/*
    * 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.component;
  
  import javax.el.ELException;
  import javax.el.MethodExpression;
  import javax.faces.component.StateHolder;
  import javax.faces.context.FacesContext;
  import javax.faces.el.EvaluationException;
  import javax.faces.el.MethodBinding;
  import javax.faces.el.MethodNotFoundException;
  
  /**
   * Converts a MethodExpression to a MethodBinding.  
   * See JSF 1.2 spec section 5.8.4
   *
   * ATTENTION: If you make changes to this class, treat 
   * org.apache.myfaces.el.convert.MethodExpressionToMethodBinding
   * accordingly.
   * 
   * This class could be moved or changed in the future
   * 
   * @since 1.1.7
   * @author Stan Silvert
   * @see org.apache.myfaces.el.convert.MethodExpressionToMethodBinding
   */
  public class MethodExpressionToMethodBinding extends MethodBinding implements StateHolder {
      
      private MethodExpression methodExpression;
      
      private boolean isTransient = false;
      
      public MethodExpressionToMethodBinding() {
          methodExpression = null;
      }
  
      /** Creates a new instance of MethodExpressionToMethodBinding */
      public MethodExpressionToMethodBinding(MethodExpression methodExpression) {
          this.methodExpression = methodExpression;
      }
      
      @Override
      public String getExpressionString()
      {
          return methodExpression.getExpressionString();
      }
  
      public Class getType(FacesContext facesContext) 
          throws MethodNotFoundException {
          
          try {
              return methodExpression.getMethodInfo(facesContext.getELContext()).getReturnType();
          } catch (javax.el.MethodNotFoundException e) {
              throw new javax.faces.el.MethodNotFoundException(e);
          } catch (ELException e) {
              throw new EvaluationException(e);
          }
      }
  
      public Object invoke(FacesContext facesContext, Object[] params) 
          throws EvaluationException, MethodNotFoundException {
          
          try {
              return methodExpression.invoke(facesContext.getELContext(), params);
          } catch (javax.el.MethodNotFoundException e) {
              throw new javax.faces.el.MethodNotFoundException(e);
          } catch (ELException e) {
              throw new EvaluationException(e);
          }
      }
  
  // -------- StateHolder methods -------------------------------------------    
      
      public void restoreState(FacesContext context, Object state) {
          if(state != null)
              methodExpression = (MethodExpression)state;
      }
  
      public Object saveState(FacesContext context) {
          if(!isTransient)
              return methodExpression;
          return null;
      }
 
     public void setTransient(boolean newTransientValue) {
         isTransient = newTransientValue;
     }
 
     public boolean isTransient() {
         return isTransient;
     }
     
 }