一、前言

1、XStream官网

http://x-stream.github.io

2、XStream是什么

XStream是一个简单的基于Java的类库，用来将Java对象序列化成XML(JSON)或反序列化为对象(即：可以轻易的将Java对象和XML文档相互转换)

3、XSteam能干什么

XStream在运行时使用Java反射机制对要进行序列化的对象树的结构进行探索，并不需要对对象作出修改。XStream可以序列化内部字段，包括私private和final字段，并且支持非公开类以及内部类。

在缺省情况下，XStream不需要配置映射关系，对象和字段将映射为同名XML元素。但是当对象和字段名与XML中的元素名不同时，XStream支持指定别名。XStream支持以方法调用的方式，或是Java 标注的方式指定别名。

XStream在进行数据类型转换时，使用系统缺省的类型转换器。同时，也支持用户自定义的类型转换器。

4、XStream特点**使用方便 **- XStream的API提供了一个高层次外观，以简化常用的用例

**无需创建映射 **- XStream的API提供了默认的映射大部分对象序列化

性能 - XStream快速和低内存占用，适合于大对象图或系统

干净的XML - XStream创建一个干净和紧凑XML结果，这很容易阅读

不需要修改对象 - XStream可序列化的内部字段，如private和final字段，支持非公开类和内部类。默认构造函数不是强制性的要求

完整对象图支持 - XStream允许保持在对象模型中遇到的重复引用，并支持循环引用

可自定义的转换策略 - 定制策略可以允许特定类型的定制被表示为XML的注册

安全框架 - XStream提供了一个公平控制有关解组的类型，以防止操纵输入安全问题

**错误消息 **- 出现异常是由于格式不正确的XML时，XStream抛出一个统一的例外，提供了详细的诊断，以解决这个问题

另一种输出格式 - XStream支持其它的输出格式，如JSON

5、XStream常见的用途

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二、XStream入门

1、添加XSteam依赖

com.thoughtworks.xstream

xstream

1.4.12

org.codehaus.jettison

jettison

1.4.1

2、XStream基本使用

package io.github.xstream.test01;

​

import com.thoughtworks.xstream.XStream;

import com.thoughtworks.xstream.io.json.JettisonMappedXmlDriver;

import lombok.AllArgsConstructor;

import lombok.ToString;

​

public class XStreamTest01 {

public static void main(String[] args) {

Student student = new Student("张三", 20);

XStream xStream = new XStream();//需要XPP3库

//XStream xStream = new XStream(new DomDriver());//不需要XPP3库

//XStream xStream = new XStream(new StaxDriver());//不需要XPP3库开始使用Java 6

//XML序列化

String xml = xStream.toXML(student);

System.out.println(xml);

//XML反序列化

student = (Student) xStream.fromXML(xml);

System.out.println(student);

​

xStream = new XStream(new JettisonMappedXmlDriver());

xStream.setMode(XStream.NO_REFERENCES);

//Json序列化

String json = xStream.toXML(student);

System.out.println(json);

//Json反序列

student = (Student) xStream.fromXML(json);

System.out.println(student);

}

}

​

@AllArgsConstructor

@ToString

class Student {

private String name;

private int age;

}

3、程序运行结果

张三

20

Security framework of XStream not initialized, XStream is probably vulnerable.

Student(name=张三, age=20)

{"io.github.xstream.test01.Student":{"name":"张三","age":20}}

Student(name=张三, age=20)

Security framework of XStream not initialized, XStream is probably vulnerable.

