code: public void send(String apiKey, String queue, final Object message) {
          checkNotNull(queue, "queue");
          try {
              URI uri = _queueService.clone()
                      .segment(queue, "send")
                      .build();
              _client.resource(uri)
                      .type(MediaType.APPLICATION_JSON_TYPE)
                      .header(ApiKeyRequest.AUTHENTICATION_HEADER, apiKey)
                      // Wrap the message in a JSONWrappedObject that forces Jersey to use Jackson to serialize it
                      // no matter what the type.  Otherwise null and String objects don't get serialized correctly.
                      .post(new JSONWrappedObject("", "", message));
          } catch (EmoClientException e) {
              throw convertException(e);
          }
      }
docs: Any server can handle sending messages, no need for @PartitionKey