package org.apache.commons.ognl;

 /*

  * 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 java.util.Enumeration;

 import java.util.Map;

 /**

  * Implementation of PropertyAccessor that provides "property" reference to "nextElement" (aliases to "next" also) and

  * "hasMoreElements" (also aliased to "hasNext").

  * 

  * @author Luke Blanshard (blanshlu@netscape.net)

  * @author Drew Davidson (drew@ognl.org)

  */

 public class EnumerationPropertyAccessor

     extends ObjectPropertyAccessor

     implements PropertyAccessor // This is here to make javadoc show this class as an implementor

 {

     @Override

     public Object getProperty( Map<String, Object> context, Object target, Object name )

         throws OgnlException

     {

         Object result;

         Enumeration<?> e = (Enumeration<?>) target; // check performed by the invoker

         if ( name instanceof String )

         {

             if ( "next".equals( name ) || "nextElement".equals( name ) )

             {

                 result = e.nextElement();

             }

             else

             {

                 if ( "hasNext".equals( name ) || "hasMoreElements".equals( name ) )

                 {

                     result = e.hasMoreElements() ? Boolean.TRUE : Boolean.FALSE;

                 }

                 else

                 {

                     result = super.getProperty( context, target, name );

                 }

             }

         }

         else

         {

             result = super.getProperty( context, target, name );

         }

         return result;

     }

     @Override

     public void setProperty( Map<String, Object> context, Object target, Object name, Object value )

         throws OgnlException

     {

         throw new IllegalArgumentException( "can't set property " + name + " on Enumeration" );

     }

 }