XML 和 java对象相互转换

下面使用的是JDK自带的类，没有引用任何第三方jar包。

Unmarshaller 类使客户端应用程序能够将 XML 数据转换为 Java 内容对象树。

备注：marshal(序列化、排列、整理)

Marshaller 类使客户端应用程序能够将 Java 内容树转换回 XML 数据。

Java代码

package hb.jaxb;

public class Classroom {

private int id;

private String name;

private int grade;

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 int getGrade() {

return grade;

}

public void setGrade(int grade) {

this.grade = grade;

}

public Classroom(int id, String name, int grade) {

super();

this.id = id;

this.name = name;

this.grade = grade;

}

public Classroom() {

super();

}

}

Java代码

package hb.jaxb;

import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement

public class Student {

private int id;

private String name;

private int age;

private Classroom classroom;

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 int getAge() {

return age;

}

public void setAge(int age) {

this.age = age;

}

public Classroom getClassroom() {

return classroom;

}

public void setClassroom(Classroom classroom) {

this.classroom = classroom;

}

public Student(int id, String name, int age, Classroom classroom) {

super();

this.id = id;

this.name = name;

this.age = age;

this.classroom = classroom;

}

//无参够着函数一定需要，否则JXBContext无法正常解析。

public Student() {

super();

}

}

注意：

1、需要转换的model对象一定要添加@XmlRootElement注解，其里面的其他对象则不需要

2、需要转换的model对象一定要有不带参数的构造方法，包括该对象里面引用的对象。

Java代码

package hb.jaxb;

import java.io.StringReader;

import javax.xml.bind.JAXBContext;

import javax.xml.bind.JAXBException;

import javax.xml.bind.Marshaller;

import javax.xml.bind.Unmarshaller;

import org.junit.Test;

public class TestJaxb {

@Test

public void beanToXML() {

Classroom classroom = new Classroom(1, "软件工程", 4);

Student student = new Student(101, "张三", 22, classroom);

try {

JAXBContext context = JAXBContext.newInstance(Student.class);

Marshaller marshaller = context.createMarshaller();

marshaller.marshal(student, System.out);

} catch (JAXBException e) {

e.printStackTrace();

}

}

@Test

public void XMLStringToBean(){

String xmlStr = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?><student><age>22</age><classroom><grade>4</grade><id>1</id><name>软件工程</name></classroom><id>101</id><name>张三</name></student>";

try {

JAXBContext context = JAXBContext.newInstance(Student.class);

Unmarshaller unmarshaller = context.createUnmarshaller();

Student student = (Student)unmarshaller.unmarshal(new StringReader(xmlStr));

System.out.println(student.getAge());

System.out.println(student.getClassroom().getName());

} catch (JAXBException e) {

e.printStackTrace();

}

}

}

JAXB（Java Architecture for XML Binding) 是一个业界的标准，是一项可以根据XML Schema产生Java类的技术。该过程中，JAXB也提供了将XML实例文档反向生成Java对象树的方法，并能将Java对象树的内容重新写到XML实例文档。从另一方面来讲，JAXB提供了快速而简便的方法将XML模式绑定到Java表示，从而使得Java开发者在Java应用程序中能方便地结合XML数据和处理函数。

JAXBContext 类提供到 JAXB API 的客户端入口点。它提供了管理实现 JAXB 绑定框架操作所需的 XML/Java 绑定信息的抽象，这些操作包括：解组、编组和验证。

转载：http://hbiao68.iteye.com/blog/1958413#comments