docs: private String getExceptionInfo(Throwable e, String systemDate, String newLineToken, String tabToken) {
  
          StringBuffer info = new StringBuffer();
          info.append(systemDate);
          info.append(tabToken);
          info.append("cause by: ");
          info.append(e.getClass().getName() + "--");
          info.append(e.getMessage());
          info.append(newLineToken);
          for (StackTraceElement stackTraceElement : e.getStackTrace()) {
              info.append(systemDate);
              info.append(tabToken);
              info.append(stackTraceElement);
              info.append(newLineToken);
          }
          if (null != e.getCause() && e.getCause() instanceof Exception) {
              info.append(getExceptionInfo((Exception) e.getCause(), systemDate, newLineToken, tabToken));
          }
          return info.toString();
      }