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reading from TCP socket problem

Michal Bury

Joined: Sep 13, 2006
Posts: 6
Hi I am new with TCP socket's.
My problem is as follows:
I tried a sample program that listen as a server on desired port, read data from socket and send the data back (see code). But nothing happens. In network monitor I can see that the data from client are comming but nothing is sended back.
Can anybody help to understand where is my problem.


Joe Ess

Joined: Oct 29, 2001
Posts: 9189

The code looks fine to me. What do you mean by "nothing happens"?
How about putting in additional System.out.println() messages, for example immediately before and after echoServer.accept() and after the while(true) loop. That will help you establish if the code is doing what you think it is doing.
One thing I notice is that this code will only handle one client. Ever. So if you hooked up once and didn't restart the server, your next client will not be serviced (though I'd expect the while(true) to exit with an exception when the first client exited. . .)

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Michal Bury

Joined: Sep 13, 2006
Posts: 6
Ok. I found the problem. It was on the Client side. It sended data without
"end of line", therefore I can not use readln() but only read.
I agree. Here's the link:
subject: reading from TCP socket problem
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