code: @Override
  	public Object convertJsonToJava(String jsonArg, Type paramType, Annotation[] parameterAnnotations) throws JsonUnmarshallingException, JsonMarshallerException {
  		if ("null".equals(jsonArg)) {
  			return null;
  		}
  		JsonUnmarshaller juma = getJsonUnmarshallerAnnotation(parameterAnnotations);
  		if (null != juma) {
  			Object result = getResult(jsonArg, argumentServices.getIJsonMarshallerInstance(juma.value()), juma.type());
  			argumentServices.checkType(result, paramType);
  			return result;
  		} else {
  			return convertArgument(jsonArg, paramType);
  		}
  	}
docs: Convert json to Java
  
  @param jsonArg
  @param paramType
  @param parameterAnnotations
  @return
  @throws org.ocelotds.marshalling.exceptions.JsonUnmarshallingException
  @throws org.ocelotds.marshalling.exceptions.JsonMarshallerException