xstream对xmlnode的属性(attribute)解析的问题。

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xstream是个好东西。对于配置文件的读取很方便。在mybog中我就用到了。不过今天打算用yupoo的api来做相册。发现xstream对于xmlnode的attribute解析支持不是那么的好。
对于这种节点格式的非常的简单

< result >
     < page > 1 page >
     < pages > 1 pages >
     < perpage > 100 perpage >
     < total > 19 total >
     < photos >
         < photo >
             < id > ff8080810fc8ac78010fd3f158d40a52 id >
             < owner > ff8080810f1a387b010f1a83d6530dfc owner >
             < title > Gmail-2 title >
             < host > 4 host >
             < dir > 20061230 dir >
             < filename > 231905_1463411198 filename >
         photo >
     photos >
result >

简单的alias一下就可以读到值了

File file  =   new  File( " src/test/java/com/jdkcn/test/result.xml " );
BufferedReader reader  =   new  BufferedReader( new  InputStreamReader( new  FileInputStream(file),  " UTF-8 " ));
XStream stream  =   new  XStream();
stream.alias( " result " , YupooResult. class );
stream.alias( " photo " ,YupooPhoto. class );
YupooResult result  =  (YupooResult)stream.fromXML(reader);

可是Yupoo的api返回的xmlrpc的结果是这样的

< result  page ="1"  pages ="1"  perpage ="100"  total ="19" >
     < photos >
         < photo  id ="ff8080810fc8ac78010fd3f158d40a52"
            owner ="ff8080810f1a387b010f1a83d6530dfc"  title ="Gmail-2"  host ="4"
            dir ="20061230"  filename ="231905_1463411198"   />
     photos >
result >

这样就load不到值了。没法去mailist里面找答案，果然有人问。

Hello,

I am not sure about the subject but here is what I needed help for:

XML:

I am a Field.

I have already tried several structures and nothing seem to work.

Is this possible for XStream? :)

How is the Java class form to support this?

Thanks!




有人回答是看Converter的文档。果然找到答案了。
自己写一个converter就可以了。
下面是我的converter

  
  
  
  

   
   
   
   package
   
   
   
    com.jdkcn.xstream;


   
   
   
   import
   
   
   
    java.util.ArrayList;

   
   
   
   import
   
   
   
    java.util.List;


   
   
   
   import
   
   
   
    com.jdkcn.yupoo.YupooPhoto;

   
   
   
   import
   
   
   
    com.jdkcn.yupoo.YupooResult;

   
   
   
   import
   
   
   
    com.thoughtworks.xstream.converters.Converter;

   
   
   
   import
   
   
   
    com.thoughtworks.xstream.converters.MarshallingContext;

   
   
   
   import
   
   
   
    com.thoughtworks.xstream.converters.UnmarshallingContext;

   
   
   
   import
   
   
   
    com.thoughtworks.xstream.io.HierarchicalStreamReader;

   
   
   
   import
   
   
   
    com.thoughtworks.xstream.io.HierarchicalStreamWriter;


   
   
   
   /**
   
   
   
   
 * 
   
   
   
   @author
   
   
   
    somebody
 * 
   
   
   
   @since
   
   
   
    Jan 16, 2007 6:12:35 PM
 * 
   
   
   
   @version
   
   
   
    $Id YupooResultConverter.java$
 
   
   
   
   */
   
   
   
   

   
   
   
   public
   
   
   
    
   
   
   
   class
   
   
   
    YupooResultConverter 
   
   
   
   implements
   
   
   
    Converter {
    
   
   
   
   /*
   
   
   
    (non-Javadoc)
     * @see com.thoughtworks.xstream.converters.Converter#marshal(java.lang.Object, com.thoughtworks.xstream.io.HierarchicalStreamWriter, com.thoughtworks.xstream.converters.MarshallingContext)
     
   
   
   
   */
   
   
   
   
    
   
   
   
   public
   
   
   
    
   
   
   
   void
   
   
   
    marshal(Object obj, HierarchicalStreamWriter writer, MarshallingContext context) {
        
   
   
   
   //
   
   
   
    FIXME unfinish.
   
