JavaWeb学习笔记-XML-7

XPath

dom4j

快速定位
拥有强大的选择器

//利用xpath提取xml文档数据SAXReader reader = new SaxReader();Document document = reader.read("book.xml");String value = document.selectSingleNode("//作者").getText();System.out.println(value);

<?xml version="1.0" encoidng="UTF-8"?><!--xml文件user.xml--><users>    <user id="1" username="aa" password="123" email="[e-mail]"/>    <user id="2" username="bb" password="123" email="[e-mail]"/></users>

//查找xml文档中是否存在匹配的用户名与密码public static void main(Stirng[] args){    String userNamae = "xxx";    Stirng passWord = "123";    //检测是否存在匹配的用户名与密码    SAXReader reader = new SAXReader();    Document documnet = reader.read(new File("user.xml"));    Node node = (Node)documnet.selectSingleNode("//user[@username='"+userName+"' and @password='"+passWord+"']");    if(node==null){        System.out.println("用户名或密码错误");    }else{        System.out.println("登陆成功");    }}