Transfering files through sockets

Hi
I am still having difficulties making this work.
I want to transfer a file (.exe, .zip) etc through a socket.
I have created a fileinputstream to the file, and read in all its bytes.
I then create an outputstream with the sockets output stream(socket is called incomming):
FileInputStream fin = new FileInputStream("D:\\steve.txt");
int size = fin.available();//for they byte array!
System.out.println("Number of bytes in this file is " + size);
byte b[] = new byte[size];//byte buffer holds the exact number of bytes the file contains!
fin.read(b);
OutputStream fileSender = incomming.getOutputStream();
fileSender.write(b, 0, size);
fileSender.close();
I am positive the byte array holds all the bytes in the file as i have tested that.
The problem is i dont seem to get anything out the client end. I pass along the file size and construct a byte array to hold it this is the client code:
InputStream inFile = soc.getInputStream();
populateTextArea("reading bytes!");
byte b[] = new byte[inLineNum]; //inLIneNum is the correct size for sure
inFile.read(b,0, inLineNum);
FileOutputStream foutnew = new FileOutputStream("C:\\TEMP01\\STevenTESTtest.txt");
foutnew.write(b);
The resulting file contains nothing, all it contains is a load of ascii code (00).
Any suggestions please, I'm probably missing something really dumb but I've spent about 5 hours and am totally fed up with it.
Steve

hehe it was working all the time, its just that my test files are large (typically over 5 meg) so its taking ages to transfer....So, does anyone know how to speed up a socket connection (if its even possible).
Cheers
Steve

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Transfering a file through Socket programming

Hi all,
I want to return a file from server to client through a socket. I tried using ObjectOutput Stream where in I returned a java.io.File from server. But at client side when I say file.getLeangth() it comes as 0 and if I try to assign FileInputStream on the object it throws an exception as the file not found as the path associated with the file will be of Server.
So can anyone help as to how to transfer a file through socket programming???
thx in advance
MK

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Hi
I am writing a client server app, and am communicating between the clients and server using the Socket and Serversocket class's. Transfering strings is very easy, but i also want to transfer files. I usually use Fileinputstream/fileoutputstream in normal circumstances, but i dont think this will work with sockets.
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Just create the InputStream to your file, read in some bytes, write the bytes to the sockets OutputStream, voila!
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[http://forums.sun.com/thread.jspa?forumID=11&threadID=390636] this may help you

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Can anyone tell me that how can i send files from server to the client through socket programming.
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Thanks for ur help.
but i have got it. i have designed a client and server. Client requests the server to send a specif file (Client takes the path of file from user). And server sends the file to the client.
I have checked this program on many files. like *.exe, *.txt, *.dat, *.zip, *.mp3, *.jpg.
it worked smoothly. I have test to trasfer a file of 700MB and it worked correctly.
Ooops! i did not check it on Network. i run these program on my own computer. both client and server were running on same computer.
but i am facing a little problem. that is: the speed of trasfering the files is very slow.
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And plz tell me how can i trasfer a complete directory just as i trasfered file over the sockets. (Remember: a dircetory may or may not contains may other files and also other directories
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here is the code:
*          CLIENT            *
import java.net.*;
import java.io.*;
public class TransferClient
    public static void main(String[] args)
        try
             int fileSize = 0;
             int readBytes = 0;
             final int BUFFER_SIZE = 512;
             byte[] buffer = new byte[BUFFER_SIZE];
               Socket sockClient = new Socket(InetAddress.getLocalHost(),2000);
               DataInputStream dataInputStream = new DataInputStream(sockClient.getInputStream());
               BufferedOutputStream bufferedOutputStream = new BufferedOutputStream(new FileOutputStream("filename.ext"));
               BufferedReader inputUser   = new BufferedReader(new InputStreamReader(System.in)); //For User input
               PrintWriter output = new PrintWriter (sockClient.getOutputStream(), true);     //To send the user input to the server
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}//end class TransferClient
*          SERVER            *
import java.io.*;
import java.net.*;
public class TransferServer
    public static void main(String[] args)
         int fileSize = 0;
         int readBytes = 0;
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         byte[] buffer = new byte[BUFFER_SIZE];
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Transfering Files using Sockets

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========
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=======
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Ah, thanks a lot for the replies.
It appears that i had some kind of writing to file error in server code at: fos.write(input);
Its been fixed now.
Non the less thank you very much for bothering :-)
A silly question though. How is it possible to retain filename and filetype when sending a file? i.e. instead of having a FileOutputStream writing to a predefined by a string File (i.e. File file = new File("a_picture.jpg");) being able to send any type of file and keep their current format and name?
I assume you should first send a string with the file name but the BufferedInputStream i have at the server mixes up both String and actual file bytes.
Excuse me for the long question
Kind Regards
Chris

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Hello,
My application has a server and it has to read a file that is sent by the client.. how can the server read a file sent by the client through sockets?????
Edited by: s_coder on Feb 19, 2009 11:20 PM

s_coder wrote:
Yes i read it but there input is given from the client to the server through the standard input stream.... how can i transfer a file thru the standard input stream? and the accept it at the server side???Come on mate. You need to be able to add two and two on your own.
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Either you didn't really read the tutorial or you're pretty darn hopeless. Why don't you try and really follow the tutorial, not just glance at each page but understand what it is saying. Then make an attempt to write your program and if you get stuck come back with your code. Be sure to use the code formatting tags when you show us your code.

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Transfering files through sockets

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