponentReferencesAndSetValid(facesContext, parent, false);
    58      }
    59
    60      public static void recursivelyHandleComponentReferencesAndSetValid(FacesContext facesContext,
    61                                                                         UIComponent parent, boolean forceHandle)
    62      {
    63          Method handleBindingsMethod = getBindingMethod(parent);
    64
    65          if(handleBindingsMethod!=null && !forceHandle)
    66          {
    67              try
    68              {
    69                  handleBindingsMethod.invoke(parent,new Object[]{});
    70              }
    71              catch (Throwable th)
    72              {
    73                  log.error("Exception while invoking handleBindings on component with client-id:"
    74                          +parent.getClientId(facesContext),th);
    75              }
    76          }
    77          else
    78          {
    79              for (Iterator it = parent.getFacetsAndChildren(); it.hasNext(); )
    80              {
    81                  UIComponent component = (UIComponent)it.next();
    82
    83                  ValueBinding binding = component.getValueBinding("binding");    //TODO: constant
    84                  if (binding != null && !binding.isReadOnly(facesContext))
    85                  {
    86                      binding.setValue(facesContext, component);
    87                  }
    88
    89                  if (component instanceof UIInput)
    90                  {
    91                      ((UIInput)component).setValid(true);
    92                  }
    93
    94                  recursivelyHandleComponentReferencesAndSetValid(facesContext, component);
    95              }
    96          }
    97      }
    98
    99      /**This is all a hack to work around a spec-bug which will be fixed in JSF2.0
    100      *
    101      * @param parent
    102      * @return true if this component is bindingAware (e.g. aliasBean)
    103      */
    104     private static Method getBindingMethod(UIComponent parent)
    105     {
    106         Class[] clazzes = parent.getClass().getInterfaces();
    107
    108         for (int i = 0; i < clazzes.length; i++)
    109         {
    110             Class clazz = clazzes[i];
    111
    112             if(clazz.getName().indexOf("BindingAware")!=-1)
    113             {
    114                 try
    115                 {
    116                     return  parent.getClass().getMethod("handleBindings",new Class[]{});
    117                 }
    118                 catch (NoSuchMethodException e)
    119                 {
    120                     // return
    121                 }
    122             }
    123         }
    124
    125         return null;
    126     }
    127 }