code: private static Deserializer<?> getDeserializer(Properties props, Optional<Deserializers> deserializerType) throws ReflectiveOperationException {
  
      Deserializer<?> deserializer;
      if (deserializerType.isPresent()) {
        deserializer = ConstructorUtils.invokeConstructor(deserializerType.get().getDeserializerClass());
      } else {
        deserializer = Deserializer.class
            .cast(ConstructorUtils.invokeConstructor(Class.forName(props.getProperty(KAFKA_DESERIALIZER_TYPE))));
      }
      deserializer.configure(PropertiesUtils.propsToStringKeyMap(props), false);
      return deserializer;
    }
docs: Constructs a {@link Deserializer}, using the value of {@link #KAFKA_DESERIALIZER_TYPE}.