阿九说：Dom4j解析XML

  

　　1.先创建一个info.xml

　　

<phoneInfo>
    <brand name="小米">
        <type name="小米8"/>
        <type name="小米9"/>
        <type name="小米MIX"/>
    </brand>
    <brand name="iphone">
        <type name="iphone7"/>
        <type name="iphone8"/>
        <type name="iphoneX"/>
    </brand>
    <brand name="华为">
        <type name="华为P30"/>
        <type name="华为P20"/>
        <type name="华为P30 pro"/>
    </brand>
</phoneInfo>

　　

　　2.创建解析XML类Test(解析XML节点及属性的操作)

　　

package cn.kgc.dom4jtest;

import org.dom4j.Attribute;
import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;

import java.util.Iterator;

/**
 * xml解析
 */
public class Test {
    private SAXReader reader;

    public static void main(String[] args) throws Exception {
        SAXReader reader = new SAXReader();
        //读取xml文件，并生成document对象，现可通过document来操作文档
        Document document = reader.read("src/info.xml");
        //获取文档的根节点
        Element rootElement = document.getRootElement();
        System.out.println("根节点的名字是"+rootElement.getName());
        //获取子节点列表
        Iterator iterator = rootElement.elementIterator();
        while (iterator.hasNext()){
            //获取节点的名字
            Element firstChild = (Element) iterator.next();
            //System.out.println(firstChild.getName());
            //获取节点的属性值
            System.out.println(firstChild.attribute("name").getValue());
            //获取子节点的下一级节点
            Iterator iterator1 = firstChild.elementIterator();
            while (iterator1.hasNext()){
                Element element = (Element) iterator1.next();
                System.out.println("	"+element.attributeValue("name"));
            }
        }
    }
}

　　3.创建添加节点的类AddTest(添加节点及属性的操作)

　　

package cn.kgc.dom4jtest;

import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;

import java.io.File;
import java.io.FileOutputStream;
import java.io.OutputStream;

/**
 * 添加节点的操作
 */
public class AddTest1 {
    public static void main(String[] args) throws Exception {
        SAXReader reader=new SAXReader();
        Document document=reader.read("src/info.xml");
        //获取到根节点
        Element rootElement = document.getRootElement();
        //添加一个子节点
        Element newEle = rootElement.addElement("brand");
        //给当前节点添加属性
        newEle.addAttribute("name","魅族");
        Element type1 = newEle.addElement("type");
        type1.addAttribute("name","s16");
        OutputStream o=new FileOutputStream(new File("src/info.xml"));
        XMLWriter xmlWriter=new XMLWriter(o);
        xmlWriter.write(rootElement);
        xmlWriter.flush();
        xmlWriter.close();
    }
}

　　4.创建修改节点及属性的类UpdateTest(修改节点及属性的操作)

　　

package cn.kgc.dom4jtest;

import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;

import java.io.File;
import java.io.FileOutputStream;
import java.util.Iterator;

/**
 * 执行修改操作
 */
public class UpdateTest {
    public static void main(String[] args) throws Exception {
        SAXReader reader=new SAXReader();
        Document document=reader.read("src/info.xml");
        //获取根节点
        Element rootElement = document.getRootElement();
        Iterator iterator = rootElement.elementIterator();
        while (iterator.hasNext()){
            Element firstEle = (Element) iterator.next();
            System.out.println(firstEle.attributeValue("name"));
            if (firstEle.attributeValue("name").equals("魅族")){
                Iterator type = firstEle.elementIterator();
                while (type.hasNext()){
                    Element next = (Element) type.next();
                    if (next.attributeValue("name").equals("s16")){
                        next.addAttribute("name","16 pro");
                    }
                }
            }
        }
        XMLWriter xmlWriter=new XMLWriter(new FileOutputStream(new File("src/info.xml")));
        xmlWriter.write(rootElement);
        xmlWriter.flush();
        xmlWriter.close();
    }
}

　　5.创建删除节点及属性的类DelTest(删除节点及属性的操作)

　　

package cn.kgc.dom4jtest;

import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;

import java.io.File;
import java.io.FileOutputStream;
import java.util.Iterator;

/**
 * 执行操作
 */
public class DelTest {
    public static void main(String[] args) throws Exception {
        SAXReader saxReader=new SAXReader();
        Document document = saxReader.read("src/info.xml");
        Element rootElement = document.getRootElement();
        Iterator iterator = rootElement.elementIterator();
        while (iterator.hasNext()){
             Element element = (Element) iterator.next();
             if (element.attributeValue("name").equals("魅族")){
                //通过父节点删除子节点
                element.getParent().remove(element);
             }
        }
        XMLWriter writer=new XMLWriter(new FileOutputStream(new File("src/info.xml")));
        writer.write(rootElement);
        writer.flush();
        writer.close();
    }
}