code: public static String toJson(HppRequest hppRequest) {
  		try {
  			return hppRequestWriter.writeValueAsString(hppRequest);
  		} catch (JsonProcessingException ex) {
  			LOGGER.error("Error writing HppRequest to JSON.", ex);
  			throw new RealexException("Error writing HppRequest to JSON.", ex);
  		}
  	}
docs: Method serialises <code>HppRequest</code> to JSON.
  
  @param hppRequest
  @return String