Re-using jgroups channel managed from domain.xml

[kristjan273]

Hi,

I would like to achieve some custom message sending/receiving through some (already created/open) jgroups channel.

I remember reading somewhere (can't recall where, maybe @Infinispan docs) that it is advisable to reuse the jgroups channel which is managed from doman.xml.

I would be glad if somebody would point me to some additional info page on the topic and/or if re-use is advisable, please provide some example how to access already managed channel programmatically. Is there a possibility of some Injection as resource?

thank you in advance,

K

[kristjan273]

By reading some more on topic I demistified this. It is shared transport introduced by jgroups and as can be seen from https://issues.jboss.org/browse/AS7-1768 the default singleton_name is 'udp'

[kristjan273]

I marked this discussion 'assumed answered', but digging further I would ask for some additional help. I see in https://issues.jboss.org/browse/AS7-541 that some channel factory exists. I have studied source from as clustering portion (specially how infinispan reuse the channel), but still don't see the way developer can use msc service inside the code.

Now question, is this service meant to be accessible from developer's point of view and how?

I think I would like to achieve that container creates and manages the jgroups channel for me and/or reuse the existing one (if possible). Can someone provide some example code for this case and/or hint if this is proper usage. Otherwise I will hold on the current implementation of my project where I create custom jgroups channel from code and maintain it.

tnx in advance

[kristjan273]

Ok, tried some more, googled for MSC injection (is there any doc/example on that?) ,checked the src from jboss-as-clustering-infinispan to see, how infinispan module does that (but is so far little to advanced code).

I have tried following

@PostConstruct
    private void start() {
        InjectedValue<ChannelFactory> channelFactory = new InjectedValue<ChannelFactory>();
        ChannelFactory value = channelFactory.getValue();
        try {
            createChannel = value.createChannel("udp");
            createChannel.connect("sysMsgs");
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

but getting the following error:

Caused by: java.lang.IllegalStateException: JBAS011048: Failed to construct component instance

(See attachment for more log)

I didn't know that service for  ChannelFactory and concept of reusing transport stack was already introduced in jboss5 (http://docs.jboss.org/jbossclustering/cluster_guide/5.1/html/clustering-blocks.chapt.html#clustering-blocks-jgroups-channelfactory). I would really go for the accessible service, just wonder how to get it from as7.

Anyone?

[alesj]

What exactly are you trying to do?

Adding external services can be done via POJO subsystem.

Otherwise you need to impl your own subsystem and "hardcode" the services.

(or you can modify some existing subsystem)

If you're around, we can discuss this here:

* http://pot.kiberpipa.org/super-fast-java-development-with-jbossas7-ales-justin-tomaz-cerar/

[kristjan273]

Tnx Aleš for invitation, been there, clarified on this.

Tomaž said what's the big idea to use jgroups channel directly if on top of it Infinispan is production ready.

I have rethinked quickly and actually can confirm that all (three) cases where our app used jchannel directly is able to be switched to infinispan clustered object.