JAXB 超类字段未反序列化答案

【问题标题】：JAXB super class field not being deserializedJAXB 超类字段未反序列化
【发布时间】：2018-02-11 21:48:38
【问题描述】：

我正在尝试将 xml 字符串反序列化为对象，但遇到了奇怪的问题。一切都按预期进行序列化，但是当反序列化源自父类的字段时，始终返回 null。

MyNffgDescriptor 是一个包含 VNFTypeReader 作为属性的类。除了从父类 (NamedEntityReaderImpl) 传递的 name 并返回 null 之外，所有字段都正确反序列化，VNFTypeReader 也是如此。

父类

package it.polito.dp2.NFV.sol3.client1.implementations;

import java.io.Serializable;

import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlElement;

import it.polito.dp2.NFV.NamedEntityReader;


@XmlAccessorType(XmlAccessType.NONE)
public class NamedEntityReaderImpl implements NamedEntityReader, Serializable {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    private String entityName;

    public NamedEntityReaderImpl() {
        this.entityName = "";
    }

    public NamedEntityReaderImpl(String name) {
        this.entityName = name;
    }

    @Override
    public String getName() {
        return this.entityName;
    }

}

儿童班

    package it.polito.dp2.NFV.sol3.client1.implementations;

import java.io.Serializable;

import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;

import it.polito.dp2.NFV.VNFTypeReader;

@XmlRootElement
@XmlAccessorType(XmlAccessType.FIELD)
public class VNFTypeReaderImpl extends NamedEntityReaderImpl implements Serializable,VNFTypeReader {
    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    @XmlElement
    private int requiredMemory;

    @XmlElement
    private int requiredStorage;

    @XmlElement
    private it.polito.dp2.NFV.FunctionalType funcType;

    public VNFTypeReaderImpl() {
        super(null);
        this.requiredMemory = 0;
        this.requiredStorage = 0;
        this.funcType = null;
    }

    public VNFTypeReaderImpl(VNFTypeReader reader) {
        super(reader.getName());
        this.requiredMemory = reader.getRequiredMemory();
        this.requiredStorage = reader.getRequiredStorage();
        this.funcType = reader.getFunctionalType();
    }

    @Override
    public int getRequiredMemory() {
        return this.requiredMemory;
    }

    @Override
    public int getRequiredStorage() {
        return this.requiredStorage;
    }

    @Override
    public it.polito.dp2.NFV.FunctionalType getFunctionalType() {
        return this.funcType;
    }

    @Override
    @XmlElement(name="name", required=true)
    public String getName() {
        return super.getName();
    }

}

这是我试图反序列化的 xml 字符串示例：

<?xml version="1.0" encoding="UTF-8"?>
<myNffgDescriptor>
   <nodeList id="0">
      <funcReader>
         <requiredMemory>620</requiredMemory>
         <requiredStorage>100</requiredStorage>
         <funcType>WEB_SERVER</funcType>
         <name>WEBSERVERt</name>
      </funcReader>
      <hostName>H3</hostName>
      <linksList source="0" destination="10" />
      <linksList source="0" destination="11" />
      <linksList source="0" destination="8" />
   </nodeList>
</myNffgDescriptor>

解组的地方：

    jaxbContext = JAXBContext.newInstance(MyNffgDescriptor.class);
    unmarshaller = jaxbContext.createUnmarshaller();
    StringReader reader = new StringReader(nffg);
    MyNffgDescriptor nffgDesc = (MyNffgDescriptor) unmarshaller.unmarshal(reader);

【问题讨论】：

标签： java xml serialization jaxb

【解决方案1】：

将父级上的 XmlAccessType.NONE 更改为 XmlAccessType.FIELD 类 NamedEntityReaderImpl。

您也可以在 NamedEntityReaderImpl 类的字段上方添加一个注释：

@XmlElement(name= "name")
private String entityName;

做任何改变（或两者都做），它会工作

【讨论】：