xstream对xmlnode的属性(attribute)解析的问题[更新]。
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 >
< 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
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);
<
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。
< photos >
< photo id ="ff8080810fc8ac78010fd3f158d40a52"
owner ="ff8080810f1a387b010f1a83d6530dfc" title ="Gmail-2" host ="4"
dir ="20061230" filename ="231905_1463411198" />
</ photos >
</ result >
Hello, I am not sure about the subject but here is what I needed help for: XML: <field name="value">I am a Field.</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 <a href="mailto:[email protected]">somebody</a>
* @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 );
参考:
http://xstream.codehaus.org/converter-tutorial.html
2007年1月18日更新。
这里感谢网友 Ivan Chen（西滨） 的提示。原来新版的xstream可以简单的解决了。在1.2.1的doc里面找到了这个两个方法。
useAttributeFor
public void useAttributeFor(java.lang.String fieldName,
java.lang.Class type)
- Use an XML attribute for a field or a specific type.
-
- Parameters:
-
fieldName- the name of the field -
type- the Class of the type to be rendered as XML attribute - Throws:
-
XStream.InitializationException- if noAttributeMapperis available - Since:
- 1.2
useAttributeFor
public void useAttributeFor(java.lang.Class type)
- Use an XML attribute for an arbotrary type.
-
- Parameters:
-
type- the Class of the type to be rendered as XML attribute - Throws:
-
XStream.InitializationException- if noAttributeMapperis available - Since:
- 1.2
这两个方法都是从1.2开始支持的。
也不用自己写converter了。这样就可以了
stream.alias(
"
result
"
, YupooResult.
class
);
stream.useAttributeFor( " page " , Integer. class );
stream.useAttributeFor( " pages " , Integer. class );
stream.useAttributeFor( " perpage " , Integer. class );
stream.useAttributeFor( " total " , Integer. class );
stream.alias( " photo " , YupooPhoto. class );
stream.useAttributeFor( " id " , String. class );
stream.useAttributeFor( " owner " , String. class );
stream.useAttributeFor( " title " , String. class );
stream.useAttributeFor( " host " , String. class );
stream.useAttributeFor( " dir " , String. class );
stream.useAttributeFor( " filename " , String. class );
stream.useAttributeFor( " page " , Integer. class );
stream.useAttributeFor( " pages " , Integer. class );
stream.useAttributeFor( " perpage " , Integer. class );
stream.useAttributeFor( " total " , Integer. class );
stream.alias( " photo " , YupooPhoto. class );
stream.useAttributeFor( " id " , String. class );
stream.useAttributeFor( " owner " , String. class );
stream.useAttributeFor( " title " , String. class );
stream.useAttributeFor( " host " , String. class );
stream.useAttributeFor( " dir " , String. class );
stream.useAttributeFor( " filename " , String. class );
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)