Java Opensaml解组器提供Opensaml本地部分的消息不能为；空"；创建QName异常时

我正在使用Spring SAML，从IDP响应我接收issuer作为属性ID，因此我希望在Spring SAML中接收后更改响应，因此我已重写了方法unmarshall，该方法将解析消息并为此更改xml元素。在执行此操作时，如果我在解析后直接使用元素来解组，则它会工作，但如果我执行dom操作，则会出现以下异常。我不明白为什么它在第一个代码中抛出异常，但在下面附加的第二个代码中却没有。如何使其工作而无需再次转换为字符串并获取dom对象

Exception in thread "main" java.lang.IllegalArgumentException: local part cannot be "null" when creating a QName
    at java.xml/javax.xml.namespace.QName.<init>(QName.java:185)
    at java.xml/javax.xml.namespace.QName.<init>(QName.java:129)
    at org.opensaml.xml.util.XMLHelper.constructQName(XMLHelper.java:433)
    at org.opensaml.xml.util.XMLHelper.getNodeQName(XMLHelper.java:171)
    at org.opensaml.xml.io.UnmarshallerFactory.getUnmarshaller(UnmarshallerFactory.java:81)
    at org.opensaml.xml.io.AbstractXMLObjectUnmarshaller.unmarshallChildElement(AbstractXMLObjectUnmarshaller.java:334)
    at org.opensaml.xml.io.AbstractXMLObjectUnmarshaller.unmarshall(AbstractXMLObjectUnmarshaller.java:127)
    at org.opensaml.xml.io.AbstractXMLObjectUnmarshaller.unmarshallChildElement(AbstractXMLObjectUnmarshaller.java:355)
    at org.opensaml.xml.io.AbstractXMLObjectUnmarshaller.unmarshall(AbstractXMLObjectUnmarshaller.java:127)
    at org.opensaml.ws.message.decoder.BaseMessageDecoder.unmarshallMessage(unmarshallMessage.java:208)

但是对于下面的代码，它工作得很好，因为在这里我再次转换为string并创建了输入流，然后获得了传递用于解组的dom

protected XMLObject unmarshallMessage(InputStream messageStream) throws MessageDecodingException {
     log.debug("Parsing message stream into DOM document");

     try {
         Document messageDoc = parserPool.parse(messageStream);
         Element messageElem = messageDoc.getDocumentElement();
         Element elementsByTagName = (Element) messageElem.getElementsByTagName("saml2:Assertion").item(0);
         Element issuer = messageDoc.createElement("saml2:Issuer");
         issuer.setTextContent("emIDAM");
         issuer.setAttribute("Format", "urn:oasis:names:tc:SAML:2.0:nameid-format:entity");

         //converting again to string and getting dom
         String xml = XMLHelper.nodeToString(messageElem);
         messageStream = new ByteArrayInputStream(xml.getBytes());
         messageDoc = parserPool.parse(messageStream);
         messageElem = messageDoc.getDocumentElement();


         log.debug("Unmarshalling message DOM");
         Unmarshaller unmarshaller = Configuration.getUnmarshallerFactory().getUnmarshaller(messageElem);
         if (unmarshaller == null) {
             log.debug("Unable to unmarshall message, no unmarshaller registered for message element "
                     + XMLHelper.getNodeQName(messageElem));
             throw new MessageDecodingException(
                     "Unable to unmarshall message, no unmarshaller registered for message element "
                             + XMLHelper.getNodeQName(messageElem));
         }
         XMLObject message = unmarshaller.unmarshall(messageElem);

         return message;
     } catch (XMLParserException e) {
         log.error("Encountered error parsing message into its DOM representation", e);
         throw new MessageDecodingException("Encountered error parsing message into its DOM representation", e);
     } catch (UnmarshallingException e) {
         log.error("Encountered error unmarshalling message from its DOM representation", e);
         throw new MessageDecodingException("Encountered error unmarshalling message from its DOM representation", e);
     }
     catch (Exception e) {
         log.warn("Encountered error unmarshalling message from its DOM representation --->", e);
         throw new MessageDecodingException("Encountered error unmarshalling message from its DOM representation", e);
     }
 }

