JAXB抽象类和XmlID / XmlIDREF

Question

好。 我是JAXB的新手，我的ID在抽象类中的XmlID和XmlIDREF遇到了一些麻烦。

这是我的问题：

抽象类

@XmlAccessorType(XmlAccessType.FIELD)
@XmlSeeAlso(EntityImpl.class)
public abstract class AbstractEntity {

    @XmlID
    private String id;

    public AbstractEntity() {
        this.id = generateStringId();
    }


    private static String generateStringId() {
        return "urn:uuid:" + UUID.randomUUID().toString();
    }
}

实施班

@XmlAccessorType(XmlAccessType.FIELD)
public class EntityImpl extends AbstractEntity {

    private String variabel_l = "1";
    private String variabel_2 = "2";
    private String variabel_3 = "3";
    private String variabel_4 = "4";
}

一些课

此类包含一个AbstractEntity，在本示例中为String。

@XmlAccessorType(XmlAccessType.FIELD)
public class SomeClass {

    @XmlIDREF
    private AbstractEntity ae;
    private String status;

    private SomeClass() {
    }

    public SomeClass(AbstractEntity ae, String status) {
        this.ae= ae;
        this.status = status;
    }

}

根

此类包含两个列表，一个列表包含“ SomeClass”的实例，一个列表包含“ EntityImpl”的实例

@XmlAccessorType(XmlAccessType.FIELD)
@XmlRootElement
public class Root {

    @XmlElementWrapper
    @XmlElement(name = "result")
    private List<SomeClass> someClassList = new ArrayList<>();


    @XmlElementWrapper
    @XmlElement(name = "entityImpl")
    private List<EntityImpl> entityImplList = new ArrayList<>();

    public void addResult(SomeClass someClass) {
        this.someClassList.add(someClass);
    }

    public void addEntityImpl(EntityImpl EntityImpl) {
        this.entityImplList.add(EntityImpl);
    }

演示代码

将impl添加到res，并且将res和impl都添加到其在root上的相应列表。

public static void main(String[] args) throws JAXBException {
    Root root = new Root();
    EntityImpl impl = new EntityImpl();

    SomeClass res = new SomeClass(impl, "something");
    root.addEntityImpl(impl);
    root.addResult(res);


    JAXBContext JAXB_CONTEXT;
    JAXB_CONTEXT = JAXBContext.newInstance(Root.class);

    StringWriter writer = new StringWriter();
    JAXB_CONTEXT.createMarshaller().marshal(root, writer);
    System.out.println(writer.getBuffer().toString());


    }

我想要的结果是对SomeClass实体中的impl的ID的引用，但是结果是这样的：

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<root>
    <someClassList>
        <result>
            <ae xsi:type="entityImpl" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                <id>urn:uuid:b8a4c0e4-330d-4ed7-9b68-1517d2eb4c2a</id>
                <variabel_l>1</variabel_l>
                <variabel_2>2</variabel_2>
                <variabel_3>3</variabel_3>
                <variabel_4>4</variabel_4>
                <variabel_5>5</variabel_5>
            </ae>
            <status>something</status>
        </result>
    </someClassList>
    <entityImplList>
        <entityImpl>
            <id>urn:uuid:b8a4c0e4-330d-4ed7-9b68-1517d2eb4c2a</id>
            <variabel_l>1</variabel_l>
            <variabel_2>2</variabel_2>
            <variabel_3>3</variabel_3>
            <variabel_4>4</variabel_4>
            <variabel_5>5</variabel_5>
        </entityImpl>
    </entityImplList>
</root>

如果我将@XmlIDREF移到根实体中的entityImplList，则引用工作正常，我得到以下信息：

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<root>
    <someClassList>
        <result>
            <ae xsi:type="entityImpl" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                <id>urn:uuid:46d0681f-4ec6-49ac-8c22-4954eaa5c680</id>
                <variabel_l>1</variabel_l>
                <variabel_2>2</variabel_2>
                <variabel_3>3</variabel_3>
                <variabel_4>4</variabel_4>
                <variabel_5>5</variabel_5>
            </ae>
            <status>something</status>
        </result>
    </someClassList>
    <entityImplList>
        <entityImpl>urn:uuid:46d0681f-4ec6-49ac-8c22-4954eaa5c680</entityImpl>
    </entityImplList>
</root>

当REF位于“ SomeClass”中时，是否可以使XmlID / XmlIDREF正常工作？
有任何想法吗？

Answer 1

当我完全按照问题的要求运行代码时，我得到以下信息，这不是输出的结果吗？

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<root>
    <someClassList>
        <result>
            <ae>urn:uuid:b34f3b9e-1086-4dfc-852f-4bc55b5d5a6e</ae>
            <status>something</status>
        </result>
    </someClassList>
    <entityImplList>
        <entityImpl>
            <id>urn:uuid:b34f3b9e-1086-4dfc-852f-4bc55b5d5a6e</id>
            <variabel_l>1</variabel_l>
            <variabel_2>2</variabel_2>
            <variabel_3>3</variabel_3>
            <variabel_4>4</variabel_4>
        </entityImpl>
    </entityImplList>
</root>

UPDATE

根据我本人和ØrjanJohansen的调查，在Windows的JDK 1.7.0_21中包含的JAXB的实现中似乎与此使用案例有关。 该用例在Mac的JDK 1.7.0_21和Windows的jdk1.6.0_45中正常工作。 当将EclipseLink MOXy用作JAXB（JSR-222）提供程序时，该用例也可以正常工作。