廢話不多說，直接上程式碼

/**
 * 處理json資料
 * @param jsonString
 */
public static String jsonToXmlUtil(String jsonString){
    if(!StringUtils.hasText(jsonString)){
        log.error("{}","請求引數不能為空");
        throw new BizException("EEEEEE","請求引數不能為空");
    }
    JSONObject jsonObj=null;
    try{
        //格式化JSON資料，將json字串轉化為JSONObject並將資料的key以字母順序排序
 

        jsonObj=JSON.parseObject(jsonString);
        }catch(Exception e){
        log.error("{}","請求引數格式有誤");
        throw new BizException("EEEEEE","請求引數格式有誤");
    }
    String xmlResult=null;
    Document document=DocumentHelper.createDocument();
    document.setXMLEncoding("UTF-8");
    Element rootEle=document.addElement("Message"
 
);
    Element element=rootEle.addElement("Public");
    jsonObjToXml(jsonObj,element);
    xmlResult=document.asXML();
    return xmlResult;
}

public static void jsonObjToXml(JSONObject jsonObject,Element element){
    for(String key:jsonObject.keySet()){
        if(jsonObject.get(key)instanceof JSON){
            Element child=element.addElement(key);
            jsonObjToXml((JSONObject)jsonObject.get(key),child);
        }else
 
{
            Element child=element.addElement(key);
            child.addAttribute("value",jsonObject.get(key).toString());
        }
    }
}

測試：

public static void main(String[] args) throws Exception {
    String json = "{\"TxnBatchNo\":\"20170607152322\",\"TxnSeq\":\"1\",\"CardNo\":\"2017000100000003\",\"AAA\":{\"hello\":\"nihao\",\"hey\" : \"hai\",\"world\": \"hee\"},\"BBB\":{\"hello\":\"nihao\",\"hey\" : \"hai\",\"people\": {\"d\" : \"dog\",\"c\" : \"\",\"e\" : {\"hello\":\"nihao\",\"hey\" : \"hai\",\"tiger\": {\"d\" : \"dog\",\"c\" : \"\",\"e\" : \"elepahant\"}}}}}";
    System.out.println(jsonToXmlUtil(json));
}

輸出結果：

<?xml version="1.0" encoding="UTF-8"?>
<Message><Public><BBB><hello value="nihao"/><hey value="hai"/><people><d value="dog"/><e><hello value="nihao"/><hey value="hai"/><tiger><d value="dog"/><e value="elepahant"/><c value=""/></tiger></e><c value=""/></people></BBB><AAA><hello value="nihao"/><hey value="hai"/><world value="hee"/></AAA><TxnSeq value="1"/><TxnBatchNo value="20170607152322"/><CardNo value="2017000100000003"/></Public></Message>