java - 具有不同命名空间的 XML 可以深入了解所需的值

Question

我试图弄清楚如何从以下 XML 文件中获取 jxdm:ID 的值:

<?xml version="1.0" encoding="UTF-8" standalone="no" ?> 
<My:Message 
xmlns:Abcd="http://...." 
xmlns:box-1="http://...." 
xmlns:bulb="http://...."
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
xmlns:xsd="http://www.w3.org/2001/XMLSchema" 
xsi:schemaLocation="http://....stores.xsd">
<Abcd:StoreDataSection>
    <Abcd:DataSection>
        <Abcd:FirstStore>
            <box-1:Response>
                <box-1:DataSection>
                    <box-1:Release>
                        <box-1:Activity>
                            <bulb:Date>2017-04-29</bulb:Date>
                            <bulb:Store xsi:type="TPIR:Organization">
                                <bulb:StoreID>
                                    <bulb:ID>D79G2102</bulb:ID>
                                </bulb:StoreID>
                            </bulb:Store>
                        </box-1:Activity>
                    </box-1:Release>
                </box-1:DataSection>
            </box-1:Response>
        </Abcd:FirstStore>
    </Abcd:DataSection>
</Abcd:StoreDataSection>
</ My:Message>

我不断得到“null”作为节点的值

Node node = (Node) xPath.evaluate(expression, document, XPathConstants.NODE);

这是我当前的 Java 代码:

try {
    DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();
    DocumentBuilder builder = builderFactory.newDocumentBuilder();
    Document document = builder.parse(new File("c:/temp/testingNamespace.xml"));

    XPath xPath = XPathFactory.newInstance().newXPath();
    String expression = "//My/Message//Abcd/StoreDataSection/DataSection/FirstStore//box-1/Response/DataSection/Release/Activity//bulb/Store/StoreID/ID";
    Node node = (Node) xPath.evaluate(expression, document, XPathConstants.NODE);

    node.setTextContent("changed ID");

    Transformer transformer = TransformerFactory.newInstance().newTransformer();
    transformer.transform(new DOMSource(document), new StreamResult(new File("C:/temp/test-updated.xml")));
} catch (Exception e) {
    System.out.println(e.getMessage());
}

如何设置正确的 XPath 格式以便我获取该值并更改它？

更新1

所以是这样的吗？

String expression = "/My:Message/Abcd:StoreDataSection/Abcd:DataSection/Abcd:FirstStore/box-1:Response/box-1:DataSection/box-1:Release/box-1:Activity/bulb:Store/bulb:StoreID/bulb:ID";

Answer 1

问题是您应该通过前缀(如果您愿意)但以不同的方式访问 Node，例如，如果您想访问 StorID，例如://bulb:StoreID。

话又说回来，它仍然无法工作，因为您需要告诉 XPath 如何解析命名空间前缀。

您应该检查这个答案:How to query XML using namespaces in Java with XPath?有关如何实现和使用 NamespaceContext 的详细信息。

底线是您需要实现 javax.xml.namespace.NamespaceContext 并将其设置为 XPath。

        XPath xpath = XPathFactory.newInstance().newXPath();
        NamespaceContext context = new MyNamespaceContext();

        xpath.setNamespaceContext(context);