Java sending and receiving file (byte[]) over sockets

Solution 1:

The correct way to copy a stream in Java is as follows:

int count;
byte[] buffer = new byte[8192]; // or 4096, or more
while ((count = in.read(buffer)) > 0)
{
  out.write(buffer, 0, count);
}

Wish I had a dollar for every time I've posted that in a forum.

Solution 2:

Thanks for the help. I've managed to get it working now so thought I would post so that the others can use to help them.

Server:

public class Server {
    public static void main(String[] args) throws IOException {
        ServerSocket serverSocket = null;

        try {
            serverSocket = new ServerSocket(4444);
        } catch (IOException ex) {
            System.out.println("Can't setup server on this port number. ");
        }

        Socket socket = null;
        InputStream in = null;
        OutputStream out = null;
        
        try {
            socket = serverSocket.accept();
        } catch (IOException ex) {
            System.out.println("Can't accept client connection. ");
        }
        
        try {
            in = socket.getInputStream();
        } catch (IOException ex) {
            System.out.println("Can't get socket input stream. ");
        }

        try {
            out = new FileOutputStream("M:\\test2.xml");
        } catch (FileNotFoundException ex) {
            System.out.println("File not found. ");
        }

        byte[] bytes = new byte[16*1024];

        int count;
        while ((count = in.read(bytes)) > 0) {
            out.write(bytes, 0, count);
        }

        out.close();
        in.close();
        socket.close();
        serverSocket.close();
    }
}

and the Client:

public class Client {
    public static void main(String[] args) throws IOException {
        Socket socket = null;
        String host = "127.0.0.1";

        socket = new Socket(host, 4444);
        
        File file = new File("M:\\test.xml");
        // Get the size of the file
        long length = file.length();
        byte[] bytes = new byte[16 * 1024];
        InputStream in = new FileInputStream(file);
        OutputStream out = socket.getOutputStream();
        
        int count;
        while ((count = in.read(bytes)) > 0) {
            out.write(bytes, 0, count);
        }

        out.close();
        in.close();
        socket.close();
    }
}

Solution 3:

Here is the server Open a stream to the file and send it overnetwork

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;

public class SimpleFileServer {

  public final static int SOCKET_PORT = 5501;
  public final static String FILE_TO_SEND = "file.txt";

  public static void main (String [] args ) throws IOException {
    FileInputStream fis = null;
    BufferedInputStream bis = null;
    OutputStream os = null;
    ServerSocket servsock = null;
    Socket sock = null;
    try {
      servsock = new ServerSocket(SOCKET_PORT);
      while (true) {
        System.out.println("Waiting...");
        try {
          sock = servsock.accept();
          System.out.println("Accepted connection : " + sock);
          // send file
          File myFile = new File (FILE_TO_SEND);
          byte [] mybytearray  = new byte [(int)myFile.length()];
          fis = new FileInputStream(myFile);
          bis = new BufferedInputStream(fis);
          bis.read(mybytearray,0,mybytearray.length);
          os = sock.getOutputStream();
          System.out.println("Sending " + FILE_TO_SEND + "(" + mybytearray.length + " bytes)");
          os.write(mybytearray,0,mybytearray.length);
          os.flush();
          System.out.println("Done.");
        } catch (IOException ex) {
          System.out.println(ex.getMessage()+": An Inbound Connection Was Not Resolved");
        }
        }finally {
          if (bis != null) bis.close();
          if (os != null) os.close();
          if (sock!=null) sock.close();
        }
      }
    }
    finally {
      if (servsock != null)
        servsock.close();
    }
  }
}

Here is the client Recive the file being sent overnetwork

import java.io.BufferedOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.Socket;

public class SimpleFileClient {

  public final static int SOCKET_PORT = 5501;
  public final static String SERVER = "127.0.0.1";
  public final static String
       FILE_TO_RECEIVED = "file-rec.txt";

  public final static int FILE_SIZE = Integer.MAX_VALUE;

  public static void main (String [] args ) throws IOException {
    int bytesRead;
    int current = 0;
    FileOutputStream fos = null;
    BufferedOutputStream bos = null;
    Socket sock = null;
    try {
      sock = new Socket(SERVER, SOCKET_PORT);
      System.out.println("Connecting...");

      // receive file
      byte [] mybytearray  = new byte [FILE_SIZE];
      InputStream is = sock.getInputStream();
      fos = new FileOutputStream(FILE_TO_RECEIVED);
      bos = new BufferedOutputStream(fos);
      bytesRead = is.read(mybytearray,0,mybytearray.length);
      current = bytesRead;

      do {
         bytesRead =
            is.read(mybytearray, current, (mybytearray.length-current));
         if(bytesRead >= 0) current += bytesRead;
      } while(bytesRead > -1);

      bos.write(mybytearray, 0 , current);
      bos.flush();
      System.out.println("File " + FILE_TO_RECEIVED
          + " downloaded (" + current + " bytes read)");
    }
    finally {
      if (fos != null) fos.close();
      if (bos != null) bos.close();
      if (sock != null) sock.close();
    }
  }    
}