Arun Arun - 3 months ago 29
Java Question

Server socket file transfer

I have used server socket concept in java to transfer files like images and videos. But when i receive at the client side, i am customizing the file names. Can i get the original name of the file as it is?

For Example:

If the file from server end for transfer is "abc.txt", i need this same name to be reflected in the client end(without passing the name separately).

In the server end:

public class FileServer {
public static void main (String [] args ) throws Exception {
// create socket
ServerSocket servsock = new ServerSocket(13267);
while (true) {
System.out.println("Waiting...");

Socket sock = servsock.accept();
System.out.println("Accepted connection : " + sock);
OutputStream os = sock.getOutputStream();
new FileServer().send(os);
sock.close();
}
}

public void send(OutputStream os) throws Exception{
// sendfile
File myFile = new File ("C:\\User\\Documents\\abc.png");
byte [] mybytearray = new byte [(int)myFile.length()+1];
FileInputStream fis = new FileInputStream(myFile);
BufferedInputStream bis = new BufferedInputStream(fis);
bis.read(mybytearray,0,mybytearray.length);
System.out.println("Sending...");
os.write(mybytearray,0,mybytearray.length);
os.flush();
}
}


In the client end:

public class FileClient{
public static void main (String [] args ) throws Exception {


long start = System.currentTimeMillis();


// localhost for testing
Socket sock = new Socket("127.0.0.1",13267);
System.out.println("Connecting...");
InputStream is = sock.getInputStream();
// receive file
new FileClient().receiveFile(is);
long end = System.currentTimeMillis();
System.out.println(end-start);

sock.close();
}

public void receiveFile(InputStream is) throws Exception{
int filesize=6022386;
int bytesRead;
int current = 0;
byte [] mybytearray = new byte [filesize];

FileOutputStream fos = new FileOutputStream("def");
BufferedOutputStream 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();
bos.close();
}
}

Answer

Yes, simply transfer the metadata (in your case myFile.getName()) before the actual file contents, and make client and server read and emit that metadata. It's a good idea to use established protocols, for example HTTP and its Content-Disposition header.