从封送对象构造org.w3c.dom.document

Question

public Document serialise() throws Exception {
    MyClass myObjectToMarshall = this.getObjectToMarshall();
    JAXBContext jc = JAXBContext.newInstance(MyClass.class);
    Marshaller m = jc.createMarshaller();
    m.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
    m.setProperty(Marshaller.JAXB_ENCODING, "UTF-8");
    m.marshal(myObjectToMarshall , System.out);
    StringWriter xml = new StringWriter();
    m.marshal(myObjectToMarshall , xml);
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    factory.setNamespaceAware(true);
    DocumentBuilder builder = factory.newDocumentBuilder();
    return builder.parse(new InputSource(new StringReader(xml.toString())));
}

<myObjectToMarshall >
    <id>15</id>
    <code>MY_CODE</code>
    <label>MY_LABEL</label>
    <date>2015-09-15+02:00</date>
</myObjectToMarshall >

我猜myObjectToMarshall的编组已经正确完成。

但是，当我使用IntelliJ,builder.parse（new InputSource（new StringReader(xml.tostring()))))调试最后一条指令时，我得到一个空文档:[#Document:null]

是否有其他属性可设置？

Answer 1

你的文件没问题。

实现toString()方法以返回“[”+getnodeName()+“：”+getnodeValue()+“]”。文档的nodename是#document，文档的nodeValue是null。参见节点的javadoc。

如果需要DOM文档，不要将其编入字符串中，然后解析文本。直接编组到DOM树中即可：

public Document serialise() throws Exception {
    MyClass myObjectToMarshall = this.getObjectToMarshall();
    JAXBContext jc = JAXBContext.newInstance(MyClass.class);
    DOMResult domResult = new DOMResult();
    jc.createMarshaller().marshal(myObjectToMarshall, domResult);
    return (Document)domResult.getNode();
}