注意：文中使用到的Lombok注解，Lombok依赖自行添加；XStream序列化XML时需要引用的jar包：xstream-[version].jar、xpp3-[version].jar、xmlpull-[version].jar，当引入xstream依赖后会自动依赖xpp3、xmlpull依赖。XStream序列化JSON需要引用的jar包：jettison-[version].jar。

使用XStream序列化时，对JavaBean没有任何限制。JavaBean的字段可以是私有的，也可以没有getter或setter方法，还可以没有默认的构造函数。

XStream序列化XML时可以允许用户使用不同的XML解析器，用户可以使用一个标准的JAXP DOM解析器或自Java 6集成STAX解析器。这样用户就不需要依赖xpp3-[version].jar。

三、XStream混叠****

1、混叠是一种技术来定制生成XML或者使用XStream特定的格式化XML。假设，一个下面的XML格式是用于序列化/反序列化Student对象。

小米

小米手机的描述

苹果

苹果手机的描述

2、根椐上面的XML格式，我们创建实体类

@AllArgsConstructor

@ToString

class Student {

private String studentName;

private List phones;

}

​

@AllArgsConstructor

@ToString

class Phone {

private String brand;

private String description;

}

3、执行代码

package io.github.xstream.test02;

​

import com.thoughtworks.xstream.XStream;

import lombok.AllArgsConstructor;

import lombok.ToString;

​

import java.util.ArrayList;

import java.util.List;

​

public class XStreamTest02 {

public static void main(String[] args) {

List phones = new ArrayList<>();

phones.add(new Phone("小米手机", "小米手机的描述"));

phones.add(new Phone("苹果手机", "苹果手机的描述"));

Student student = new Student("张三", phones);

​

XStream xStream = new XStream();//需要XPP3库

//XML序列化

String xml = xStream.toXML(student);

System.out.println(xml);

}

}

​

@AllArgsConstructor

@ToString

class Student {

private String studentName;

private List phones;

}

​

@AllArgsConstructor

@ToString

class Phone {

private String brand;

private String description;

}

4、验证输出

张三

小米手机

小米手机的描述

苹果手机

苹果手机的描述

在上面的结果，我们已经看到了Student对象名称是完全合格的。要替换它作为学生的标签，按照**四、XStream类混叠**的步骤

另外，在上述结果中可以看出，所需studentName要重命名来命名。要替换它，按照**五、XStream字段混叠**的步骤

在上面的结果，我们可以看到手机标记被添加成为手机列表。替换它，按照**六、XStream隐式集合混叠**的步骤

在上面的结果，我们可以看到这个名字来作为一个子节点，需要将它作为根节点的属性。替换它，按照**七、XStream属性混叠**的步骤

四、****XStream****类混叠

1、类混叠是用来创建一个类的XML完全限定名称的别名。让我们修改XStreamTest02例子，将下面的代码添加到XStreamTest02例子里面

xStream.alias("student", Person02.class);

xStream.alias("phone", Phone.class);

2、执行代码

package io.github.xstream.test02;

​

import com.thoughtworks.xstream.XStream;

import lombok.AllArgsConstructor;

import lombok.ToString;

​

import java.util.ArrayList;

import java.util.List;

​

public class XStreamTest02 {

public static void main(String[] args) {

List phones = new ArrayList<>();

phones.add(new Phone("小米手机", "小米手机的描述"));

phones.add(new Phone("苹果手机", "苹果手机的描述"));

Student student = new Student("张三", phones);

​

XStream xStream = new XStream();//需要XPP3库

xStream.alias("student", Student.class);

xStream.alias("phone", Phone.class);

​

//XML序列化

String xml = xStream.toXML(student);

System.out.println(xml);

}

}

​

@AllArgsConstructor

@ToString

class Student {

private String studentName;

private List phones;

}

​

@AllArgsConstructor

@ToString

class Phone {

private String brand;

private String description;

}

3、执行结果

张三

小米手机

小米手机的描述

苹果手机

苹果手机的描述

可以看到和分别被修改为了和

五、****XStream****字段混叠

1、字段混叠用于创建以XML字段的别名。让我们再次修改原来的XStreamTest02例子，将下面的代码添加到XStreamTest02例子里面

xStream.aliasField("name", Student.class, "studentName");

2、执行代码

package io.github.xstream.test02;

​

import com.thoughtworks.xstream.XStream;

import lombok.AllArgsConstructor;

import lombok.ToString;

