public static boolean checkWhetherUsePosition(String ids) {
        boolean flag = true;
        for( String id : StringUtils.split(ids, ",")) {
            if (!NumberUtils.isNumber(id)) {
                flag= false;
                break;
            }
        }
        return flag;
    }
check whether use position to generation doc's id
eg : |1,2,3 -> true
     |id,name,addr -> false
@param ids
@return
elasticsearch6/elasticsearch6-sink/src/main/java/com/dtstack/flink/sql/sink/elasticsearch/Es6Util.java