<dependency>
     <groupId>maven</groupId>
     <artifactId>dom4j</artifactId>
      <version>1.7-20060614</version>
</dependency>

import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import java.util.List;

/**
 * @project 
 * @Description XML轉json對象工具類
 * @Author songwp
 * @Date 2022/9/20 9:54
 * @Version 1.0.0
 **/
public class XmltoJsonUtil {

    /**
     * 將xml轉換為json對象
     */
    public static JSONObject xmlToJson(String xml) throws DocumentException {
        JSONObject jsonObject = new JSONObject();
        Document document = DocumentHelper.parseText(xml);
        //獲取根節點元素對象
        Element root = document.getRootElement();
        iterateNodes(root, jsonObject);
        return jsonObject;
    }

    /**
     * 遍歷元素
     * @param node
     * @param json
     */
    private static void iterateNodes(Element node, JSONObject json) {
        //獲取當前元素名稱
        String nodeName = node.getName();
        //判斷已遍歷的JSON中是否已經有了該元素的名稱
        if(json.containsKey(nodeName)){
            //該元素在同級下有多個
            Object Object = json.get(nodeName);
            JSONArray array = null;
            if(Object instanceof JSONArray){
                array = (JSONArray) Object;
            }else {
                array = new JSONArray();
                array.add(Object);
            }
            //獲取該元素下所有子元素
            List<Element> listElement = node.elements();
            if(listElement.isEmpty()){
                //該元素無子元素，獲取元素的值
                String nodeValue = node.getTextTrim();
                array.add(nodeValue);
                json.put(nodeName, array);
                return ;
            }
            //有子元素
            JSONObject newJson = new JSONObject();
            //遍歷所有子元素
            for(Element e:listElement){
                //遞歸
                iterateNodes(e,newJson);
            }
            array.add(newJson);
            json.put(nodeName, array);
            return ;
        }
        //該元素同級下第一次遍歷
        //獲取該元素下所有子元素
        List<Element> listElement = node.elements();
        if(listElement.isEmpty()){
            //該元素無子元素，獲取元素的值
            String nodeValue = node.getTextTrim();
            json.put(nodeName, nodeValue);
            return ;
        }
        //有子節點，新建一個JSONObject來存儲該節點下子節點的值
        JSONObject object = new JSONObject();
        for(Element e:listElement){
            //遞歸
            iterateNodes(e,object);
        }
        json.put(nodeName, object);
        return ;
    }

    public static void main(String[] args) {
        try {
            JSONObject object = XmltoJsonUtil.xmlToJson("<auibinsurancecallback><policyinfo><transtype>TKTS</transtype><eticketno>xxx</eticketno><flightnumber>xxx</flightnumber><flightdate>2019-10-16</flightdate><operatetime>2019-10-16 17:20:00</operatetime><insureno>1910161720056066735</insureno><agreeno>102160199</agreeno><policyno></policyno><policyurl><!--[CDATA[]]--></policyurl></policyinfo><returninfo><serialnumber>2019103015284949545354</serialnumber><retruncode>0</retruncode><errormessage><!--[CDATA[xxx]]--></errormessage></returninfo></auibinsurancecallback>");
            System.out.println(object);
        } catch (DocumentException e) {
            e.printStackTrace();
        }
    }
}

{
    "auibinsurancecallback":{
        "returninfo":{
            "errormessage":"",
            "retruncode":"0",
            "serialnumber":"2019103015284949545354"
        },
        "policyinfo":{
            "policyurl":"",
            "operatetime":"2019-10-16 17:20:00",
            "transtype":"TKTS",
            "flightdate":"2019-10-16",
            "insureno":"1910161720056066735",
            "flightnumber":"xxx",
            "agreeno":"102160199",
            "policyno":"",
            "eticketno":"xxx"
        }
    }
}