Re: Help with OutputStream.send() method. I want to know how much data this method already sent.

From:

"Dalton Barreto" <daltonmatos@gmail.com>

Newsgroups:

comp.lang.java.programmer

Date:

6 Nov 2006 08:41:49 -0800

Message-ID:

<1162831309.591216.199610@k70g2000cwa.googlegroups.com>

Dalton Barreto wrote:

Hi,

I have a problem with my application that is:

Some times I have to send data to a server, and I do this using this
code:
  First I have to get the sockWriter:

try {
            sock = getSocket();
            sockReader = sock.getInputStream();
            sockWriter = sock.getOutputStream();
            String recv = receiveSigleLineResponse();
    }catch (IOException e){
            throw new ConnectionException(e.getMessage());
}

ok, at this point everything works. The problem begins every time I
need to send the data, and here is the code:

      sockWriter.write(new String(mailData + LINE_FEED + "." +
LINE_FEED).getBytes());

this lines works well, but once my program reaches this line of code,
it "hangs" until this function
returns, this is expected, of course. But I want the user to see a
progress bar showing how much data has already been sent to the server.
And I can't do this, because send() is blocking until all data have
been sent.
What I want is a way to keep checking how much data the function sent
so I can update the progress bar.

I don't know if I was clear, but thanks in advance.

Thanks!
  Dalton Barreto;

Two things.
One, don't send all of the bytes in one chunk. Split it into different
chunks.
Two, print out how many chunks have been sent so far.
Possibly having an 1024 byte chunk, you would be able to display(chunks
+ "k bytes have been sent")

So the class that sends the data has to know about the class that
implements the
progress bar, right?? This way the sender class will update the
progress directly, and
not the other way (the progress bar checking for total transfered
data), what is the
best way do implement this??

I tried to do something like this:
the class that sends the data increments a private variable, and the
class tha implements
the pBar keeps checking how much was sent so far. but this is bad,
because the only
way that I see to do this is: sleep some seconds e check again, then
get the totalBytes
transfered and do a += on the progerss status. But this is wrong,
because if the connection
is bad and the OS doesn't send any data in a short time slice the
progress bar would show
a inconsistent status (more data than actually transfered).

Is there any other way to do this 'comunication', between the sender
class and the pBar class, so the second show always a consistent status
value?

Thanks in advance!
Dalton Barreto;

PS: The class the send the data and the class that shows the progress
bar are two different
classes.