How to find the size of an object in Java Android

[109th_Regiment]

I'm a newbie in android and python, and I'm trying to establish a TCP socket connection between my android client and a python server. Every time I swipe in my app, I send the swipe movement's direction to the server.

//java client
           OutputStream output = client.getOutputStream();
           DataOutputStream out = new DataOutputStream(new BufferedOutputStream(output));

           byte[] msg;
           if(strings[1].equals("swipe"))
           {
               out.write(strings[1].getBytes());
               out.flush();
               //strings[0] contains the movement information in format of:
               //xmovement_ymovement
               //for example: 2.5365_8.5478
               msg = strings[0].getBytes();
               out.write(msg);
               out.flush();
           }

#python server
   #the 1024 is a temporary number I just put in there
   #because I don't know how to find the size of the data in the java client side
   request_byte = client_socket.recv(1024)
   print("reqeust_byte size: " + str(sys.getsizeof(request_byte)))
   request = request_byte.decode()
   print("Received " + request)

   if request == "swipe":
       movement_byte = client_socket.recv(1024)
       print("movement_byte size: " + str(sys.getsizeof(movement_byte)))
       movement_str = movement_byte.decode()
       x_movement, y_movement = movement_str.split("_")
       print("x: " + x_movement)
       print("y: " + y_movement)
       swipe(float(x_movement), float(y_movement))

When a simple button press is done and a single data is sent, the code works fine, but when I swipe and a lot of data is being sent in a short amount of time to the server, the data gets mixed up and turns unpredictable.

Now, as this post https://stackoverflow.com/questions/26641840/receiving-end-of-socket-splits-data-when-printed says, I know that I need to build a protocol that delineates messages, but on the Java client side, I can't get the size of the data I'm trying to send, so I'm stuck here.

This post https://stackoverflow.com/questions...-way-to-determine-the-size-of-an-object#52682 says I can find size of objects by using java.lang.instrument package, but I can't import java.lang.instrument.Instrumentation in android studio. Is there another way to find the size of an object in android studio?