​

import java.util.ArrayList;

import java.util.List;

​

public class XStreamTest02 {

public static void main(String[] args) {

List phones = new ArrayList<>();

phones.add(new Phone("小米手机", "小米手机的描述"));

phones.add(new Phone("苹果手机", "苹果手机的描述"));

Student student = new Student("张三", phones);

​

XStream xStream = new XStream();//需要XPP3库

xStream.alias("student", Student.class);

xStream.alias("phone", Phone.class);

xStream.aliasField("name", Student.class, "studentName");

​

//XML序列化

String xml = xStream.toXML(student);

System.out.println(xml);

}

}

​

@AllArgsConstructor

@ToString

class Student {

private String studentName;

private List phones;

}

​

@AllArgsConstructor

@ToString

class Phone {

private String brand;

private String description;

}

3、执行结果

张三

小米手机

小米手机的描述

苹果手机

苹果手机的描述

可以看到被修改为了

六、****XStream****隐式集合混叠

1、隐式集合混叠时使用的集合是表示在XML无需显示根。例如，在我们的例子中，我们需要一个接一个，但不是在根节点来显示每一个节点。让我们再次修改原来的XStreamTest02例子，将下面的代码添加到XStreamTest02例子里面

xStream.addImplicitCollection(Student.class, "phones");

2、执行代码

package io.github.xstream.test02;

​

import com.thoughtworks.xstream.XStream;

import lombok.AllArgsConstructor;

import lombok.ToString;

​

import java.util.ArrayList;

import java.util.List;

​

public class XStreamTest02 {

public static void main(String[] args) {

List phones = new ArrayList<>();

phones.add(new Phone("小米手机", "小米手机的描述"));

phones.add(new Phone("苹果手机", "苹果手机的描述"));

Student student = new Student("张三", phones);

​

XStream xStream = new XStream();//需要XPP3库

xStream.alias("student", Student.class);

xStream.alias("phone", Phone.class);

xStream.aliasField("name", Student.class, "studentName");

xStream.addImplicitCollection(Student.class, "phones");

​

//XML序列化

String xml = xStream.toXML(student);

System.out.println(xml);

}

}

​

@AllArgsConstructor

@ToString

class Student {

private String studentName;

private List phones;

}

​

@AllArgsConstructor

@ToString

class Phone {

private String brand;

private String description;

}

3、执行结果

张三

小米手机

小米手机的描述

苹果手机

苹果手机的描述

可以看到被隐藏了

七、****XStream****属性混叠

1、属性混叠用于创建一个成员变量作为XML属性序列化。让我们再次修改原来的XStreamTest02例子，将下面的代码添加到XStreamTest02例子里面

xStream.useAttributeFor(Student.class, "studentName");

2、执行代码

package io.github.xstream.test02;

​

import com.thoughtworks.xstream.XStream;

import lombok.AllArgsConstructor;

import lombok.ToString;

​

import java.util.ArrayList;

import java.util.List;

​

public class XStreamTest02 {

public static void main(String[] args) {

List phones = new ArrayList<>();

phones.add(new Phone("小米手机", "小米手机的描述"));

phones.add(new Phone("苹果手机", "苹果手机的描述"));

Student student = new Student("张三", phones);

​

XStream xStream = new XStream();//需要XPP3库

xStream.alias("student", Student.class);

xStream.alias("phone", Phone.class);

xStream.aliasField("name", Student.class, "studentName");

xStream.addImplicitCollection(Student.class, "phones");

xStream.useAttributeFor(Student.class, "studentName");

​

//XML序列化

String xml = xStream.toXML(student);

System.out.println(xml);

}

}

​

@AllArgsConstructor

@ToString

class Student {

private String studentName;

private List phones;

}

​

@AllArgsConstructor

@ToString

class Phone {

private String brand;

private String description;

