Question

I have a listening port on my server that I’m connecting to using a Java class and the Socket interface, i.e.

Socket mySocket = new Socket(host,port); 

I then grab an OutputStream, decorate with a PrintWriter in autoflush mode and I’m laughing – except if the listening port closes. Then I get

tcp4       0      0  *.9999                 *.*                    LISTEN tcp        0      0  127.0.0.1.45737        127.0.0.1.9999         CLOSE_WAIT 

and I can’t seem to detect the problem in the program – I’ve tried using the isConnected() method on the socket but it doesn’t seem to know that the connection is closed.

I want to be aware of the problem the next time I try and write to the Socket so that I can try and reconnect and report the issue.

Any advice please?

Thanks all

Answer 1

Set a short timeout?

Does isOutputShutdown() not get you what you want?

You could always build a SocketWatcher class that spins up in its own Thread and repeatedly tries to write empty strings to the Socket until that raises a SocketClosedException.