code: public void setRespondToPayloadType(String respondToPayloadType) throws UnsupportedPayloadType {
      // Sanity check on the payload type values. Should be XML or JSON
      // If the probe goes out with a bad value here, then the Responder may have
      // problems
      if (respondToPayloadType == null || respondToPayloadType.isEmpty() || (!respondToPayloadType.equals(ProbeWrapper.JSON) && !respondToPayloadType.equals(ProbeWrapper.XML)))
        throw new UnsupportedPayloadType("Attempting to set payload type to: " + respondToPayloadType + ". Cannot be null or empty and must be " + ProbeWrapper.JSON + " or " + ProbeWrapper.XML);
  
      _probe.setRespondToPayloadType(respondToPayloadType);
    }
docs: set the payload type for the response from the Responder. It only support
  XML and JSON.
  
  @param respondToPayloadType a payload type string - XML or JSON
  @throws UnsupportedPayloadType if you don't pass in XML or JSON