code: protected void addParameters(StringBuilder result) {
          result.append("ts=");
          result.append(timestamp);
          result.append(",headers=");
          result.append(headers);
          result.append(",body=");
          result.append(body);
          result.append(",messageId=");
          result.append(messageId);
          result.append(",timeToLive=");
          result.append(timeToLive);
          result.append(",clientId=");
          result.append(clientId);
          result.append(",destination=");
          result.append(destination);
      }
docs: Add message properties to string.
  
  @param result
  <code>StringBuilder</code> to add properties to