<dependency>

            <groupId>dom4j</groupId>

            <artifactId>dom4j</artifactId>

            <version>1.6.1</version>

        </dependency>

        <dependency>

            <groupId>com.alibaba</groupId>

            <artifactId>fastjson</artifactId>

            <version>1.2.56</version>

        </dependency>

        <dependency>

            <groupId>commons-io</groupId>

            <artifactId>commons-io</artifactId>

            <version>2.6</version>

        </dependency>

package javax.utils;

import java.io.File;

import java.io.IOException;

import java.io.StringReader;

import java.io.StringWriter;

import java.net.URL;

import java.nio.file.Paths;

import org.apache.commons.io.FileUtils;

import org.apache.commons.io.IOUtils;

import org.dom4j.Document;

import org.dom4j.DocumentException;

import org.dom4j.DocumentHelper;

import org.dom4j.Element;

import org.dom4j.io.OutputFormat;

import org.dom4j.io.SAXReader;

import org.dom4j.io.XMLWriter;

import org.xml.sax.SAXException;

import com.alibaba.fastjson.JSON;

import com.alibaba.fastjson.JSONObject;

/**

 * JSON对象与XML相互转换工具类

 *

 * @author Logan

 * @createDate 2019-02-12

 * @version 1.0.0

 *

 */

public class JsonXmlUtils {

    private static final String ENCODING = "UTF-8";

    /**

     * JSON对象转漂亮的xml字符串

     *

     * @param json JSON对象

     * @return 漂亮的xml字符串

     * @throws IOException

     * @throws SAXException

     */

    public static String jsonToPrettyXml(JSONObject json) throws IOException, SAXException {

        Document document = jsonToDocument(json);

        /* 格式化xml */

        OutputFormat format = OutputFormat.createPrettyPrint();

        // 设置缩进为4个空格

        format.setIndent(" ");

        format.setIndentSize(4);

        StringWriter formatXml = new StringWriter();

        XMLWriter writer = new XMLWriter(formatXml, format);

        writer.write(document);

        return formatXml.toString();

    }

    /**

     * JSON对象转xml字符串

     *

     * @param json JSON对象

     * @return xml字符串

     * @throws SAXException

     */

    public static String JsonToXml(JSONObject json) throws SAXException {

        return jsonToDocument(json).asXML();

    }

    /**

     * JSON对象转Document对象

     *

     * @param json JSON对象

     * @return Document对象

     * @throws SAXException

     */

    public static Document jsonToDocument(JSONObject json) throws SAXException {

        Document document = DocumentHelper.createDocument();

        document.setXMLEncoding(ENCODING);

        // root对象只能有一个

        for (String rootKey : json.keySet()) {

            Element root = jsonToElement(json.getJSONObject(rootKey), rootKey);

            document.add(root);

            break;

        }

        return document;

    }

    /**

     * JSON对象转Element对象

     *

     * @param json JSON对象

     * @param nodeName 节点名称

     * @return Element对象

     */

    public static Element jsonToElement(JSONObject json, String nodeName) {

        Element node = DocumentHelper.createElement(nodeName);

        for (String key : json.keySet()) {

            Object child = json.get(key);

            if (child instanceof JSONObject) {

                node.add(jsonToElement(json.getJSONObject(key), key));

            }

            else {

                Element element = DocumentHelper.createElement(key);

                element.setText(json.getString(key));

                node.add(element);

            }

        }

        return node;

    }

    /**

     * XML字符串转JSON对象

     *

     * @param xml xml字符串

     * @return JSON对象

     * @throws DocumentException

     */

    public static JSONObject xmlToJson(String xml) throws DocumentException {

        JSONObject json = new JSONObject();

        SAXReader reader = new SAXReader();

        Document document = reader.read(new StringReader(xml));

        Element root = document.getRootElement();

        json.put(root.getName(), elementToJson(root));

        return json;

    }

    /**

     * Element对象转JSON对象

     *

     * @param element Element对象

     * @return JSON对象

     */

    public static JSONObject elementToJson(Element element) {

        JSONObject json = new JSONObject();

        for (Object child : element.elements()) {

            Element e = (Element) child;

            if (e.elements().isEmpty()) {

                json.put(e.getName(), e.getText());

            }

            else {

                json.put(e.getName(), elementToJson(e));

            }

        }

        return json;

    }

    /**

     * 文件内容转换成字符串

     *

     * @param filePath 文件路径

     * @return 内容字符串

     * @throws IOException

     */

    public static String fileToString(URL filePath) throws IOException {

        return IOUtils.toString(filePath, ENCODING);

    }

    /**

     * 文件内容转换成字符串

     *

     * @param filePath 文件路径

     * @return 内容字符串

     * @throws IOException

     */

    public static String fileToString(String filePath) throws IOException {

        return IOUtils.toString(Paths.get(filePath).toUri(), ENCODING);

    }

    /**

     * 字符串输出到文件

     *

     * @param str 字符串内容

     * @param filePath 文件路径

     * @throws IOException

     */

    public static void stringToFile(String str, String filePath) throws IOException {

        FileUtils.writeStringToFile(Paths.get(filePath).toFile(), str, ENCODING);

    }

    /**

     * 字符串输出到文件

     *

     * @param str 字符串内容

     * @param filePath 文件路径

     * @throws IOException

     */

    public static void stringToFile(String str, URL filePath) throws IOException {

        FileUtils.writeStringToFile(new File(filePath.getPath()), str, ENCODING);

    }

    /**

     * 字符串输出到文件

     *

     * @param str 字符串内容

     * @param file 输出文件

     * @throws IOException

     */

    public static void stringToFile(String str, File file) throws IOException {

        FileUtils.writeStringToFile(file, str, ENCODING);

    }

    public static void main(String[] args) {

        try {

            String filePath = "/User.xml";

            URL url = JsonXmlUtils.class.getResource(filePath);

            String content = JsonXmlUtils.fileToString(url);

            // System.out.println(content);

            JSONObject json = xmlToJson(content);

            System.out.println(JSON.toJSONString(json, true));

            String xml = JsonToXml(json);

            System.out.println(xml);

            System.out.println("----------------------------------------\n\n");

            xml = jsonToPrettyXml(json);

            System.out.println(xml);

            stringToFile(xml, "G:\\Temp\\Test\\User.xml");

        } catch (IOException e) {

            e.printStackTrace();

        } catch (DocumentException e) {

            e.printStackTrace();

        } catch (SAXException e) {

            e.printStackTrace();

        }

    }

}

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

<entity>

    <user>

        <id>1001</id>

        <username>Logan</username>

        <password>666666</password>

        <age>16</age>

    </user>

    <order>

        <id>2001</id>

        <price>9.99</price>

        <date>2019-02-12</date>

    </order>

</entity>