package org.apache.commons.ognl.internal.entry;
   
   /*
    * 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.
   */
  
  /*
   * $Id: GenericMethodParameterTypeFactory.java 1194956 2011-10-29 18:02:14Z mcucchiara $
   */
  
  import org.apache.commons.ognl.internal.CacheException;
  
  import java.lang.reflect.Array;
  import java.lang.reflect.GenericArrayType;
  import java.lang.reflect.ParameterizedType;
  import java.lang.reflect.Type;
  import java.lang.reflect.TypeVariable;
  
  public class GenericMethodParameterTypeFactory
      implements CacheEntryFactory<GenericMethodParameterTypeCacheEntry, Class<?>[]>
  {
      public Class<?>[] create( GenericMethodParameterTypeCacheEntry entry )
          throws CacheException
      {
          Class<?>[] types;
  
          ParameterizedType param = (ParameterizedType) entry.type.getGenericSuperclass();
          Type[] genTypes = entry.method.getGenericParameterTypes();
          TypeVariable<?>[] declaredTypes = entry.method.getDeclaringClass().getTypeParameters();
  
          types = new Class[genTypes.length];
  
          for ( int i = 0; i < genTypes.length; i++ )
          {
              TypeVariable<?> paramType = null;
  
              if ( TypeVariable.class.isInstance( genTypes[i] ) )
              {
                  paramType = (TypeVariable<?>) genTypes[i];
              }
              else if ( GenericArrayType.class.isInstance( genTypes[i] ) )
              {
                  paramType = (TypeVariable<?>) ( (GenericArrayType) genTypes[i] ).getGenericComponentType();
              }
              else if ( ParameterizedType.class.isInstance( genTypes[i] ) )
              {
                  types[i] = (Class<?>) ( (ParameterizedType) genTypes[i] ).getRawType();
                  continue;
              }
              else if ( Class.class.isInstance( genTypes[i] ) )
              {
                  types[i] = (Class<?>) genTypes[i];
                  continue;
              }
  
              Class<?> resolved = resolveType( param, paramType, declaredTypes );
  
              if ( resolved != null )
              {
                  if ( GenericArrayType.class.isInstance( genTypes[i] ) )
                  {
                      resolved = Array.newInstance( resolved, 0 ).getClass();
                  }
  
                  types[i] = resolved;
                  continue;
              }
              types[i] = entry.method.getParameterTypes()[i];
          }
  
          return types;
      }
  
      private Class<?> resolveType( ParameterizedType param, TypeVariable<?> var, TypeVariable<?>[] declaredTypes )
      {
          if ( param.getActualTypeArguments().length < 1 )
          {
              return null;
          }
  
          for ( int i = 0; i < declaredTypes.length; i++ )
          {
              if ( !TypeVariable.class.isInstance( param.getActualTypeArguments()[i] )
                  && declaredTypes[i].getName().equals( var.getName() ) )
             {
                 return (Class<?>) param.getActualTypeArguments()[i];
             }
         }
 
         return null;
     }
 }