XStream學習手冊

本文轉載自查看原文 2020-06-04 11:58 864 Java

一、前言

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1、XStream官網

http://x-stream.github.io

2、XStream是什么

XStream是一個簡單的基於Java的類庫，用來將Java對象序列化成XML（JSON）或反序列化為對象(即：可以輕易的將Java對象和XML文檔相互轉換)

3、XSteam能干什么

XStream在運行時使用Java反射機制對要進行序列化的對象樹的結構進行探索，並不需要對對象作出修改。XStream可以序列化內部字段，包括私private和final字段，並且支持非公開類以及內部類。

在缺省情況下，XStream不需要配置映射關系，對象和字段將映射為同名XML元素。但是當對象和字段名與XML中的元素名不同時，XStream支持指定別名。XStream支持以方法調用的方式，或是Java 標注的方式指定別名。

XStream在進行數據類型轉換時，使用系統缺省的類型轉換器。同時，也支持用戶自定義的類型轉換器。

4、XStream特點

使用方便 - XStream的API提供了一個高層次外觀，以簡化常用的用例
無需創建映射 - XStream的API提供了默認的映射大部分對象序列化
性能 - XStream快速和低內存占用，適合於大對象圖或系統
干凈的XML - XStream創建一個干凈和緊湊XML結果，這很容易閱讀
不需要修改對象 - XStream可序列化的內部字段，如private和final字段，支持非公開類和內部類。默認構造函數不是強制性的要求
完整對象圖支持 - XStream允許保持在對象模型中遇到的重復引用，並支持循環引用
可自定義的轉換策略 - 定制策略可以允許特定類型的定制被表示為XML的注冊
安全框架 - XStream提供了一個公平控制有關解組的類型，以防止操縱輸入安全問題
錯誤消息 - 出現異常是由於格式不正確的XML時，XStream拋出一個統一的例外，提供了詳細的診斷，以解決這個問題
另一種輸出格式 - XStream支持其它的輸出格式，如JSON

5、XStream常見的用途

傳輸、持久化、配置、單元測試

二、XStream入門

1、添加XSteam依賴

<dependency> <groupId>com.thoughtworks.xstream</groupId> <artifactId>xstream</artifactId> <version>1.4.12</version> </dependency> <dependency> <groupId>org.codehaus.jettison</groupId> <artifactId>jettison</artifactId> <version>1.4.1</version> </dependency>

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("張三", 20); XStream xStream = new XStream();//需要XPP3庫 //XStream xStream = new XStream(new DomDriver());//不需要XPP3庫 //XStream xStream = new XStream(new StaxDriver());//不需要XPP3庫開始使用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、程序運行結果

<io.github.xstream.test01.Student>
  <name>張三</name>
  <age>20</age>
</io.github.xstream.test01.Student>
Security framework of XStream not initialized, XStream is probably vulnerable.
Student(name=張三, age=20)
{"io.github.xstream.test01.Student":{"name":"張三","age":20}}
Student(name=張三, age=20)
Security framework of XStream not initialized, XStream is probably vulnerable.

注意：文中使用到的Lombok注解，Lombok依賴自行添加；XStream序列化XML時需要引用的jar包：xstream-[version].jar、xpp3-[version].jar、xmlpull-[version].jar，當引入xstream依賴后會自動依賴xpp3、xmlpull依賴。XStream序列化JSON需要引用的jar包：jettison-[version].jar。

使用XStream序列化時，對JavaBean沒有任何限制。JavaBean的字段可以是私有的，也可以沒有getter或setter方法，還可以沒有默認的構造函數。

XStream序列化XML時可以允許用戶使用不同的XML解析器，用戶可以使用一個標准的JAXP DOM解析器或自Java 6集成STAX解析器。這樣用戶就不需要依賴xpp3-[version].jar。

三、XStream混疊

1、混疊是一種技術來定制生成XML或者使用XStream特定的格式化XML。假設，一個下面的XML格式是用於序列化/反序列化Student對象。

<student name="張三"> <phone> <brand>小米</brand> <description>小米手機的描述</description> </phone> <phone> <brand>蘋果</brand> <description>蘋果手機的描述</description> </phone> </student>

