JAXB中不使用annotation的示例

在JAXB中，其实不用annotation也是可以的，虽然比较麻烦，下面是一个例子：

package blog.defaults;

import java.util.List;

public class Customer {

    private String firstName;
    private String lastName;
    private List<PhoneNumber> phoneNumbers;

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public List<PhoneNumber> getPhoneNumbers() {
        return phoneNumbers;
    }

    public void setPhoneNumbers(List<PhoneNumber> phoneNumbers) {
        this.phoneNumbers = phoneNumbers;
    }

}

另外一个POJO

package blog.defaults;

public class PhoneNumber {

    private String foo;
    private String bar;

    public String getType() {
        return foo;
    }

    public void setType(String type) {
        this.foo = type;
    }

    public String getNumber() {
        return bar;
    }

    public void setNumber(String number) {
        this.bar = number;
    }

}

然后下面的是一个XML文件，先展示的是将xml文件反序列化为CUSTOMER类，

<?xml version="1.0" encoding="UTF-8"?>
<customer>
    <firstName>Jane</firstName>
    <lastName>Doe</lastName>
     <phoneNumbers>
         <number>555-1111</number>
         <type>work</type>
     </phoneNumbers>
     <phoneNumbers>
         <number>555-2222</number>
         <type>home</type>
     </phoneNumbers>
</customer>

主程序如下：

package blog.defaults;

import javax.xml.bind.*;
import javax.xml.namespace.QName;
import javax.xml.transform.stream.StreamSource;

public class Demo {

    public static void main(String[] args) throws Exception {
        JAXBContext jc = JAXBContext.newInstance(Customer.class);

        StreamSource xml = new StreamSource("src/blog/defaults/input.xml");
        Unmarshaller unmarshaller = jc.createUnmarshaller();
        JAXBElement<Customer> je1 = unmarshaller.unmarshal(xml, Customer.class);
        Customer customer = je1.getValue();

        JAXBElement<Customer> je2 = new JAXBElement<Customer>(new QName("customer"), Customer.class, customer);
        Marshaller marshaller = jc.createMarshaller();
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
        marshaller.marshal(je2, System.out);
     }

}

可以看到在Customer customer = je1.getValue();
这句之前，就是读入了xml文件，然后进行unmarshaller的操作，之后得到的是一个
JAXBElement的对象实例，然后通过getValue得到其Customer对象实例。然后
接下来的代码是将customer再重新序列化为xml了。