我正在尝试通过XPath设置节点值。我有以下但它似乎没有改变实际的文件值。
XPathFactory factory = XPathFactory.newInstance();
XPath xPath = factory.newXPath();
xPathExpression = "//test";
xPathValue= "111";
NodeList nodes = (NodeList) xPath.evaluate(xPathExpression, new InputSource(new FileReader(fileName)), XPathConstants.NODESET);
for (int k = 0; i < nodes.getLength(); i++)
{
System.out.println(nodes.item(k).getTextContent()); // Prints original value
nodes.item(k).setTextContent(xPathValue);
System.out.println(nodes.item(k).getTextContent()); // Prints 111 after
}
但该节点的文件内容保持不变。
如何设置该节点的值?
由于
答案 0 :(得分:2)
您只是更改内存中的值,而不是文件本身。您需要将修改后的文档写回文件:
Source source = new DOMSource(doc);
Result result = new StreamResult(new File(fileName));
Transformer xformer;
try {
xformer = TransformerFactory.newInstance().newTransformer();
xformer.transform(source, result);
} catch (TransformerConfigurationException e) {
// TODO Auto-generated catch block
} catch (TransformerFactoryConfigurationError e) {
// TODO Auto-generated catch block
} catch (TransformerException e) {
// TODO Auto-generated catch block
}
这些课程都来自javax.xml.transform.*
。
(当然,您需要保存对文档的引用,以便您可以回写它(即您将无法继续将其直接传递到evaluate
))。< / p>