2、根椐上面的XML格式，我們創建實體類

@AllArgsConstructor @ToString class Student { private String studentName; private List<Phone> phones; }  @AllArgsConstructor @ToString class Phone { private String brand; private String description; }

3、執行代碼

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<Phone> phones = new ArrayList<>(); phones.add(new Phone("小米手機", "小米手機的描述")); phones.add(new Phone("蘋果手機", "蘋果手機的描述")); Student student = new Student("張三", phones);  XStream xStream = new XStream();//需要XPP3庫 //XML序列化 String xml = xStream.toXML(student); System.out.println(xml); } }  @AllArgsConstructor @ToString class Student { private String studentName; private List<Phone> phones; }  @AllArgsConstructor @ToString class Phone { private String brand; private String description; }

4、驗證輸出

<io.github.xstream.test02.Student> <studentName>張三</studentName> <phones> <io.github.xstream.test02.Phone> <brand>小米手機</brand> <description>小米手機的描述</description> </io.github.xstream.test02.Phone> <io.github.xstream.test02.Phone> <brand>蘋果手機</brand> <description>蘋果手機的描述</description> </io.github.xstream.test02.Phone> </phones> </io.github.xstream.test02.Student>

在上面的結果，我們已經看到了Student對象名稱是完全合格的。要替換它作為學生的標簽，按照四、XStream類混疊的步驟

另外，在上述結果中可以看出，所需studentName要重命名來命名。要替換它，按照五、XStream字段混疊的步驟

在上面的結果，我們可以看到手機標記被添加成為手機列表。替換它，按照六、XStream隱式集合混疊的步驟

在上面的結果，我們可以看到這個名字來作為一個子節點，需要將它作為根節點的屬性。替換它，按照七、XStream屬性混疊的步驟

四、XStream類混疊

1、類混疊是用來創建一個類的XML完全限定名稱的別名。讓我們修改XStreamTest02例子，將下面的代碼添加到XStreamTest02例子里面

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

2、執行代碼

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<Phone> phones = new ArrayList<>(); phones.add(new Phone("小米手機", "小米手機的描述")); phones.add(new Phone("蘋果手機", "蘋果手機的描述")); Student student = new Student("張三", phones);  XStream xStream = new XStream();//需要XPP3庫 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<Phone> phones; }  @AllArgsConstructor @ToString class Phone { private String brand; private String description; }

3、執行結果

<student> <studentName>張三</studentName> <phones> <phone> <brand>小米手機</brand> <description>小米手機的描述</description> </phone> <phone> <brand>蘋果手機</brand> <description>蘋果手機的描述</description> </phone> </phones> </student>

可以看到<io.github.xstream.test02.Student>和<io.github.xstream.test02.Phone>分別被修改為了<student>和<phone>

五、XStream字段混疊

1、字段混疊用於創建以XML字段的別名。讓我們再次修改原來的XStreamTest02例子，將下面的代碼添加到XStreamTest02例子里面

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

2、執行代碼

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<Phone> phones = new ArrayList<>(); phones.add(new Phone("小米手機", "小米手機的描述")); phones.add(new Phone("蘋果手機", "蘋果手機的描述")); Student student = new Student("張三", phones);  XStream xStream = new XStream();//需要XPP3庫 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<Phone> phones; }  @AllArgsConstructor @ToString class Phone { private String brand; private String description; }

3、執行結果

<student> <name>張三</name> <phones> <phone> <brand>小米手機</brand> <description>小米手機的描述</description> </phone> <phone> <brand>蘋果手機</brand> <description>蘋果手機的描述</description> </phone> </phones> </student>

可以看到<studentName>被修改為了<name>

六、XStream隱式集合混疊

1、隱式集合混疊時使用的集合是表示在XML無需顯示根。例如，在我們的例子中，我們需要一個接一個，但不是在根節點來顯示每一個節點。讓我們再次修改原來的XStreamTest02例子，將下面的代碼添加到XStreamTest02例子里面

