xStream可以轻易的将Java对象和xml文档相互转换，而且可以修改某个特定的属性和节点名称，而且也支持json的转换；
前面有介绍过json-lib这个框架，在线博文：http://www.cnblogs.com/hoojo/archive/2011/04/21/2023805.html
以及Jackson这个框架，在线博文：http://www.cnblogs.com/hoojo/archive/2011/04/22/2024628.html
它们都完美支持JSON，但是对xml的支持还不是很好。一定程度上限制了对Java对象的描述，不能让xml完全体现到对Java对象的描述。这里将会介绍xStream对JSON、XML的完美支持。xStream不仅对XML的转换非常友好，而且提供annotation注解，可以在JavaBean中完成对xml节点、属性的描述。以及对JSON也支持，只需要提供相关的JSONDriver就可以完成转换。
原文地址
xStream完美转换XML、JSON
http://www.cnblogs.com/hoojo/archive/2011/04/22/2025197.html
以下是学习笔记：
1，改造成Maven工程后的pom.xml文件
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.coderdream</groupId>
<artifactId>xsteam-demo</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>xsteam-demo Maven Webapp</name>
<url>http://maven.apache.org</url>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.8.2</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.thoughtworks.xstream</groupId>
<artifactId>xstream</artifactId>
<version>1.4.8</version>
</dependency>
<dependency>
<groupId>org.codehaus.jettison</groupId>
<artifactId>jettison</artifactId>
<version>1.3.7</version>
</dependency>
</dependencies>
<build>
<finalName>xsteam-demo</finalName>
</build>
</project>
2，完整的XStreamTest.java文件：
package com.hoo.test;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.StringReader;
import java.io.Writer;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.codehaus.jettison.json.JSONException;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import com.hoo.entity.Birthday;
import com.hoo.entity.Classes;
import com.hoo.entity.Student;
import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
import com.thoughtworks.xstream.io.json.JettisonMappedXmlDriver;
import com.thoughtworks.xstream.io.json.JsonHierarchicalStreamDriver;
import com.thoughtworks.xstream.io.json.JsonWriter;
/**
* <b>function:</b>Java对象和XML字符串的相互转换 jar-lib-version: xstream-1.3.1
*
* @author hoojo
* @createDate Nov 27,2010 12:15:15 PM
* @file XStreamTest.java
* @package com.hoo.test
* @project WebHttpUtils
* @blog http://blog.csdn.net/IBM_hoojo
* @email hoojo_@126.com
* @version 1.0
*/
public class XStreamTest {
private XStream xstream = null;
private ObjectOutputStream out = null;
private ObjectInputStream in = null;
private Student bean = null;
/**
* <b>function:</b>初始化资源准备
*
* @author hoojo
* @createDate Nov 27,2010 12:16:28 PM
*/
@Before
public void init() {
try {
xstream = new XStream();
// xstream = new XStream(new DomDriver()); // 需要xpp3 jar
} catch (Exception e) {
e.printStackTrace();
}
bean = new Student();
bean.setAddress("china");
bean.setEmail("jack@email.com");
bean.setId(1);
bean.setName("jack");
Birthday day = new Birthday();
day.setBirthday("2010-11-22");
bean.setBirthday(day);
}
/**
* <b>function:</b>释放对象资源
*
* @author hoojo
* @createDate Nov 27,2010 12:16:38 PM
*/
@After
public void destory() {
xstream = null;
bean = null;
try {
if (out != null) {
out.flush();
out.close();
}
if (in != null) {
in.close();
}
} catch (IOException e) {
e.printStackTrace();
}
System.gc();
}
public final void fail(String string) {
System.out.println(string);
}
public final void failRed(String string) {
System.err.println(string);
}
@Test
public void writeList2XML4Annotation() {
try {
failRed("---------annotation Bean --> XML---------");
Student stu = new Student();
stu.setName("jack");
Classes c = new Classes("一班",bean,stu);
c.setNumber(2);
// 对指定的类使用Annotation
// xstream.processAnnotations(Classes.class);
// 启用Annotation
