ReadUTF causing socket failure

Question

Hi
I am having a problem where occasionally readUTF is not getting the data sent from the client side of the socket, plus the socket is then not able to read any more data (no exceptions thrown).
I have caught some data from a situation where it has happened. It doesn't look like there's anything wrong with the data. Could anyone advise me on this? Is there a different way I should be approaching this?
Client side code:
try {
    System.out.println("DEBUG: writeInt: " + cmd);
    System.out.println("DEBUG: writeUTF: " + cmdString);
    o.writeInt(cmd);
    o.writeUTF(cmdString);
    o.flush();
    System.out.println("DEBUG: sent");
catch(IOException ex) {
    // processing IOException
catch(Exception ex) {
    // processing Exception
}Server side code:
try {
    while(running) {
        this.yield();
        int cmd = i.readInt();
        System.out.println("DEBUG: cmd: " + cmd);
        String cmdString = i.readUTF();
        System.out.println("DEBUG: cmdString: " + cmdString);
        this.commandReceived(cmd, cmdString);
catch (IOException ex) {
    //processing IOException
catch (Exception ex) {
    //processing Exception
finally {
    //processing finally
}snapshot from log at the point it fails:
client side log:
DEBUG: writeInt: 16
DEBUG: writeUTF: ||508^^filter.symbol.txt||720^^false||700^^3||703^^0||719^^false||705^^0||706^^0||702^^0||704^^0||701^^1||507^^VOD||
DEBUG: sent
DEBUG: writeInt: 16
DEBUG: writeUTF: ||720^^false||700^^2||703^^147||719^^false||705^^420||706^^300||702^^0||704^^69||701^^8||
DEBUG: sent
server side log:
cmd: 16
DEBUG: cmdString: ||508^^filter.symbol.txt||720^^false||700^^3||703^^0||719^^false||705^^0||706^^0||702^^0||704^^0||701^^1||507^^||
DEBUG: cmd: 16
DEBUG: cmdString:
The point being that there is not much difference between the first set of data that is sent and the second. But the second String value never gets from writeUTF to readUTF. And no exceptions are thrown.
Any advice on this would be much appreciated.
Thanks
Glyn

Answer 1

If you wanted to, you could use writeLong() on the datainputstream to send the number of bytes you are using in your byte array in writeBytes(). Then on the dataoutputstream you could use readFully() with a byte array of the size specified by readLong().
Just a thought.
K