使用XPATH java提取XML嵌套内容

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathFactory;

public class XPathExample {
    public static void main(String[] args) {
        try {
            // 创建DocumentBuilder对象
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = factory.newDocumentBuilder();

            // 解析XML文档并生成Document对象
            Document document = builder.parse("example.xml");

            // 创建XPath对象
            XPathFactory xpathFactory = XPathFactory.newInstance();
            XPath xpath = xpathFactory.newXPath();

            // 编译XPath表达式
            XPathExpression expr = xpath.compile("//book/title");

            // 执行XPath查询并返回结果
            NodeList nodeList = (NodeList) expr.evaluate(document, XPathConstants.NODESET);

            // 处理查询结果
            for (int i = 0; i < nodeList.getLength(); i++) {
                System.out.println(nodeList.item(i).getTextContent());
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}