/*
    * 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 javax.faces.FacesException;
  import javax.faces.component.StateHolder;
  import javax.faces.context.FacesContext;
  import javax.faces.el.EvaluationException;
  import javax.faces.el.MethodBinding;
  import javax.faces.event.AbortProcessingException;
  import javax.faces.event.FacesEvent;
  
  /**
   * Common base class for converting a MethodBinding to a FacesListener
   *
   * @author Stan Silvert
   */
  abstract class _MethodBindingToListener implements StateHolder {
      
      protected MethodBinding methodBinding;
      
      public _MethodBindingToListener() {
      }
      
      /**
       * Creates a new instance of MethodBindingToListener
       */
      public _MethodBindingToListener(MethodBinding methodBinding) {
          if (methodBinding == null) throw new NullPointerException("methodBinding can not be null");
          if (!(methodBinding instanceof StateHolder)) throw new IllegalArgumentException("methodBinding must implement the StateHolder interface");
          
          this.methodBinding = methodBinding;
      }
  
      private FacesContext getFacesContext() {
          return FacesContext.getCurrentInstance();
      }
  
      protected void invokeMethodBinding(FacesEvent event) throws AbortProcessingException {
          try {
              methodBinding.invoke(getFacesContext(), new Object[] {event});
          }
          catch (EvaluationException e) {
              Throwable cause = e.getCause();
              if (cause != null && cause instanceof AbortProcessingException) {
                  throw (AbortProcessingException)cause;
              }
              
              throw e;
          }
      }
      
      public MethodBinding getMethodBinding() {
          return methodBinding;
      }
      
      public void restoreState(FacesContext context, Object state) {
          Object[] stateArray = (Object[])state;
          try {
              methodBinding = (MethodBinding)Thread.currentThread()
                                                   .getContextClassLoader()
                                                   .loadClass((String)stateArray[0])
                                                   .newInstance();
          } catch (Exception e) {
              throw new FacesException(e);
          }
         
          ((StateHolder)methodBinding).restoreState(context, stateArray[1]);
      }
  
      public Object saveState(FacesContext context) {
          Object[] stateArray = new Object[2];
          stateArray[0] = methodBinding.getClass().getName();
          stateArray[1] = ((StateHolder)methodBinding).saveState(context);
          return stateArray;
      }
  
      public void setTransient(boolean newTransientValue) {
          ((StateHolder)methodBinding).setTransient(newTransientValue);
      }
  
      public boolean isTransient() {
         return ((StateHolder)methodBinding).isTransient();
     }
     
 }