jaxb2实例以及和XStream的比较
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Calendar;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
public class JAXB2Tester {
public static void main(String[] args) throws JAXBException,IOException {
JAXBContext context = JAXBContext.newInstance(Person.class);
//下面代码演示将对象转变为xml
Marshaller m = context.createMarshaller();
Address address = new Address("China","Beijing","Beijing","ShangDi West","100080");
Person p = new Person(Calendar.getInstance(),"JAXB2",address,Gender.MALE,"SW");
FileWriter fw = new FileWriter("person.xml");
m.marshal(p,fw);
//下面代码演示将上面生成的xml转换为对象
FileReader fr = new FileReader("person.xml");
Unmarshaller um = context.createUnmarshaller();
Person p2 = (Person)um.unmarshal(fr);
System.out.println("Country:"+p2.getAddress().getCountry());
}
}
@XmlRootElement//表示person是一个根元素
class Person {
@XmlElement
Calendar birthDay; //birthday将作为person的子元素
@XmlAttribute
String name; //name将作为person的的一个属性
public Address getAddress() {
return address;
}
@XmlElement
Address address; //address将作为person的子元素
@XmlElement
Gender gender; //gender将作为person的子元素
@XmlElement
String job; //job将作为person的子元素
public Person(){
}
public Person(Calendar birthDay, String name, Address address, Gender gender, String job) {
this.birthDay = birthDay;
this.name = name;
this.address = address;
this.gender = gender;
this.job = job;
}
}
enum Gender{
MALE(true),
FEMALE (false);
private boolean value;
Gender(boolean _value){
value = _value;
}
}
class Address {
@XmlAttribute
String country;
@XmlElement
String state;
@XmlElement
String city;
@XmlElement
String street;
String zipcode; //由于没有添加@XmlElement,所以该元素不会出现在输出的xml中
public Address() {
}
public Address(String country, String state, String city, String street, String zipcode) {
this.country = country;
this.state = state;
this.city = city;
this.street = street;
this.zipcode = zipcode;
}
public String getCountry() {
return country;
}
}
运行该程序，我们会得到一个person.xml的文件，如下：
<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<person name="JAXB2">
<birthDay>2006-12-28T08:49:27.203+00:00</birthDay>
<address country="China">
<state>Beijing</state>
<city>Beijing</city>
<street>ShangDi West</street>
</address>
<gender>MALE</gender>
<job>SW</job>
</person>
控制台会输出
Country:China
注意：改功能也可用xStream加注释实现，xStream的jar包需要1.3或者以上。
jaxb2和xstream的区别：
jaxb2如果没有加@XmlElement等注释，是不会写入到xml中的，但是xstream不会
xstream没有加上注释，默认以属性名称写入子级的元素中
XStream还可以将bean转为json，功能比较强悍，个人建议使用xstream