---

您的问题可能与解析器配置有关，可能未配置为命名空间感知

请在初始化

parserPool

时使用类似于以下代码的代码：

DocumentBuilderFactory DocumentBuilderFactory=DocumentBuilderFactory.newInstance（）；
documentBuilderFactory.setNamespaceAware（true）；
DocumentBuilder parserPool=documentBuilderFactory.newDocumentBuilder（）；

我的猜测是，第二个测试成功运行是因为在引擎盖下

XMLHelper

正在使用，而后者反过来使用

LSSerializer

执行实际的XML序列化。由于解析器被声明为非名称空间感知，因此产生的XML输出和相应的解析的

文档

将不包含名称空间信息，或者至少，它包含的信息的方式使

解组器随后执行的解析过程认为是适当的

此外，请注意，问题可能与您创建新
元素的方式有关，因为您没有提供名称空间信息：当您使用
createElement
时，生成的
元素将不包含
localName
，
前缀
，或者
namespaceURI
，都设置为
null
。请改为尝试以下代码：

documentmessagedoc=parserPool.parse（messageStream）；
Element messageElem=messageDoc.getDocumentElement（）；
元素assertionElem=（元素）messageElem.getElementsByTagName（“saml2:Assertion”）.item（0）；
Element-issuerElement=messageDoc.createElements（“urn:oasis:names:tc:SAML:2.0:assertion”，“saml2:Issuer”）；
Attr formatAttr=messageDoc.createAttributeNS（“urn:oasis:names:tc:SAML:2.0:assertion”，“saml2:Format”）；
setNodeValue（“urn:oasis:names:tc:SAML:2.0:nameid格式：entity”）；
setAttributeNode（formatAttr）；
Text Text=messageDoc.createTextNode（“emIDAM”）；
issuerElement.appendChild（文本）；
assertionElem.appendChild（issuerElement）；
@ashok您是否能够测试建议的方法？
protected XMLObject unmarshallMessage(InputStream messageStream) throws MessageDecodingException {
     log.debug("Parsing message stream into DOM document");

     try {
         Document messageDoc = parserPool.parse(messageStream);
         Element messageElem = messageDoc.getDocumentElement();
         Element elementsByTagName = (Element) messageElem.getElementsByTagName("saml2:Assertion").item(0);
         Element issuer = messageDoc.createElement("saml2:Issuer");
         issuer.setTextContent("emIDAM");
         issuer.setAttribute("Format", "urn:oasis:names:tc:SAML:2.0:nameid-format:entity");

         //converting again to string and getting dom
         String xml = XMLHelper.nodeToString(messageElem);
         messageStream = new ByteArrayInputStream(xml.getBytes());
         messageDoc = parserPool.parse(messageStream);
         messageElem = messageDoc.getDocumentElement();


         log.debug("Unmarshalling message DOM");
         Unmarshaller unmarshaller = Configuration.getUnmarshallerFactory().getUnmarshaller(messageElem);
         if (unmarshaller == null) {
             log.debug("Unable to unmarshall message, no unmarshaller registered for message element "
                     + XMLHelper.getNodeQName(messageElem));
             throw new MessageDecodingException(
                     "Unable to unmarshall message, no unmarshaller registered for message element "
                             + XMLHelper.getNodeQName(messageElem));
         }
         XMLObject message = unmarshaller.unmarshall(messageElem);

         return message;
     } catch (XMLParserException e) {
         log.error("Encountered error parsing message into its DOM representation", e);
         throw new MessageDecodingException("Encountered error parsing message into its DOM representation", e);
     } catch (UnmarshallingException e) {
         log.error("Encountered error unmarshalling message from its DOM representation", e);
         throw new MessageDecodingException("Encountered error unmarshalling message from its DOM representation", e);
     }
     catch (Exception e) {
         log.warn("Encountered error unmarshalling message from its DOM representation --->", e);
         throw new MessageDecodingException("Encountered error unmarshalling message from its DOM representation", e);
     }
 }