// xstream.autodetectAnnotations(true);
xstream.alias("student",Student.class);
fail(xstream.toXML(c));
} catch (Exception e) {
e.printStackTrace();
}
}
@Test
public void writeList2XML4Annotation2() {
try {
failRed("---------annotation Bean --> XML---------");
Student stu = new Student();
stu.setName("jack");
Classes c = new Classes("一班",stu);
c.setNumber(2);
// 对指定的类使用Annotation
xstream.processAnnotations(Classes.class);
// 启用Annotation
xstream.autodetectAnnotations(true);
xstream.alias("student",Student.class);
fail(xstream.toXML(c));
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* <b>function:</b>Java Map集合转XML
*
* @author hoojo
* @createDate Nov 27,2010 1:13:26 PM
*/
@Test
public void writeMap2XML() {
try {
failRed("---------Map --> XML---------");
Map<String,Student> map = new HashMap<String,Student>();
map.put("No.1",bean);// put
bean = new Student();
bean.setAddress("china");
bean.setEmail("tom@125.com");
bean.setId(2);
bean.setName("tom");
Birthday day = new Birthday("2010-11-22");
bean.setBirthday(day);
map.put("No.2",bean);// put
bean = new Student();
bean.setName("jack");
map.put("No.3",bean);// put
xstream.alias("student",Student.class);
xstream.alias("key",String.class);
xstream.useAttributeFor(Student.class,"id");
xstream.useAttributeFor("birthday",String.class);
fail(xstream.toXML(map));
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* <b>function:</b>用OutStream输出流写XML
*
* @author hoojo
* @createDate Nov 27,2010 1:13:48 PM
*/
@Test
public void writeXML4OutStream() {
try {
out = xstream.createObjectOutputStream(System.out);
Student stu = new Student();
stu.setName("jack");
Classes c = new Classes("一班",stu);
c.setNumber(2);
failRed("---------ObjectOutputStream # JavaObject--> XML---------");
out.writeObject(stu);
out.writeObject(new Birthday("2010-05-33"));
out.write(22);// byte
out.writeBoolean(true);
out.writeFloat(22.f);
out.writeUTF("hello");
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* <b>function:</b>用InputStream将XML文档转换成java对象 需要额外的jar xpp3-main.jar
*
* @author hoojo
* @createDate Nov 27,2010 1:14:52 PM
*/
@Test
public void readXML4InputStream() {
try {
String s = "<object-stream><com.hoo.entity.Student><id>0</id><name>jack</name>"
+ "</com.hoo.entity.Student><com.hoo.entity.Birthday><birthday>2010-05-33</birthday>"
+ "</com.hoo.entity.Birthday><byte>22</byte><boolean>true</boolean><float>22.0</float>"
+ "<string>hello</string></object-stream>";
failRed("---------ObjectInputStream## XML --> javaObject---------");
StringReader reader = new StringReader(s);
in = xstream.createObjectInputStream(reader);
Student stu = (Student) in.readObject();
Birthday b = (Birthday) in.readObject();
byte i = in.readByte();
boolean bo = in.readBoolean();
float f = in.readFloat();
String str = in.readUTF();
System.out.println(stu);
System.out.println(b);
System.out.println(i);
System.out.println(bo);
System.out.println(f);
System.out.println(str);
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* <b>function:</b>将XML字符串转换成Java对象
*
* @author hoojo
* @createDate Nov 27,2010 2:39:06 PM
*/
@SuppressWarnings("unchecked")
@Test
public void readXml2Object() {
try {
failRed("-----------Xml >>> Bean--------------");
Student stu = (Student) xstream.fromXML(xstream.toXML(bean));
fail(stu.toString());
List<Student> list = new ArrayList<Student>();
list.add(bean);// add
Map<String,bean);// put
bean = new Student();
bean.setAddress("china");
bean.setEmail("tom@125.com");
bean.setId(2);
bean.setName("tom");
