CODEWITHSUNDEEP
javarmi
Rob P.
Rob P.

Reputation: 15091

Detecting Server Crash With RMI

I'm new to Java and RMI, but I'm trying to write my app in such a way that there are many clients connecting to a single server. So far, so good....

But when I close the server (simulating a crash or communication issue) my clients remain unaware until I make my next call to the server. It is a requirement that my clients continue to work without the server in an 'offline mode' and the sooner I know that I'm offline the better the user-experience will be.

Is there an active connection that remains open that the client can detect a problem with or something similar - or will I simply have to wait until the next call fails? I figured I could have a 'health-check' ping the server but it seemed like it might not be the best approach.

Thanks for any help

Upvotes: 2

Views: 797

Answers (3)

Thorbjørn Ravn Andersen
Thorbjørn Ravn Andersen

Reputation: 75426

(Untested). Having a separate RMI call repeatedly into the server, which just does a "wait X seconds" and then return, should be told that the execution has failed when the server is brought down.

Upvotes: 1

asdfjklqwer
asdfjklqwer

Reputation: 3594

I looked into this a bit when I was writing an RMI app (uni assignment) but I didn't come across any inbuilt functionality for testing whether a remote system is alive. I would just use a UDP heartbeat mechanism for this.

Upvotes: 1

Andre
Andre

Reputation: 9170

actually i'm just trying to learn more about RMI and CORBA but i'm not that far as you are. all i know is that those systems are also built to be less expensive, and as far as i know an active conneciton is an expensive thing.

i would suggest you use a multicast address to which your server sends somehow "i'm still here" but without using TCP connections, UDP should be enough for that purpose and more efficient.

Upvotes: 1

Related Questions