使用面向对象对XML进行解析：dom和dom4j的用法

这是一个比较简单的例子，主要是运用面向对象的思想，对XML文件进行解析，用dom和dom4j方法

<?xml version="1.0" encoding="utf-8"?>
<students>
    <student>
        <name>张三</name>
        <age>20</age>
        <school>北京大学</school>
    </student>
    <student>
        <name>李四</name>
        <age>18</age>
        <school>清华大学</school>
    </student>
</students>

代码如下：

学生对象类

package d20160624;

public class Student {
    private String name;
    private String age;
    private String school;
    
    public Student() {
    }

    public Student(String name, String age, String school) {
        this.name = name;
        this.age = age;
        this.school = school;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getAge() {
        return age;
    }

    public void setAge(String age) {
        this.age = age;
    }

    public String getSchool() {
        return school;
    }

    public void setSchool(String school) {
        this.school = school;
    }
    //打印学生信息
    public void showInfo(){
        System.out.println("姓名："+this.name+"
年纪："+this.age+"
学校："+this.school);
        System.out.println("***********");
    }
    
}

dom解析：

package d20160624;

import java.io.File;
import java.io.IOException;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

/*
 * 使用DOM解析student.xml，输出打印学生信息
 */
public class DomParseStudent {
    private Document document;
    private String name,age,school;
    

    //    生成dom树
    public void getDom(File file){
//        创建解析器工厂
        DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
        try {
//            创建解析器对象
            DocumentBuilder db=dbf.newDocumentBuilder();
//            解析XML文件得到DOM树
            this.document=db.parse(file);
        } catch (ParserConfigurationException e) {
            e.printStackTrace();
        } catch (SAXException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }


    }
//    解析XML
    public void showEle(){
        DomParseStudent dps=new DomParseStudent();
        NodeList students=document.getElementsByTagName("student");
        for(int i=0;i<students.getLength();i++){
            Element student=(Element) students.item(i);
            NodeList names=student.getElementsByTagName("name");
            for(int j=0;j<names.getLength();j++){
                Element name=(Element) names.item(j);
                this.name=name.getTextContent();
            }
            NodeList ages=student.getElementsByTagName("age");
            for(int k=0;k<ages.getLength();k++){
                Element age=(Element) ages.item(k);
                this.age=age.getTextContent();
            }
            NodeList schools=student.getElementsByTagName("school");
            for(int p=0;p<schools.getLength();p++){
                Element school=(Element) schools.item(p);
                this.school=school.getTextContent();
            }
            
            Student stu=new Student(name, age, school);
            stu.showInfo();
            
        }
    }
    
    public static void main(String[] args){
        DomParseStudent dps=new DomParseStudent();
        File file=new File("D:\Java_study\workspace\myeclipse\HomeWork\src\d20160624\student.xml");
        dps.getDom(file);
        dps.showEle();
    }
}

dom4j解析：

package d20160624;

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

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

/*
 * 使用dom4j解析student.xml，输出打印学生信息
 */
public class Dom4jStudent {
    private Document document;
    private String name,age,school;
//    生成dom树
    public void getDom(File file){
//        创建SAXReader
        SAXReader sax=new SAXReader();
        try {
//            读取xml文件,生成dom树
            this.document=sax.read(file);
        } catch (DocumentException e) {
            e.printStackTrace();
        }
    }
    
//    读取XML文件
    public void showXML(){
        Element root=document.getRootElement();
        List<Element> student=root.elements();
        for(Iterator<Element> stuit=student.iterator();stuit.hasNext();){
            Element stu=stuit.next();
            List<Element> names=stu.elements("name");
            for(Iterator<Element> name=names.iterator();name.hasNext();){
                Element nameel=name.next();
                this.name=nameel.getText();
            }
            List<Element> ages=stu.elements("age");
            for(Iterator<Element> age=ages.iterator();age.hasNext();){
                Element ageel=age.next();
                this.age=ageel.getText();
            }
            List<Element> schools=stu.elements("school");
            for(Iterator<Element> school=schools.iterator();school.hasNext();){
                Element schoolel=school.next();
                this.school=schoolel.getText();
            }
            Student stu1=new Student(name, age, school);
            stu1.showInfo();
        }
    }
    
    public static void main(String[] args){
        Dom4jStudent d4j=new Dom4jStudent();
        File file=new File("D:\Java_study\workspace\myeclipse\HomeWork\src\d20160624\student.xml");
        d4j.getDom(file);
        d4j.showXML();
    }
}

其实2种方式，都可以，都是各种包中类的方法的使用，会灵活运用就可以了！