我想获取标签之间的所有内容,但由于 urn: 命名空间,我不知道该怎么做。
<urn:ResponseStatus version="1.0" xmlns:urn="urn:camera-org">
<urn:requestURL>/CAMERA/Streaming/status</urn:requestURL>
<urn:statusCode>4</urn:statusCode>
<urn:statusString>Invalid Operation</urn:statusString>
<urn:id>0</urn:id>
</urn:ResponseStatus>
有什么想法吗?
最佳答案
- 简短回答:使用 XPath
local-name()
。像这样:xPathFactory.newXPath().compile("//*[local-name()='requestURL']/text()");
将返回/CAMERA/Streaming/状态
- 或者您可以实现一个映射命名空间名称和 URI 的
NamespaceContext
,并在查询之前将其设置在 XPath 对象上。 - 看看这个blog article ,更新:文章已下,可以在webarchive上看到
解决方案 1 示例:
XPath xpath = XPathFactory.newInstance().newXPath();
String responseStatus = xpath.evaluate("//*[local-name()='ResponseStatus']/text()", document);
System.out.println("-> " + responseStatus);
解决方案 2 示例:
// load the Document
Document document = ...;
NamespaceContext ctx = new NamespaceContext() {
public String getNamespaceURI(String prefix) {
return prefix.equals("urn") ? "urn:camera-org" : null;
}
public Iterator getPrefixes(String val) {
return null;
}
public String getPrefix(String uri) {
return null;
}
};
XPath xpath = XPathFactory.newInstance().newXPath();
xpath.setNamespaceContext(ctx);
String responseStatus = xpath.evaluate("//urn:ResponseStatus/text()", document);
System.out.println("-> " + responseStatus);
编辑
这是一个完整的例子,它正确地获取了元素:
String xml = "<urn:ResponseStatus version=\"1.0\" xmlns:urn=\"urn:camera-org\">\r\n" + //
"\r\n" + //
"<urn:requestURL>/CAMERA/Streaming/status</urn:requestURL>\r\n" + //
"<urn:statusCode>4</urn:statusCode>\r\n" + //
"<urn:statusString>Invalid Operation</urn:statusString>\r\n" + //
"<urn:id>0</urn:id>\r\n" + //
"\r\n" + //
"</urn:ResponseStatus>";
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
factory.setNamespaceAware(true);
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse(new java.io.ByteArrayInputStream(xml.getBytes()));
XPath xpath = XPathFactory.newInstance().newXPath();
xpath.setNamespaceContext(new NamespaceContext() {
public String getNamespaceURI(String prefix) {
return prefix.equals("urn") ? "urn:camera-org" : null;
}
public Iterator<?> getPrefixes(String val) {
return null;
}
public String getPrefix(String uri) {
return null;
}
});
XPathExpression expr = xpath.compile("//urn:ResponseStatus");
Object result = expr.evaluate(doc, XPathConstants.NODESET);
NodeList nodes = (NodeList) result;
for (int i = 0; i < nodes.getLength(); i++) {
Node currentItem = nodes.item(i);
System.out.println("found node -> " + currentItem.getLocalName() + " (namespace: " + currentItem.getNamespaceURI() + ")");
}
关于java - Java 中带有命名空间的 XPath,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/13702637/