XML DOM解析XML文件

采用DOM解析student.xml文件，将解析的每组数据保存在Student对象中，然后将Student对象添加到List集合。

注：解析器读入整个文档，然后构建一个驻留内存的树结构，使用 DOM 接口来操作这个树结构。

一、解析的XML文件（student.xml）

<?xml version="1.0" encoding="utf-8" ?><!--xml文档声明--><!--DTD约束--><!DOCTYPE class [        <!ELEMENT student (name,age,sex,height)>        <!ELEMENT name (#PCDATA)>        <!ELEMENT age (#PCDATA)>        <!ELEMENT sex (#PCDATA)>        <!ELEMENT height (#PCDATA)>        ]><!--只能有一个根标签--><class>    <!--设置属性-->    <student id="1" user="lisi">        <name>李四</name>        <age>18</age>        <sex>男</sex>        <height>182</height>    </student>    <student id="2" user="wangwu">        <name>王五</name>        <age>19</age>        <sex>男</sex>        <height>172</height>    </student></class>

二、解析代码

package com.xml.main;import org.w3c.dom.*;import org.xml.sax.SAXException;import javax.xml.parsers.DocumentBuilder;import javax.xml.parsers.DocumentBuilderFactory;import javax.xml.parsers.ParserConfigurationException;import java.io.File;import java.io.IOException;import java.util.ArrayList;public class DOMParseMain {    public static void main(String[] args) {        try {//            使用List存储解析到的学生信息            ArrayList<Student> list = new ArrayList<>();            //DOM解析的步骤            //步骤一：创建DOM解析工厂            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();            //步骤二：通过解析工厂 创建一个XML文档解析者            DocumentBuilder documentBuilder = factory.newDocumentBuilder();            //步骤三： 解析指定XML文件            Document document = documentBuilder.parse(new File("student.xml"));            //开始解析            Element documentElement = document.getDocumentElement();            //获取根元素节点下所有的节点(包含此节点的所有子节点，如：元素节点，文本节点，注释节点，空格换行等)            NodeList childNodes = documentElement.getChildNodes();            for (int i = 0; i < childNodes.getLength(); i++) {                Node item = childNodes.item(i);                Student student = new Student();//                只获取元素节点并且节点名称为student                if (item.getNodeType() == Node.ELEMENT_NODE && "student".equals(item.getNodeName())) {                    NamedNodeMap attributes = item.getAttributes();//得到Student所有的属性                    Node id = attributes.getNamedItem("id");//获取id节点                    String idValue = id.getNodeValue();//获取id的属性值                    Node user = attributes.getNamedItem("user");//获取user节点                    String userValue = user.getNodeValue();//获取user 属性值                    //添加信息到student对象中                    student.setId(Integer.parseInt(idValue));                    student.setUser(userValue);                    //遍历student节点下面的子节点                    NodeList childNodes1 = item.getChildNodes();                    for (int j = 0; j < childNodes1.getLength(); j++) {                        Node item1 = childNodes1.item(j);//                        获取元素节点                        if (item1.getNodeType() == Node.ELEMENT_NODE) {                            switch (item1.getNodeName()) {                                case "name":                                    String nameValue = item1.getFirstChild().getNodeValue();                                    student.setName(nameValue);                                    break;                                case "height":                                    String heightValue = item1.getFirstChild().getNodeValue();                                    student.setHeight(Double.parseDouble(heightValue));                                    break;                                case "age":                                    String ageValue = item1.getFirstChild().getNodeValue();                                    student.setAge(Integer.parseInt(ageValue));                                    break;                                case "sex":                                    String sexValue = item1.getFirstChild().getNodeValue();                                    student.setSex(sexValue);                                    break;                            }                        }                    }                    list.add(student);                }            }//遍历List            for (Student s : list) {                System.out.println(s.toString());            }        } catch (ParserConfigurationException e) {            e.printStackTrace();        } catch (SAXException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        } finally {        }    }}

 三、Student.java

package com.xml.main;public class Student {    private int id;    private String user;    private String name;    private String sex;    private int age;    private double height;    public Student() {    }    public Student(int id, String user, String name, String sex, int age, double height) {        this.id = id;        this.user = user;        this.name = name;        this.sex = sex;        this.age = age;        this.height = height;    }    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getUser() {        return user;    }    public void setUser(String user) {        this.user = user;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public String getSex() {        return sex;    }    public void setSex(String sex) {        this.sex = sex;    }    public int getAge() {        return age;    }    public void setAge(int age) {        this.age = age;    }    public double getHeight() {        return height;    }    public void setHeight(double height) {        this.height = height;    }    @Override    public String toString() {        return "Student{" +                "id=" + id +                ", user='" + user + '\'' +                ", name='" + name + '\'' +                ", sex='" + sex + '\'' +                ", age=" + age +                ", height=" + height +                '}';    }}

四、解析结果