Birthday day = new Birthday("2010-11-22");
bean.setBirthday(day);
list.add(bean);// add
map.put("No.2",bean);// put
bean = new Student();
bean.setName("jack");
list.add(bean);// add
map.put("No.3",bean);// put
failRed("==========XML >>> List===========");
List<Student> studetns = (List<Student>) xstream.fromXML(xstream.toXML(list));
fail("size:" + studetns.size());// 3
for (Student s : studetns) {
fail(s.toString());
}
failRed("==========XML >>> Map===========");
Map<String,Student> maps = (Map<String,Student>) xstream.fromXML(xstream.toXML(map));
fail("size:" + maps.size());// 3
Set<String> key = maps.keySet();
Iterator<String> iter = key.iterator();
while (iter.hasNext()) {
String k = iter.next();
fail(k + ":" + map.get(k));
}
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* <b>function:</b>XStream结合JettisonMappedXmlDriver驱动，转换Java对象到JSON 需要添加jettison jar
*
* @author hoojo
* @createDate Nov 27,2010 1:23:18 PM
*/
@Test
public void writeEntity2JETTSON() {
failRed("=======JettisonMappedXmlDriver===JavaObject >>>> JaonString=========");
xstream = new XStream(new JettisonMappedXmlDriver());
xstream.setMode(XStream.NO_REFERENCES);
xstream.alias("student",Student.class);
fail(xstream.toXML(bean));
}
/**
* <b>function:</b>用XStream结合JsonHierarchicalStreamDriver驱动 转换java对象为JSON字符串
*
* @author hoojo
* @createDate Nov 27,2010 1:16:46 PM
*/
@Test
public void writeEntiry2JSON() {
failRed("======JsonHierarchicalStreamDriver====JavaObject >>>> JaonString=========");
xstream = new XStream(new JsonHierarchicalStreamDriver());
// xstream.setMode(XStream.NO_REFERENCES);
xstream.alias("student",Student.class);
failRed("-------Object >>>> JSON---------");
fail(xstream.toXML(bean));
// failRed("========JsonHierarchicalStreamDriver==删除根节点=========");
// 删除根节点
xstream = new XStream(new JsonHierarchicalStreamDriver() {
public HierarchicalStreamWriter createWriter(Writer out) {
return new JsonWriter(out,JsonWriter.DROP_ROOT_MODE);
}
});
// xstream.setMode(XStream.NO_REFERENCES);
xstream.alias("student",Student.class);
fail(xstream.toXML(bean));
}
@Test
public void writeList2JSON() {
failRed("======JsonHierarchicalStreamDriver====JavaObject >>>> JaonString=========");
JsonHierarchicalStreamDriver driver = new JsonHierarchicalStreamDriver();
xstream = new XStream(driver);
// xstream = new XStream(new JettisonMappedXmlDriver());//转换错误
// xstream.setMode(XStream.NO_REFERENCES);
xstream.alias("student",Student.class);
List<Student> list = new ArrayList<Student>();
list.add(bean);// add
bean = new Student();
bean.setAddress("china");
bean.setEmail("tom@125.com");
bean.setId(2);
bean.setName("tom");
Birthday day = new Birthday("2010-11-22");
bean.setBirthday(day);
list.add(bean);// add
bean = new Student();
bean.setName("jack");
list.add(bean);// add
fail(xstream.toXML(list));
// failRed("========JsonHierarchicalStreamDriver==删除根节点=========");
// 删除根节点
xstream = new XStream(new JsonHierarchicalStreamDriver() {
public HierarchicalStreamWriter createWriter(Writer out) {
return new JsonWriter(out,JsonWriter.DROP_ROOT_MODE);
}
});
xstream.alias("student",Student.class);
fail(xstream.toXML(list));
}
@Test
public void writeMap2JSON() {
failRed("======JsonHierarchicalStreamDriver==== Map >>>> JaonString=========");
xstream = new XStream(new JsonHierarchicalStreamDriver());
// xstream = new XStream(new JettisonMappedXmlDriver());
xstream.alias("student",Student.class);
Map<String,Student>();
map.put("No.1",bean);// put
