XPath in Java: A Complete Guide

In Java, you can utilize classes from the javax.xml.xpath package to execute XPath expressions. Below are the general steps for using XPath.

1. Create an XPath object.

XPathFactory xPathFactory = XPathFactory.newInstance();
XPath xPath = xPathFactory.newXPath();

1. Compile the XPath expression.

XPathExpression xpathExpr = xPath.compile("XPath表达式");

1. Use XPath expressions to query nodes in an XML document.

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse(new File("xml文件路径"));
NodeList nodeList = (NodeList) xpathExpr.evaluate(doc, XPathConstants.NODESET);

1. Iterate through and process the query results.

for (int i = 0; i < nodeList.getLength(); i++) {
    Node node = nodeList.item(i);
    // 处理每个节点
}

The above is a general method for querying XML documents in Java using XPath, which can be further expanded and processed according to specific requirements.