How to send Json object through java sockets?
Instead of using ObjectOutputStream, you should create an OutputStreamWriter, then use that to write the JSON text to the stream. You need to choose an encoding - I would suggest UTF-8. So for example:
JSONObject json = new JSONObject();json.put("type", "CONNECT");Socket s = new Socket("192.168.0.100", 7777);try (OutputStreamWriter out = new OutputStreamWriter( s.getOutputStream(), StandardCharsets.UTF_8)) { out.write(json.toString());}