Dom4j实体对象和xml之间相互转化

对象集合生成xml

student.java

import lombok.Data;

import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

/**
 * @author 作者：
 * @date 创建时间2021/6/15 13:51
 */
@Data
public class Student   {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private String id;

    private String name;

    private String number;

    private Integer age;

    private String gender;

    private String city;

    public Student(String id, String name, String number, Integer age, String gender, String city) {
        this.id = id;
        this.name = name;
        this.number = number;
        this.age = age;
        this.gender = gender;
        this.city = city;
    }

    public Student() {
    }

    @Override
    public String toString() {
        return "Student{" +
                "id='" + id + '\'' +
                ", name='" + name + '\'' +
                ", number='" + number + '\'' +
                ", age=" + age +
                ", gender='" + gender + '\'' +
                ", city='" + city + '\'' +
                '}';
    }
}

import org.dom4j.Document;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.XMLWriter;

import java.io.*;
import java.lang.reflect.Field;
import java.util.ArrayList;

/**
 * @author 作者：
 * @date 创建时间2021/6/15 14:04
 */
public class Dom4jEntityWriter {

    public static void main(String[] args) {
        ArrayList<Student> stuList = new ArrayList<>();
        stuList.add(new Student("1", "张三", "1001", 21, "男", "湖南"));
        stuList.add(new Student("2", "李四", "1002", 20, "男", "甘肃"));
        stuList.add(new Student("3", "王五", "1003", 22, "男", "湖南"));
        writeXml(stuList, Student.class);
    }

    /**
     * 写入xml
     *
     * @param stuList      集合数据
     * @param elementClass 对应的class
     */
    public static void writeXml(ArrayList stuList, Class elementClass) {
        //创建一个document
        Document document = DocumentHelper.createDocument();
        //增加根节点
        Element root = document.addElement(elementClass.getSimpleName() + "s");
        //循环student节点
        for (Object obj : stuList) {
            Element stuElement = root.addElement(elementClass.getSimpleName());
            try {
                //获取Student对象的所有属性
                Field[] fields = elementClass.getDeclaredFields();
                for (Field field : fields) {
                    field.setAccessible(true);
                    System.out.println("属性名：" + field.getName() + ",值" + field.get(obj));
                    //给student节点中添加student的子节点
                    stuElement.addElement(field.getName()).setText(field.get(obj).toString());
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }

        try {
            OutputFormat format = OutputFormat.createPrettyPrint();
            //将xml写入文件
            XMLWriter xmlWriter = new XMLWriter(new FileOutputStream(new File("students.xml")), format);
            xmlWriter.write(document);
            xmlWriter.close();
        } catch (Exception e) {
            e.printStackTrace();
        }

    }
}

生成一个Students.xml文件

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

<Students>
  <Student>
    <id>1</id>
    <name>张三</name>
    <number>1001</number>
    <age>21</age>
    <gender>男</gender>
    <city>湖南</city>
  </Student>
  <Student>
    <id>2</id>
    <name>李四</name>
    <number>1002</number>
    <age>20</age>
    <gender>男</gender>
    <city>甘肃</city>
  </Student>
  <Student>
    <id>3</id>
    <name>王五</name>
    <number>1003</number>
    <age>22</age>
    <gender>男</gender>
    <city>湖南</city>
  </Student>
</Students>

将xml转换为实体对象

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

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

/**
 * @author 作者：
 * @date 创建时间2021/6/15 14:49
 * 将xml转换为实体类
 */
public class Dom4jEntityReader {

    public static void main(String[] args) {
        getDocument(new File("Students.xml"));
    }

    private static void getDocument(File file) {
        try {
            ArrayList<Student> list = new ArrayList<>();
            SAXReader saxReader = new SAXReader();
            Document document = saxReader.read(file);
            Element rootElement = document.getRootElement();
            //枚举所有子节点
            for (Iterator i = rootElement.elementIterator(); i.hasNext(); ) {
                Element elementStudent = (Element) i.next();
                List<Attribute> attributes = elementStudent.attributes();
                for (Attribute attribute : attributes) {
                    System.out.println("属性名：" + attribute.getName() + "--属性值：" + attribute.getValue());
                }

                Iterator iterator = elementStudent.elementIterator();
                Student student = new Student();
                while (iterator.hasNext()) {
                    Element child = (Element) iterator.next();
                    System.out.println("节点名：" + child.getName() + "--节点值：" + child.getStringValue());
                    //将属性赋给student
                    if (child.getName().equals("id")) {
                        student.setId(child.getStringValue());
                    }
                    if (child.getName().equals("name")) {
                        student.setName(child.getStringValue());
                    }
                    if (child.getName().equals("number")){
                        student.setNumber(child.getStringValue());
                    }
                    if (child.getName().equals("age")){
                        student.setAge(Integer.valueOf(child.getStringValue()));
                    }
                    if (child.getName().equals("gender")){
                        student.setGender(child.getStringValue());
                    }
                    if (child.getName().equals("city")){
                        student.setCity(child.getStringValue());
                    }
                }
                list.add(student);
            }
            for (Student student : list) {
                System.out.println(student);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

运行结果

节点名：id--节点值：1
节点名：name--节点值：张三
节点名：number--节点值：1001
节点名：age--节点值：21
节点名：gender--节点值：男
节点名：city--节点值：湖南
节点名：id--节点值：2
节点名：name--节点值：李四
节点名：number--节点值：1002
节点名：age--节点值：20
节点名：gender--节点值：男
节点名：city--节点值：甘肃
节点名：id--节点值：3
节点名：name--节点值：王五
节点名：number--节点值：1003
节点名：age--节点值：22
节点名：gender--节点值：男
节点名：city--节点值：湖南
Student{id='1', name='张三', number='1001', age=21, gender='男', city='湖南'}
Student{id='2', name='李四', number='1002', age=20, gender='男', city='甘肃'}
Student{id='3', name='王五', number='1003', age=22, gender='男', city='湖南'}