Java Socket How do I tell when the connection is closed and how do I open it again

[jlparise]

Hey everyone,

I am really rusty on my Java socket programming and am having some confusing problems. I don't need the code debugged(even though it doesn't work). I'm not going to make you dig through all the abstraction layers and such.

Anyways here is my issue. The application sends a request for data to the server and the server responds. However, the server then sends a TCP Fin message to close the connection which I can see through wire shark.

How do I tell when the connection is closed and how do I open it again? Also, what do isClosed, isBound and isCOnnected do in the Java socket class.

My program is crashing because I am trying to write to a closed socket(I think).


However, I get the following weird scenario:

isConnected True
isBound True
isClosed False

This would seem to indicate the socket is still open, but when I write to the socket I get the following Exception:

java.net.Socket Exception: Software caused connection abort: socket write error
at java.net.Socket OutputStream.so cketWrite0(Nati ve Method)

Can anyone explain what is going on?

Thanks,

Jon

[RedSon]

Please remember to provide a meaningful Title for any threads started (see the FAQ entry Use a Good Thread Title).

This helps to ensure that other members, and also the general public, will have a better chance of finding answers to any similar questions.

MODERATOR

[r035198x]

Hey everyone,

I am really rusty on my Java socket programming and am having some confusing problems. I don't need the code debugged(even though it doesn't work). I'm not going to make you dig through all the abstraction layers and such.

Anyways here is my issue. The application sends a request for data to the server and the server responds. However, the server then sends a TCP Fin message to close the connection which I can see through wire shark.

How do I tell when the connection is closed and how do I open it again? Also, what do isClosed, isBound and isCOnnected do in the Java socket class.

My program is crashing because I am trying to write to a closed socket(I think).


However, I get the following weird scenario:

isConnected True
isBound True
isClosed False

This would seem to indicate the socket is still open, but when I write to the socket I get the following Exception:

java.net.Socket Exception: Software caused connection abort: socket write error
at java.net.Socket OutputStream.so cketWrite0(Nati ve Method)

Can anyone explain what is going on?

Thanks,

Jon

You can read the specs for the Socket class to find out more about those methods.