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

2、執行代碼

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<Phone> phones = new ArrayList<>(); phones.add(new Phone("小米手機", "小米手機的描述")); phones.add(new Phone("蘋果手機", "蘋果手機的描述")); Student student = new Student("張三", phones);  XStream xStream = new XStream();//需要XPP3庫 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<Phone> phones; }  @AllArgsConstructor @ToString class Phone { private String brand; private String description; }

3、執行結果

<student> <name>張三</name> <phone> <brand>小米手機</brand> <description>小米手機的描述</description> </phone> <phone> <brand>蘋果手機</brand> <description>蘋果手機的描述</description> </phone> </student>

可以看到<phones>被隱藏了

七、XStream屬性混疊

1、屬性混疊用於創建一個成員變量作為XML屬性序列化。讓我們再次修改原來的XStreamTest02例子，將下面的代碼添加到XStreamTest02例子里面

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

2、執行代碼

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<Phone> phones = new ArrayList<>(); phones.add(new Phone("小米手機", "小米手機的描述")); phones.add(new Phone("蘋果手機", "蘋果手機的描述")); Student student = new Student("張三", phones);  XStream xStream = new XStream();//需要XPP3庫 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<Phone> phones; }  @AllArgsConstructor @ToString class Phone { private String brand; private String description; }

3、執行結果

<student name="張三"> <phone> <brand>小米手機</brand> <description>小米手機的描述</description> </phone> <phone> <brand>蘋果手機</brand> <description>蘋果手機的描述</description> </phone> </student>

可以看到<name>被作為了<student>的屬性

八、XStream包混疊

1、包混疊用於創建一個類XML的完全限定名稱的別名到一個新的限定名稱。讓我們再次修改原來的XStreamTest02例子，將下面代碼

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

修改為

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

2、執行代碼

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<Phone> phones = new ArrayList<>(); phones.add(new Phone("小米手機", "小米手機的描述")); phones.add(new Phone("蘋果手機", "蘋果手機的描述")); Student student = new Student("張三", phones);  XStream xStream = new XStream();//需要XPP3庫 // 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<Phone> phones; }  @AllArgsConstructor @ToString class Phone { private String brand; private String description; }

3、執行結果

<xx.xx.xx.xx.Student name="張三"> <xx.xx.xx.xx.Phone> <brand>小米手機</brand> <description>小米手機的描述</description> </xx.xx.xx.xx.Phone> <xx.xx.xx.xx.Phone> <brand>蘋果手機</brand> <description>蘋果手機的描述</description> </xx.xx.xx.xx.Phone> </xx.xx.xx.xx.Student>

可以看到包名由io.github.xstream.test02替換為了xx.xx.xx.xx

九、XStream注解

1、前面的四、五、六、七、八步驟都是通過代碼操作的

//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同時也支持注解，使用注解會變得簡單也會達到相同的效果

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<Phone> phones = new ArrayList<>(); phones.add(new Phone("小米手機", "小米手機的描述")); phones.add(new Phone("蘋果手機", "蘋果手機的描述")); Student student = new Student("張三", phones, 20, true); XStream xStream = new XStream();//需要XPP3庫 //xStream.processAnnotations(new Class[]{Student.class}); xStream.autodetectAnnotations(true); //XML序列化 String xml = xStream.toXML(student); System.out.println(xml); } }  @AllArgsConstructor @ToString //別名注解 @XStreamAlias("student") class Student { @XStreamAlias("name") //把字段節點設置成屬性 @XStreamAsAttribute private String studentName; //省略集合根節點 @XStreamImplicit private List<Phone> phones; //隱藏字段 @XStreamOmitField private int age; //設置轉換器 @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、使用注解的話，需要XML序列化之前添加如下代碼

xStream.autodetectAnnotations(true);

或者

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

4、執行結果

<student name="張三"> <phone> <brand>小米手機</brand> <description>小米手機的描述</description> </phone> <phone> <brand>蘋果手機</brand> <description>蘋果手機的描述</description> </phone> <sex>男</sex> </student>

