如何在iOS(Swift或ObjectiveC)中实现这样的套接字调用?

这是Java中进行套接字调用的代码,但我想知道如何在iOS中复制此代码或类似的代码(Swift或Objective-C)

public String MakeSocketRequest() {
    DataInputStream inputSt;
    DataOutputStream outputSt;
    Socket socket = new Socket(InetAddress.getByName("socketurl.io"), 40008);
    String jsonStr = "{\"id\":1,\"method\":\"themethod\"}";
    inputSt = new DataInputStream(socket.getInputStream());
    outputSt = new DataOutputStream(socket.getOutputStream());
    PrintWriter pw = new PrintWriter(outputSt);
    pw.println(string);
    Log.d("PrintWriter", jsonStr);
    pw.flush();
    BufferedReader bfr = new BufferedReader(new InputStreamReader(inputSt));
    JSONObject json = new JSONObject(bfr.readLine());
    Log.d("Json", json.toString());
    inputSt.close();
    outputSt.close();
    return json.toString();}