}

3、执行结果

小米手机

小米手机的描述

苹果手机

苹果手机的描述

可以看到被作为了的属性

八、****XStream****包混叠

1、包混叠用于创建一个类XML的完全限定名称的别名到一个新的限定名称。让我们再次修改原来的XStreamTest02例子，将下面代码

xStream.alias("student", Student.class);

xStream.alias("phone", Phone.class);

修改为

xStream.aliasPackage("xx.xx.xx.xx", "io.github.xstream.test02");

2、执行代码

package io.github.xstream.test02;

​

import com.thoughtworks.xstream.XStream;

import lombok.AllArgsConstructor;

import lombok.ToString;

​

import java.util.ArrayList;

import java.util.List;

​

public class XStreamTest02 {

public static void main(String[] args) {

List phones = new ArrayList<>();

phones.add(new Phone("小米手机", "小米手机的描述"));

phones.add(new Phone("苹果手机", "苹果手机的描述"));

Student student = new Student("张三", phones);

​

XStream xStream = new XStream();//需要XPP3库

// xStream.alias("student", Student.class);

// xStream.alias("phone", Phone.class);

xStream.aliasPackage("xx.xx.xx.xx", "io.github.xstream.test02");

xStream.aliasField("name", Student.class, "studentName");

xStream.addImplicitCollection(Student.class, "phones");

xStream.useAttributeFor(Student.class, "studentName");

​

//XML序列化

String xml = xStream.toXML(student);

System.out.println(xml);

}

}

​

@AllArgsConstructor

@ToString

class Student {

private String studentName;

private List phones;

}

​

@AllArgsConstructor

@ToString

class Phone {

private String brand;

private String description;

}

3、执行结果

小米手机

小米手机的描述

苹果手机

苹果手机的描述

可以看到包名由io.github.xstream.test02替换为了xx.xx.xx.xx

九、****XStream****注解

1、前面的四、五、六、七、八步骤都是通过代码操作的

//xStream.alias("student", Student.class);

//xStream.alias("phone", Phone.class);

xStream.aliasPackage("xx.xx.xx.xx", "io.github.xstream.test02");

xStream.aliasField("name", Student.class, "studentName");

xStream.addImplicitCollection(Student.class, "phones");

xStream.useAttributeFor(Student.class, "studentName");

2、XStream同时也支持注解，使用注解会变得简单也会达到相同的效果

package io.github.xstream.test03;

​

import com.thoughtworks.xstream.XStream;

import com.thoughtworks.xstream.annotations.*;

import com.thoughtworks.xstream.converters.basic.BooleanConverter;

import lombok.AllArgsConstructor;

import lombok.Data;

import lombok.ToString;

​

import java.util.ArrayList;

import java.util.List;

​

public class XStreamTest03 {

public static void main(String[] args) {

List phones = new ArrayList<>();

phones.add(new Phone("小米手机", "小米手机的描述"));

phones.add(new Phone("苹果手机", "苹果手机的描述"));

Student student = new Student("张三", phones, 20, true);

XStream xStream = new XStream();//需要XPP3库

//xStream.processAnnotations(new Class[]{Student.class});

xStream.autodetectAnnotations(true);

//XML序列化

String xml = xStream.toXML(student);

System.out.println(xml);

}

}

​

@AllArgsConstructor

@ToString

//别名注解

@XStreamAlias("student")

class Student {

@XStreamAlias("name")

//把字段节点设置成属性

@XStreamAsAttribute

private String studentName;

//省略集合根节点

@XStreamImplicit

private List phones;

//隐藏字段

@XStreamOmitField

private int age;

//设置转换器

@XStreamConverter(value = BooleanConverter.class, booleans = {false}, strings = {"男", "女"})

private boolean sex;

}

​

@AllArgsConstructor

@ToString

@XStreamAlias("phone")

class Phone {

private String brand;

private String description;

}

3、使用注解的话，需要XML序列化之前添加如下代码

xStream.autodetectAnnotations(true);

或者

xStream.processAnnotations(new Class[]{Student.class});

