我在互联网上找到了一些 JAXB2 的示例，@XmlRegistry但是没有很好的深入教程来讨论使用@XmlRegistrywith的概念@XmlElementDecl，想知道它是否是一个一般没有太多探索的概念。
无论如何，这是我的问题，首先是一些示例类，我使用 JAXB 来解组 xml：
我试图使用 JAXB 解组的主要类 - Employee.java
package com.test.jaxb;
import java.util.List;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.annotation.XmlElementDecl;
import javax.xml.bind.annotation.XmlRegistry;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.namespace.QName;
import com.test.jaxb.dto.Address;
@XmlRootElement
public class Employee {
private int id;
private String name;
private String email;
private List<Address> addresses;
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 getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public List<Address> getAddresses() {
return addresses;
}
public void setAddresses(List<Address> addresses) {
this.addresses = addresses;
}
@SuppressWarnings("unused")
@XmlRegistry
public static class XMLObjectFactory {
@XmlElementDecl(scope = Employee.class, name= "id")
JAXBElement<String> createEmployeeId(String value) {
return new JAXBElement<String>(new QName("id"), String.class, "100");
}
@XmlElementDecl(scope = Employee.class, name= "name")
JAXBElement<String> createName(String value) {
return new JAXBElement<String>(new QName("name"), String.class, "Fake Name");
}
@XmlElementDecl(scope = Employee.class, name= "email")
JAXBElement<String> createEmail(String value) {
return new JAXBElement<String>(new QName("email"), String.class, value);
}
@XmlElementDecl(scope = Employee.class, name= "addresses")
JAXBElement<List> createAddresses(List value) {
return new JAXBElement<List>(new QName("addresses"), List.class, value);
}
}
}
子类 - Address.java
package com.test.jaxb.dto;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.annotation.XmlElementDecl;
import javax.xml.bind.annotation.XmlRegistry;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.namespace.QName;
import com.test.jaxb.Employee;
@XmlRootElement
public class Address {
private String addressLine1;
private String addressLine2;
private String addressLine3;
public String getAddressLine1() {
return addressLine1;
}
public void setAddressLine1(String addressLine1) {
this.addressLine1 = addressLine1;
}
public String getAddressLine2() {
return addressLine2;
}
public void setAddressLine2(String addressLine2) {
this.addressLine2 = addressLine2;
}
public String getAddressLine3() {
return addressLine3;
}
public void setAddressLine3(String addressLine3) {
this.addressLine3 = addressLine3;
}
@SuppressWarnings("unused")
@XmlRegistry
private static class XMLObjectFactory {
@XmlElementDecl(scope = Employee.class, name= "addressLine1")
JAXBElement<String> createAddressLine1(String value) {
return new JAXBElement<String>(new QName("addressLine1"), String.class, value);
}
@XmlElementDecl(scope = Employee.class, name= "addressLine2")
JAXBElement<String> createAddressLine2(String value) {
return new JAXBElement<String>(new QName("addressLine2"), String.class, value);
}
@XmlElementDecl(scope = Employee.class, name= "addressLine3")
JAXBElement<String> createAddressLine3(String value) {
return new JAXBElement<String>(new QName("addressLine3"), String.class, value);
}
}
}
要解组的 xml - employee.xml
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<employee>
<id>1</id>
<name>Vaishali</name>
<email>Vaishali@example.com</email>
<addresses>
<address>
<addressLine1>300</addressLine1>
<addressLine2>Mumbai</addressLine2>
<addressLine3>India</addressLine3>
</address>
<address>
<addressLine1>301</addressLine1>
<addressLine2>Pune</addressLine2>
<addressLine3>India</addressLine3>
</address>
</addresses>
</employee>
解组代码：
package com.test.jaxb;
import java.io.FileReader;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.Unmarshaller;
public class ObjectFactoryTest {
public static void main(String[] args) throws Exception {
FileReader reader = new FileReader("resources/employee.xml");
JAXBContext context = JAXBContext.newInstance(Employee.class);
Unmarshaller unmarshaller = context.createUnmarshaller();
Object obj = unmarshaller.unmarshal(reader);
System.out.println(obj);
}
}
当我使用上面的代码解组员工 xml 时，地址列表不会被填充。生成的员工对象只有一个空白的地址列表。我的映射有什么问题吗？
为了了解发生了什么并查看员工对象是否实际上是使用对象工厂创建的（具有 @XMLRegistry 注释），我更改了工厂方法中 id 和 name 的值，但这对输出没有影响，这告诉我 JAXB 实际上并没有使用 ObjectFactory，为什么？
我对这一切都错了吗？任何帮助，将不胜感激。