Can I re-use a socket (2 way connection)

Question

I am sending various types of files across an socket. The files are going accross just fine. I do close the output stream on the client which wraps the socket. However, I would like to keep the socket open and send an XML file back to the client containing some information about what finally happens to the file. However, if I don't close the socket the file remains open and then will get munged. So, I guess I need a way to close the file writer but keep the socket open. Anyone know if this is possible or how to do this?
Here's my client/server.
<client>
...// basically gets the file name.
Socket sock = new Socket( host, port );
File fp = new File(fileName);
FileInputStream fins = new FileInputStream(fp);
long fsize = fp.length();
int bsize = 1024000;
byte[] bdata = new byte[bsize];
DataOutputStream o = new DataOutputStream(sock.getOutputStream());
int n=0;
while (fsize>0)
n = fins.read(bdata,0,bsize); // read 1mb from file
o.write(bdata,0,n); // write it to the socket
fsize-=n;
o.close();
System.out.println("File Sent");
</client>
<server>
public class XMLServer implements Runnable {
public static int DEFAULT_PORT = 22334;
private Socket request = null;
public XMLServer(Socket request) {
this.request = request;
public XMLServer(int port) {
try {
ServerSocket server = new ServerSocket( DEFAULT_PORT );
System.out.println( "Server starting" );
while ( true )
// Wait for client request
System.out.println( "Waiting...\n" );
Socket socket = server.accept();
System.out.println( "Request from client received. Processing request." );
// Handle request
XMLServer handler = new XMLServer( socket );
Thread thread = new Thread( handler );
thread.start();
} catch(IOException ioex) {
ioex.printStackTrace();
public void run() {
try {
handleRequest();
} catch(IOException ioex) {
System.out.println("Error occurred while trying to service request.");
System.out.println("Server stopped.");
ioex.printStackTrace();
System.exit(0);
public void handleRequest() throws IOException {
File fp = new File(fileName);
FileOutputStream fout = new FileOutputStream(fp);
int bsize = 1024000;
byte[] bdata = new byte[bsize];
DataInputStream i = new DataInputStream(request.getInputStream());
int n=0;
long totalbytes = 0;
System.out.println("Receiving file");
while ((n = i.read(bdata,0,bsize)) > 0)
fout.write(bdata,0,n); // write it to the socket's stream
totalbytes += n;
System.out.println("File Read Complete " + totalbytes + " in length.");
fout.close();
System.out.println("File Closed");
<server>

Answer 1

You understand your problem completely.
While convienient, it is not practical to use the
socket streams that way in your application, because
Sun early on made the decision that closing a stream
wrapper always closes the inner stream. (Personally I
wish they hadn't) Anyway, you'll now have to read the
file into a byte array first, and send that array over
the output stream.
Makes sense?Ahhh.. Ok, so you're saying in order to keep the stream open, I would have to send the file in a packet structure so I can send the server the length of the file (in bytes) and then the file so that the server would know to read N bytes and I could then avoid immediately closing the socket? I guess that sounds ok. Kind o f wierd though.. Maybe I'll just use the ProgressMonitor and let that suffice.
Eeek, tell me it isn't so...