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From: Robert Klemme <shortcutter@googlemail.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: "heartbeat" approach
Date: Sat, 02 Feb 2013 00:13:04 +0100
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On 01.02.2013 23:46, Arne Vajh=F8j wrote:
> On 2/1/2013 11:11 AM, bob smith wrote:
>> What is the best way to handle a situation where you want a socket to
>> send a "heartbeat" every ten minutes?  I was thinking it would be
>> simple to have a single thread do all the "heartbeat" sending.

http://docs.oracle.com/javase/6/docs/api/java/util/Timer.html

>> However, that means there could be multiple threads writing to one
>> socket.  Do I need to do anything special to have multiple threads
>> writing to one socket?  Is there a better way?
>
> You can certainly let the two writing thread synchronize on
> Socket or OutputStream objects to make it thread safe.

Yes, _some_ form of synchronization is needed.

> You could also funnel all writes through the same
> thread (a writer thread) via some in memory data structure
> (which you would then need to synchronize on).

The details of course depend on the nature of the heartbeat (e.g. can it =

be omitted if there was regular traffic in the meantime?  How much delay =

for the heartbeat is allowed etc.).

> The last option would end up as much more complex
> code from start, but I believe that the design may
> end up being preferable as the solution itself evolves.
> Consider how many places you nee to change if you want to
> switch from TCP to UDP.

We could certainly come up with better solutions if we had more=20
information about the scenario.

Kind regards

	robert

--=20
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/