content: /*
   * Convert.java January 2010
   *
   * Copyright (C) 2010, Niall Gallagher <niallg@users.sf.net>
   *
   * Licensed 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 com.aliyun.odps.simpleframework.xml.convert;
  
  import java.lang.annotation.Retention;
  import java.lang.annotation.RetentionPolicy;
  
  /**
   * The <code>Convert</code> annotation is used to specify a converter
   * class to use for serialization. This annotation is used when an
   * object needs to be serialized but can not be annotated or when the
   * object can not conform to an existing XML structure. In order to
   * specify a <code>Converter</code> object a field or method can be
   * annotated like the field below.
   * <pre>
   * 
   *    &#64;Element
   *    &#64;Convert(ExampleConverter.class)
   *    private Example example;
   * 
   * </pre>
   * Note that for the above field the <code>Element</code> annotation
   * is required. If this is used with any other XML annotation such 
   * as the <code>ElementList</code> or <code>Text</code> annotation
   * then an exception will be thrown. As well as field and methods
   * this can be used to suggest a converter for a class. Take the 
   * class below which is annotated.
   * <pre>
   * 
   *    &#64;Root
   *    &#64;Convert(DemoConverter.class)
   *    public class Demo {
   *       ...
   *    }
   * 
   * </pre>
   * For the above class the specified converter will be used. This is
   * useful when the class is used within a <code>java.util.List</code>
   * or another similar collection. Finally, in order for this to work
   * it must be used with the <code>AnnotationStrategy</code> which is
   * used to scan for annotations in order to delegate to converters.
   * 
   * @author Niall Gallagher
   * 
   * @see AnnotationStrategy
   */
  @Retention(RetentionPolicy.RUNTIME)
  public @interface Convert {
     
     /**
      * Specifies the <code>Converter</code> implementation to be used
      * to convert the annotated object. The converter specified will
      * be used to convert the object to XML by intercepting the 
      * serialization and deserialization process as it happens. A
      * converter should typically be used to handle an object of 
      * a specific type.
      * 
      * @return this returns the converter that has been specified
      */
     Class<? extends Converter> value();
  }
  