序列化反序列化--Xstream的使用

之前讲了fastjson的使用--将JavaBean与json对象之间互相转换。

该篇文章，教大家使用Xstream来实现XMl与JavaBean的转换。

第一步：

通过maven引入XStream的jar包。

  <!-- https://mvnrepository.com/artifact/com.thoughtworks.xstream/xstream -->
<dependency>
    <groupId>com.thoughtworks.xstream</groupId>
    <artifactId>xstream</artifactId>
    <version>1.3.1</version>
</dependency>

第二步：

准备一个需要序列化和反序列化的类：

注：

1.该类必须有无参的构造函数，否则报错：Cannot construct com.claire.jing.test0811.Student as it does not have a no-args constructor

2.该类 implements Serializable ，这个接口仅仅是标识作用，写上只是标识该类是可以被序列化和反序列化的。

public class Student implements Serializable {
    
    private int id;
    private String name;
    private String school;
    
    public Student() {
        // TODO Auto-generated constructor stub
    }
    public Student(int id, String name, String school) {
        super();
        this.id = id;
        this.name = name;
        this.school = school;
    }
    
    
    
    
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getSchool() {
        return school;
    }
    public void setSchool(String school) {
        this.school = school;
    }
    
    
    @Override
    public String toString() {
        return "Student [id=" + id + ", name=" + name + ", school=" + school + "]";
    }
    
    

}

第三步：使用XStream来实现该类的序列化和反序列

public class SerializeXml {
    public static void main(String[] args) {
        serializeToXml();
　　　　　System.out.println("**************************************");
        deserialize();
    }
    
    
    
    public static void serializeToXml() {
        FileOutputStream write = null;
        Student stu1 = new Student(10003, "claire", "hh");
        Student stu2 = new Student(10004, "leafly", "hh");
        
        Student[] students = {stu1,stu2};

        
        XStream xstream = new XStream();
        try {
　　　　　　　　//将文流怼到文件上
            write = new FileOutputStream("F:/myObjtoXml.txt");
　　　　　　　　//将学生对象序列化成Xml并通过流写入到文件中
            xstream.toXML(students, write);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        //将序列化结果输出
        System.out.println(xstream.toXML(students));
        
    }
    
    public static void deserialize() {
        FileInputStream reader;
        XStream xstream = new XStream();
        
        Student[] students=null;
        try {
            reader = new FileInputStream("F:/myObjtoXml.txt");
　　　　　　　　//将Xml文件反序列化为Student对象
            students=(Student[])xstream.fromXML(reader);
            if (students != null) {
                for (Student student : students) {
                    System.out.println(student);
                }
            }
            
        } catch (FileNotFoundException e) {
            
            e.printStackTrace();
        }
        
    }
}

上面程序的输出结果为：

<com.claire.jing.test0811.Student-array>
<com.claire.jing.test0811.Student>
<id>10003</id>
<name>claire</name>
<school>hh</school>
</com.claire.jing.test0811.Student>
<com.claire.jing.test0811.Student>
<id>10004</id>
<name>leafly</name>
<school>hh</school>
</com.claire.jing.test0811.Student>
</com.claire.jing.test0811.Student-array>
**************************************
Student [id=10003, name=claire, school=hh]
Student [id=10004, name=leafly, school=hh]

上面都是最简单的序列化和反序列化的格式：

1.当Xml中有属性的时候，如：

<student age="15">

使用上面的反序列化就会报错，此时只要加上：

xstream.useAttributeFor(Student.class, "age");

 

2.序列化出来的xml文件中，都带有包名，如果不想让其显示类全名，只要给该类起个别名即可：

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