   
   
   

   
   
   
       }

    
   
   
   
   /*
   
   
   
    (non-Javadoc)
     * @see com.thoughtworks.xstream.converters.Converter#unmarshal(com.thoughtworks.xstream.io.HierarchicalStreamReader, com.thoughtworks.xstream.converters.UnmarshallingContext)
     
   
   
   
   */
   
   
   
   
    
   
   
   
   public
   
   
   
    Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
        YupooResult result 
   
   
   
   =
   
   
   
    
   
   
   
   new
   
   
   
    YupooResult();
        result.setPage(
   
   
   
   new
   
   
   
    Integer(reader.getAttribute(
   
   
   
   "
   
   
   
   page
   
   
   
   "
   
   
   
   )));
        result.setPages(
   
   
   
   new
   
   
   
    Integer(reader.getAttribute(
   
   
   
   "
   
   
   
   pages
   
   
   
   "
   
   
   
   )));
        result.setPerpage(
   
   
   
   new
   
   
   
    Integer(reader.getAttribute(
   
   
   
   "
   
   
   
   perpage
   
   
   
   "
   
   
   
   )));
        result.setTotal(
   
   
   
   new
   
   
   
    Integer(reader.getAttribute(
   
   
   
   "
   
   
   
   total
   
   
   
   "
   
   
   
   )));
        reader.moveDown();
        List
   
   
   
   <
   
   
   
   YupooPhoto
   
   
   
   >
   
   
   
    photos 
   
   
   
   =
   
   
   
    
   
   
   
   new
   
   
   
    ArrayList
   
   
   
   <
   
   
   
   YupooPhoto
   
   
   
   >
   
   
   
   ();
        
   
   
   
   while
   
   
   
   (reader.hasMoreChildren()) {
            reader.moveDown();
            YupooPhoto photo 
   
   
   
   =
   
   
   
    
   
   
   
   new
   
   
   
    YupooPhoto();
            photo.setDir(reader.getAttribute(
   
   
   
   "
   
   
   
   dir
   
   
   
   "
   
   
   
   ));
            photo.setFilename(reader.getAttribute(
   
   
   
   "
   
   
   
   filename
   
   
   
   "
   
   
   
   ));
            photo.setHost(reader.getAttribute(
   
   
   
   "
   
   
   
   host
   
   
   
   "
   
   
   
   ));
            photo.setId(reader.getAttribute(
   
   
   
   "
   
   
   
   id
   
   
   
   "
   
   
   
   ));
            photo.setOwner(reader.getAttribute(
   
   
   
   "
   
   
   
   owner
   
   
   
   "
   
   
   
   ));
            photo.setTitle(reader.getAttribute(
   
   
   
   "
   
   
   
   title
   
   
   
   "
   
   
   
   ));
            photos.add(photo);
            reader.moveUp();
        }
        result.setPhotos(photos);
        
   
   
   
   return
   
   
   
    result;
    }
    
   
   
   
   /*
   
   
   
    (non-Javadoc)
     * @see com.thoughtworks.xstream.converters.ConverterMatcher#canConvert(java.lang.Class)
     
   
   
   
   */
   
   
   
   
    
   
   
   
   public
   
   
   
    
   
   
   
   boolean
   
   
   
    canConvert(Class clazz) {
        
   
   
   
   return
   
   
   
    clazz.equals(YupooResult.
   
   
   
   class
   
   
   
   );
    }
}

  
  
  
  
然后调用的地方修改一下就ok了。

  
  
  
  

   
   
   
   XStream stream 
   
   
   
   =
   
   
   
    
   
   
   
   new
   
   
   
    XStream();
stream.registerConverter(
   
   
   
   new
   
   
   
    YupooResultConverter());
stream.alias(
   
   
   
   "
   
   
   
   result
   
   
   
   "
   
   
   
   , YupooResult.
   
   
   
   class
   
   
   
   );
  
  
  
  

以后大家一定要注意啊。顺序问题也是很重要的。
   除经特别注明外,本文章版权归莫多泡泡所有. 
署名,非商业用途,保持一致.   somebody(莫多)























参考:
http://xstream.codehaus.org/converter-tutorial.html

莫多 2007-01-17 18:24 发表评论