package org.apache.commons.beanutils2;
   
   /*
    * 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.
   */
  
  import static org.apache.commons.beanutils2.Argument.getParameterTypes;
  import static org.apache.commons.beanutils2.Assertions.checkNoneIsNull;
  import static org.apache.commons.beanutils2.Assertions.checkNotNull;
  
  import static java.lang.reflect.Modifier.isAbstract;
  
  import java.lang.reflect.Constructor;
  import java.lang.reflect.InvocationTargetException;
  
  final class DefaultClassAccessor<B>
      implements ClassAccessor<B>
  {
  
      private final AccessibleObjectsRegistry<Constructor<?>> constructorRegistry =
                      AccessibleObjectsRegistry.getConstructorsRegistry();
  
      private final BeanProperties<B> beanProperties;
  
      private final Class<B> beanClass;
  
      public DefaultClassAccessor( Class<B> beanClass )
      {
          this.beanClass = beanClass;
          beanProperties = new DefaultBeanProperties<B>( beanClass );
      }
  
      // pure new class instantiation
  
      /**
       * {@inheritDoc}
       */
      public BeanAccessor<B> newInstance()
      {
          return invokeConstructor();
      }
  
      // constructors
  
      /**
       * {@inheritDoc}
       */
      public BeanAccessor<B> invokeConstructor( Argument<?>... arguments )
      {
          arguments = checkNotNull( arguments,
                                    "Null arguments not admitted - don't pass any argument to use %s empty constructor",
                                    beanClass );
          arguments = checkNoneIsNull( arguments );
          return invokeConstructor( false, arguments );
      }
  
      /**
       * {@inheritDoc}
       */
      public BeanAccessor<B> invokeExactConstructor( Argument<?>... arguments )
      {
          arguments = checkNotNull( arguments,
                                    "Null arguments not admitted - don't pass any argument to use %s empty constructor",
                                    beanClass );
          arguments = checkNoneIsNull( arguments );
          return invokeConstructor( true, arguments );
      }
  
      private BeanAccessor<B> invokeConstructor( boolean exact, Argument<?>... arguments )
      {
          checkInstantiable();
          @SuppressWarnings( "unchecked" ) // type driven by beanClass
          Constructor<B> constructor = (Constructor<B>) constructorRegistry.get( exact,
                                                                                 beanClass,
                                                                                 getParameterTypes( arguments ) );
  
          if ( null == constructor )
          {
              throw new NoSuchConstructorException( beanClass, null );
          }
  
          int argumentsLength = arguments.length;
          Object[] parameterObjects = new Object[argumentsLength];
          for ( int i = 0; i < argumentsLength; i++ )
         {
             parameterObjects[i] = arguments[i].getValue();
         }
 
         B bean = doInvokeConstructor( constructor, parameterObjects );
         return new DefaultBeanAccessor<B>( bean );
     }
 
     /**
      * Checks if {@code beanClass} is instantiable and throws a {@link BeanInstantiationException} with an appropriate
      * message otherwise.
      */
     private void checkInstantiable()
     {
         if ( beanClass.isInterface() )
         {
             throw new BeanInstantiationException( beanClass, "Type is an interface." );
         }
         if ( beanClass.isArray() )
         {
             throw new BeanInstantiationException( beanClass, "Type is an array class." );
         }
         if ( beanClass.isPrimitive() )
         {
             throw new BeanInstantiationException( beanClass, "Type is primitive." );
         }
         if ( beanClass.equals( Void.TYPE ) )
         {
             throw new BeanInstantiationException( beanClass, "Type represents void." );
         }
         // has to be the last check because primitives and array types are also abstract
         if ( isAbstract( beanClass.getModifiers() ) )
         {
             throw new BeanInstantiationException( beanClass, "Type is abstract." );
         }
     }
 
     private B doInvokeConstructor( Constructor<B> constructor, Object[] parameterObjects )
     {
         try
         {
             return constructor.newInstance( parameterObjects );
         }
         catch ( InstantiationException e )
         {
             throw new BeanInstantiationException( beanClass, e );
         }
         catch ( IllegalAccessException e )
         {
             throw new ConstructorNotAccessibleException( beanClass, e );
         }
         catch ( InvocationTargetException e )
         {
             throw new ConstructorInvocationException( beanClass, e );
         }
     }
 
     // bean properties
 
     public BeanProperties<B> getProperties()
     {
         return beanProperties;
     }
 
     // static methods
 
     /**
      * {@inheritDoc}
      */
     public ArgumentsAccessor invokeStatic( String methodName )
     {
         methodName = checkNotNull( methodName, "Impossible to execute null static method in %s", beanClass );
         return new DefaultArgumentsAccessor( beanClass, false, methodName, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public ArgumentsAccessor invokeExactStatic( String methodName )
     {
         methodName = checkNotNull( methodName, "Impossible to execute null static method in %s", beanClass );
         return new DefaultArgumentsAccessor( beanClass, true, methodName, null );
     }
 
 }