Unable To Create Serversocket That Send Binary In Parts

I am trying to create a serversocket that send a binary in parts ie send 1024 bytes then wait for acknowledgement from the client before sending the next 1024. I am able to do it in udp but the client is tcp. This is my code so far

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
public class TestFtp {

[Code]....

I have not been able to send then receive acknowledgement before sending the next 1024 bytes.