Show IP address of host in ConnectException

Andrey Turbanov turbanoff at gmail.com
Fri Jul 21 09:32:54 UTC 2023


Hello.

Recently I was struggling with troubleshooting the Socket connection
to a server via DNS address.
There were multiple IPs assigned to the same DNS address and I wanted
to know exactly which IP java is trying to connect.
Unfortunately default ConnectException doesn't show anything useful in
the exception message

java.net.ConnectException: Connection refused

Even if I enable enhanced exception info
'-Djdk.includeInExceptions=hostInfo' I still only get the DNS address
in the exception message.

java.net.ConnectException: Connection timed out: connect:
myprod-app.global.mycompany.ro:5001

Is it possible to enhance the exception message to show used IP too?
Perhaps guarged with another JVM option.
I think it would be very useful for troubleshooting.

Andrey Turbanov


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