java.util.concurrentModification迭代JSONObject时的异常

        JSONObject dlCovs = jsonObject.getJSONObject("result").getJSONObject("cov_details");
        Iterator x = dlCovs.keys();
        while (x.hasNext()){
            String key1 = (String) x.next();
            String value1 = dlCovs.optString(key1);
            dlCovs.put("covabbrv",key1);
            dlCovs.put("dcIssuedt",value1);
            dlCovs.put("vecatg",key1);
            dlData.put("dlCovs", dlCovs);
        }

       /* dlCovs.put("covabbrv",cov);
        dlCovs.put("issue_date",issue_date);*/
        dlObj.put("status","valid");
        dlData.put("dlCovs", dlCovs);
        dlData.put("status","valid");

迭代while循环中的数据我得到java.util.concurrentModificationException,他们也是一个例子,当我试图调试它时,它将值存储在dlData.put(“dlCovs”,dlCovs)中,但是一旦它第二次迭代它就会抛出错误.
我遵循JSON值

 "cov_details": {
     "MCWG": "NA",
     "3WTR": "NA",
     "PSV BUS": "NA",
     "LMV": "NA",
     "INVCRG": "NA"
 },

任何帮助都将非常值得一提,非常感谢
    在此处输入代码

将项目放入单独的地图中,然后将其添加到“主”地图中：

  Map newEntries = new HashMap();
  Iterator x = dlCovs.keys();
  while (x.hasNext()){
    String key1 = (String) x.next();
    String value1 = dlCovs.optString(key1);
    newEntries.put("covabbrv",key1);
    // .. etc
  }

  dlCovs.putAll(newEntries);

另外：don’t use raw types.你应该声明x像：

Iterator<String> x = dlCovs.keys();

然后你不需要演员：

String key1 = x.next();

同理：

Map<String, String> newEntries = new HashMap<>();