4、执行结果

小米手机

小米手机的描述

苹果手机

苹果手机的描述

男

使用注解我们也可以看到也能达到相同的效果

注意：当使用XStream对象处理一个被注解的类型时，XStream对象也会处理所有与其相关的类型的注解信息，即该类型的父类、父接口、所有子类的注解。

十、****XStream自定义****转换器

1、XStream自带的转换器

XStream内部有许多转换器，用于JavaBean对象到XML或JSON之间的转换。这些转换器的详细信息网址：http://x-stream.github.io/converters.html

2、使用自定义转换器

package io.github.xstream.test04;

​

import com.thoughtworks.xstream.XStream;

import com.thoughtworks.xstream.annotations.XStreamAlias;

import lombok.AllArgsConstructor;

import lombok.Getter;

import lombok.Setter;

import lombok.ToString;

​

public class XStreamTest04 {

public static void main(String[] args) {

Student student =new Student("张三",19);

XStream xStream = new XStream();

//注册转换器

xStream.registerConverter(new StudentConverter());

//序列化

String xml = xStream.toXML(student);

System.out.println(xml);

//反序列化

student=(Student)xStream.fromXML(xml);

System.out.println(student);

}

}

​

@Getter

@Setter

@ToString

@AllArgsConstructor

class Student {

private String name;

private int age;

}

自定义转换器

package io.github.xstream.test04;

​

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;

​

public class StudentConverter implements Converter {

//定义转换器能转换的JavaBean类型

@Override

public boolean canConvert(Class type) {

return type.equals(Student.class);

}

​

//把对象序列化成XML或JSON

@Override

public void marshal(Object value, HierarchicalStreamWriter writer,

MarshallingContext context) {

Student student = (Student) value;

writer.startNode("姓名");

writer.setValue(student.getName());

writer.endNode();

writer.startNode("年龄");

writer.setValue(student.getAge() + "");

writer.endNode();

writer.startNode("转换器");

writer.setValue("自定义的转换器");

writer.endNode();

}

​

//把XML或JSON反序列化成对象

@Override

public Object unmarshal(HierarchicalStreamReader reader,

UnmarshallingContext context) {

Student student = new Student("", -1);

reader.moveDown();

student.setName(reader.getValue());

reader.moveUp();

reader.moveDown();

student.setAge(Integer.parseInt(reader.getValue()));

reader.moveUp();

return student;

}

}

3、执行结果

张三姓名>

19年龄>

自定义的转换器转换器>

Security framework of XStream not initialized, XStream is probably vulnerable.

Student(name=张三, age=19)

4、常用的转换器接口与抽象类

SingleValueConverter：单值转换接口

AbstractSingleValueConverter：单值转换抽象类

Converter：常规转换器接口

十一、****XStream****对象流

1、对象输出流

package io.github.xstream.test05;

​

import com.thoughtworks.xstream.XStream;

import com.thoughtworks.xstream.annotations.XStreamAlias;

import com.thoughtworks.xstream.annotations.XStreamAsAttribute;

import lombok.AllArgsConstructor;

import lombok.ToString;

​

import java.io.*;

​

public class XStreamTest05 {

public static void main(String[] args) throws IOException, ClassNotFoundException {

XStreamTest05 xStreamTest04 = new XStreamTest05();

String path = "F:\\test.txt";

XStream xStream = new XStream();//需要XPP3库

xStream.processAnnotations(Student.class);

xStream.autodetectAnnotations(true);

xStreamTest04.writeObject(xStream, path);

}

​

//对象输出流方法

public void writeObject(XStream xStream, String path) throws IOException {

Student zs = new Student("张三", 20);

Student ls = new Student("李四", 21);

Student ww = new Student("王五", 22);

ObjectOutputStream objectOutputStream = xStream.createObjectOutputStream(new FileOutputStream(path));

objectOutputStream.writeObject(zs);

objectOutputStream.writeObject(ls);

objectOutputStream.writeObject(ww);

objectOutputStream.writeObject("totalStudent");

objectOutputStream.writeInt(3);

objectOutputStream.close();