使用注解我們也可以看到也能達到相同的效果

注意：當使用XStream對象處理一個被注解的類型時，XStream對象也會處理所有與其相關的類型的注解信息，即該類型的父類、父接口、所有子類的注解。

十、XStream自定義轉換器

1、XStream自帶的轉換器

XStream內部有許多轉換器，用於JavaBean對象到XML或JSON之間的轉換。這些轉換器的詳細信息網址：http://x-stream.github.io/converters.html

2、使用自定義轉換器

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("張三",19); XStream xStream = new XStream(); //注冊轉換器 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; }

自定義轉換器

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 { //定義轉換器能轉換的JavaBean類型 @Override public boolean canConvert(Class type) { return type.equals(Student.class); }  //把對象序列化成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("年齡"); writer.setValue(student.getAge() + ""); writer.endNode(); writer.startNode("轉換器"); writer.setValue("自定義的轉換器"); writer.endNode(); }  //把XML或JSON反序列化成對象 @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、執行結果

<student>
  <姓名>張三</姓名>
  <年齡>19</年齡>
  <轉換器>自定義的轉換器</轉換器>
</student>
Security framework of XStream not initialized, XStream is probably vulnerable.
Student(name=張三, age=19)

4、常用的轉換器接口與抽象類

SingleValueConverter：單值轉換接口
AbstractSingleValueConverter：單值轉換抽象類
Converter：常規轉換器接口

十一、XStream對象流

1、對象輸出流

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庫 xStream.processAnnotations(Student.class); xStream.autodetectAnnotations(true); xStreamTest04.writeObject(xStream, path); }  //對象輸出流方法 public void writeObject(XStream xStream, String path) throws IOException { Student zs = new Student("張三", 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 //別名注解 @XStreamAlias("student") class Student { @XStreamAlias("name") //把字段節點設置成屬性 @XStreamAsAttribute private String studentName; private int age; }

2、在指定路徑中打開test.txt文件，查看執行結果

<object-stream> <student name="張三"> <age>20</age> </student> <student name="李四"> <age>21</age> </student> <student name="王五"> <age>22</age> </student> <string>totalStudent</string> <int>3</int> </object-stream>

注意：XStream對象流是通過標准java.io.ObjectOutputStream和java.io.ObjectInputStream對象。因為XML文檔只能有一個根節點，必須包裝在一個序列化的所有元素額外的根節點。這個根節點默認為<object-stream>上面的例子所示。

3、對象輸入流

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庫 xStream.processAnnotations(Student.class); xStream.autodetectAnnotations(true); xStreamTest04.readObject(xStream, path); }  //對象輸入流方法 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 //別名注解 @XStreamAlias("student") class Student { @XStreamAlias("name") //把字段節點設置成屬性 @XStreamAsAttribute private String studentName; private int age; }

4、執行結果

Student(studentName=張三, 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對象

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對象 public void saveObject(){ PersistenceStrategy strategy = new FilePersistenceStrategy(new File("F:\\")); List list = new XmlArrayList(strategy); list.add(new Student("張三",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、運行程序結果，在F磁盤的根路徑可以看到有三個文件:int@0.xml、int@1.xml、int@2.xml，每個對象都被序列化到XML文件里

3、讀取並刪除JavaBean對象

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(); } //讀取並刪除Java對象 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()); //刪除對象序列化文件 it.remove(); } } }  @ToString @AllArgsConstructor class Student { private String name; private int age; }

4、運行程序結果，可以看到把F磁盤的根路徑int@0.xml、int@1.xml、int@2.xml文件刪除了

Security framework of XStream not initialized, XStream is probably vulnerable.
Student(name=張三, 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("張三", 19); XStream xStream = new XStream(new JettisonMappedXmlDriver());//設置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("年齡") private int age; }

2、運行結果

{"人":{"姓名":"張三","年齡":19}}
Student(name=張三, age=19)
Security framework of XStream not initialized, XStream is probably vulnerable.

注意：XStream序列化JSON的重命名的方式與其序列化成XML的方式一樣！

3、去掉序列化JSON的根節點

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("張三", 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("年齡") private int age; }