bean = new Student();
bean.setAddress("china");
bean.setEmail("tom@125.com");
bean.setId(2);
bean.setName("tom");
bean.setBirthday(new Birthday("2010-11-21"));
map.put("No.2",bean);// put
bean = new Student();
bean.setName("jack");
map.put("No.3",bean);// put
fail(xstream.toXML(map));
// failRed("========JsonHierarchicalStreamDriver==删除根节点=========");
// 删除根节点
xstream = new XStream(new JsonHierarchicalStreamDriver() {
public HierarchicalStreamWriter createWriter(Writer out) {
return new JsonWriter(out,Student.class);
fail(xstream.toXML(map));
}
/**
* <b>function:</b>JsonHierarchicalStreamDriver可以将简单的json字符串转换成java对象，list、map转换不成功；
* JsonHierarchicalStreamDriver读取JSON字符串到java对象出错
*
* @author hoojo
* @createDate Nov 27,2010 1:22:26 PM
* @throws JSONException
*/
@Test
public void readJSON2Object() throws JSONException {
String json = "{\"student\": {" + "\"id\": 1," + "\"name\": \"haha\"," + "\"email\": \"email\","
+ "\"address\": \"address\"," + "\"birthday\": {" + "\"birthday\": \"2010-11-22\"" + "}" + "}}";
// JsonHierarchicalStreamDriver读取JSON字符串到java对象出错，但JettisonMappedXmlDriver可以
xstream = new XStream(new JettisonMappedXmlDriver());
xstream.alias("student",Student.class);
fail(xstream.fromXML(json).toString());
// JettisonMappedXmlDriver转换List集合出错，但JsonHierarchicalStreamDriver可以转换正确
// xstream = new XStream(new JsonHierarchicalStreamDriver());
// xstream.alias("student",Student.class);
//
// // JettisonMappedXmlDriver 转换的字符串
// // {"list":{"student":[{"id":1,"name":"haha","email":"email","address":"address","birthday":[{},"2010-11-22"]}]},"student":{"id":2,"name":"tom","email":"tom@125.com","address":"china","2010-11-22"]}}
// json = "{\"list\": [{" + "\"id\": 1,"
// + "\"address\": \"address\"," + "\"birthday\": {" + "\"birthday\": \"2010-11-22\"" + "}" + "},{"
// + "\"id\": 2," + "\"name\": \"tom\"," + "\"email\": \"tom@125.com\"," + "\"address\": \"china\","
// + "\"birthday\": {" + "\"birthday\": \"2010-11-22\"" + "}" + "}]}";
// System.out.println(json);// 用js转换成功
// List list = (List) xstream.fromXML(json);
//System.out.println(list.size());// 0好像转换失败
}
}
3，运行结果：
---------annotation Bean --> XML--------- <class 名称="一班"> <Students> <id>1</id> <name>jack</name> <email>jack@email.com</email> <address>china</address> <birthday> <birthday>2010-11-22</birthday> </birthday> </Students> <Students> <id>0</id> <name>jack</name> </Students> <created>1439030984003</created> </class> ---------ObjectInputStream## XML --> javaObject--------- jack#0#null#null#null 2010-05-33 22 true 22.0 hello ---------ObjectOutputStream # JavaObject--> XML--------- <object-stream> <com.hoo.entity.Student> <id>0</id> <name>jack</name> </com.hoo.entity.Student> <com.hoo.entity.Birthday> <birthday>2010-05-33</birthday> </com.hoo.entity.Birthday> <byte>22</byte> <boolean>true</boolean> <float>22.0</float> <string>hello</string> </object-stream>-----------Xml >>> Bean-------------- ==========XML >>> List=========== ==========XML >>> Map=========== =======JettisonMappedXmlDriver===JavaObject >>>> JaonString========= ---------annotation Bean --> XML--------- ======JsonHierarchicalStreamDriver====JavaObject >>>> JaonString========= -------Object >>>> JSON--------- ======JsonHierarchicalStreamDriver====JavaObject >>>> JaonString========= ---------Map --> XML--------- ======JsonHierarchicalStreamDriver==== Map >>>> JaonString=========
4，git源代码地址：
https://git.oschina.net/coderdream/xsteam-demo 5，源代码下载： 原文链接：https://www.f2er.com/xml/296330.html