}

}

​

@AllArgsConstructor

@ToString

//别名注解

@XStreamAlias("student")

class Student {

@XStreamAlias("name")

//把字段节点设置成属性

@XStreamAsAttribute

private String studentName;

private int age;

}

2、在指定路径中打开test.txt文件，查看执行结果

20

21

22

totalStudent

3

注意：XStream对象流是通过标准java.io.ObjectOutputStream和java.io.ObjectInputStream对象。因为XML文档只能有一个根节点，必须包装在一个序列化的所有元素额外的根节点。这个根节点默认为上面的例子所示。

3、对象输入流

package io.github.xstream.test05;

​

import com.thoughtworks.xstream.XStream;

import com.thoughtworks.xstream.annotations.XStreamAlias;

import com.thoughtworks.xstream.annotations.XStreamAsAttribute;

import lombok.AllArgsConstructor;

import lombok.ToString;

​

import java.io.*;

​

public class XStreamTest05 {

public static void main(String[] args) throws IOException, ClassNotFoundException {

XStreamTest05 xStreamTest04 = new XStreamTest05();

String path = "F:\\test.txt";

XStream xStream = new XStream();//需要XPP3库

xStream.processAnnotations(Student.class);

xStream.autodetectAnnotations(true);

xStreamTest04.readObject(xStream, path);

}

​

//对象输入流方法

public void readObject(XStream xStream, String path) throws IOException, ClassNotFoundException {

ObjectInputStream objectInputStream = xStream.createObjectInputStream(new FileInputStream(path));

System.out.println((Student) objectInputStream.readObject());

System.out.println((Student) objectInputStream.readObject());

System.out.println((Student) objectInputStream.readObject());

System.out.println(objectInputStream.readObject());

System.out.println(objectInputStream.readInt());

}

}

​

@AllArgsConstructor

@ToString

//别名注解

@XStreamAlias("student")

class Student {

@XStreamAlias("name")

//把字段节点设置成属性

@XStreamAsAttribute

private String studentName;

private int age;

}

4、执行结果

Student(studentName=张三, age=20)

Student(studentName=李四, age=21)

Student(studentName=王五, age=22)

totalStudent

3

**十二、****XStream持久化API******

1、保存Java对象

​package io.github.xstream.test06;

​

import com.thoughtworks.xstream.persistence.FilePersistenceStrategy;

import com.thoughtworks.xstream.persistence.PersistenceStrategy;

import com.thoughtworks.xstream.persistence.XmlArrayList;

import lombok.AllArgsConstructor;

import lombok.ToString;

​

import java.io.File;

import java.util.List;

​

public class XStreamTest06 {

public static void main(String[] args) {

XStreamTest06 xStreamTest06=new XStreamTest06();

xStreamTest06.saveObject();

}

​

//保存Java对象

public void saveObject(){

PersistenceStrategy strategy = new FilePersistenceStrategy(new File("F:\\"));

List list = new XmlArrayList(strategy);

list.add(new Student("张三",13));

list.add(new Student("李四",21));

list.add(new Student("王五",17));

}

}

​

@ToString

@AllArgsConstructor

class Student {

private String name;

private int age;

}

2、运行程序结果，在F磁盘的根路径可以看到有三个文件:int@0.xml、int@1.xml、int@2.xml，每个对象都被序列化到XML文件里

3、读取并删除JavaBean对象

package io.github.xstream.test06;

​

import com.thoughtworks.xstream.persistence.FilePersistenceStrategy;

import com.thoughtworks.xstream.persistence.PersistenceStrategy;

import com.thoughtworks.xstream.persistence.XmlArrayList;

import lombok.AllArgsConstructor;

import lombok.ToString;

​

import java.io.File;

import java.util.Iterator;

import java.util.List;

