DOM4J读取XML

Posted 2020-09-29 头痛不头痛

  实现读取XML元素和添加元素

package cn.test;

import java.io.FileOutputStream;
import java.io.OutputStreamWriter;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;
import org.junit.Test;

/**
 * 需要两个jar包
 * dom4j-1.6.1.jar－306 KB
 * jaxen-1.1-beta-6.jar
 * @author zy
 *
 */

public class Dom4jTest {
	
	@Test
	public void readXML(){
		String path = "D:/Temp/users.xml";
		//创建解析器
		SAXReader reader = new SAXReader();
		try {
			//得到document
			Document doc = reader.read(path);
			//通过xpath查询得到Element
			Element ele = (Element) doc.selectSingleNode(
					"//user[@username=‘scott‘]");
			//获取该元素的名为username的属性值
			String username = ele.attributeValue("username");
			String password = ele.attributeValue("password");
			System.out.println(username+","+password);
		} catch (DocumentException e) {
			e.printStackTrace();
		}
	}
	
	@Test
	public void writeXML(){
		String path = "D:/Temp/users.xml";
		//创建解析器
				SAXReader reader = new SAXReader();
				try {
					//得到document
					Document doc = reader.read(path);
					//得到根元素
					Element root = doc.getRootElement();
					//通过根元素创建新元素user
					Element userEle = root.addElement("user");
					//为userEle设置属性
					userEle.addAttribute("username","scott");
					userEle.addAttribute("password","tiger");
					//设置文档格式，使用\t缩进，使用换行
					OutputFormat format = new OutputFormat("\t",true);
					//删除原来已有的文档的缩进和换行
					format.setTrimText(true);
					//创建XMLWriter
					XMLWriter writer;
					try {
						 writer = new XMLWriter(
						  new OutputStreamWriter(
								  new FileOutputStream(path),"utf-8"),format);
					//保存document对象
						writer.write(doc);
						writer.close();
					} catch (Exception e) {
						e.printStackTrace();
					} 
				} catch (DocumentException e) {
					e.printStackTrace();
				}
	}

}

　　

xml

<?xml version="1.0" encoding="UTF-8"?>

<users>
	<user username="scott" password="tiger"/>
</users>