​

public class XStreamTest06 {

public static void main(String[] args) {

XStreamTest06 xStreamTest06 = new XStreamTest06();

xStreamTest06.deleteObject();

}

//读取并删除Java对象

public void deleteObject() {

PersistenceStrategy strategy = new FilePersistenceStrategy(new File("F:\\"));

List list = new XmlArrayList(strategy);

for (Iterator it = list.iterator(); it.hasNext(); ) {

System.out.println((Student) it.next());

//删除对象序列化文件

it.remove();

}

}

}

​

@ToString

@AllArgsConstructor

class Student {

private String name;

private int age;

}

4、运行程序结果，可以看到把F磁盘的根路径int@0.xml、int@1.xml、int@2.xml文件删除了

Security framework of XStream not initialized, XStream is probably vulnerable.

Student(name=张三, age=13)

Student(name=李四, age=21)

Student(name=王五, age=17)

十三、****XStream****操作JSON

1、XStream序列化JSON的重命名

package io.github.xstream.test07;

​

import com.thoughtworks.xstream.XStream;

import com.thoughtworks.xstream.annotations.XStreamAlias;

import com.thoughtworks.xstream.io.json.JettisonMappedXmlDriver;

import io.github.xstream.test04.StudentConverter;

import lombok.AllArgsConstructor;

import lombok.Getter;

import lombok.Setter;

import lombok.ToString;

​

public class XStreamTest07 {

public static void main(String[] args) {

XStreamTest07 xStreamTest07 = new XStreamTest07();

xStreamTest07.serializeJson();

}

​

public void serializeJson() {

Student student = new Student("张三", 19);

XStream xStream = new XStream(new JettisonMappedXmlDriver());//设置Json解析器

xStream.autodetectAnnotations(true);

//JSON序列化

String xml = xStream.toXML(student);

System.out.println(xml);

//JSON反序列化

student = (Student) xStream.fromXML(xml);

System.out.println(student);

}

}

​

@ToString

@AllArgsConstructor

@XStreamAlias("人")

class Student {

@XStreamAlias("姓名")

private String name;

@XStreamAlias("年龄")

private int age;

}

2、运行结果

{"人":{"姓名":"张三","年龄":19}}

Student(name=张三, age=19)

Security framework of XStream not initialized, XStream is probably vulnerable.

注意：XStream序列化JSON的重命名的方式与其序列化成XML的方式一样！

3、去掉序列化JSON的根节点

​package io.github.xstream.test07;

​

import com.thoughtworks.xstream.XStream;

import com.thoughtworks.xstream.annotations.XStreamAlias;

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;

import io.github.xstream.test04.StudentConverter;

import lombok.AllArgsConstructor;

import lombok.Getter;

import lombok.Setter;

import lombok.ToString;

​

import java.io.Writer;

​

public class XStreamTest07 {

public static void main(String[] args) {

XStreamTest07 xStreamTest07 = new XStreamTest07();

xStreamTest07.removeRootNode();

}

​

public void removeRootNode() {

Student student = new Student("张三", 19);

XStream xStream = new XStream(new JsonHierarchicalStreamDriver() {

public HierarchicalStreamWriter createWriter(Writer writer) {

return new JsonWriter(writer, JsonWriter.DROP_ROOT_MODE);

}

});

//Json序列化

String xml = xStream.toXML(student);

System.out.println(xml);

}

}

​

@ToString

@AllArgsConstructor

@XStreamAlias("人")

class Student {

@XStreamAlias("姓名")

private String name;

@XStreamAlias("年龄")

private int age;

}

4、运行结果

{

"name": "张三",

"age": 19

}

注意：去掉根节点后的JSON串是不能反序列化的，因为XStream不知道它的类型。

5、JSON的解析器区别

前面两个例子使用了不同的JSON解析器，这里说明他们的不同之处：JettisonMappedXmlDriver：是支持序列化和反序列化Json的。

JsonHierarchicalStreamDriver：只支持序列化，不支持反序列化。