Experimental Physics and
Industrial Control System

Matej Sekoranja <[email protected]> · Thu, 29 Nov 2012 21:52:28 +0100

Hi,

On Thu, Nov 29, 2012 at 9:07 PM, J. Lewis Muir <[email protected]> wrote:
> On 11/29/12 12:30 PM, Shankar, Murali wrote:
>>
>> Just wanting to check if anyone uses CAJ (pure Java CA client) clients in production especially in combination with IOC's that are using the native CA library.
>> I've pinged a few folks offline; however, it was thought that a community wide repoll would probably be beneficial.
>
> Hi, Murali.
>
> We use it in production with IOCs using the native CA library at
> IMCA-CAT (Sector 17 at the APS).
>
> I suspect NSLS-II uses it since they indicated a commitment to ensure it
> is maintained back in March of 2009:
>
>   http://www.aps.anl.gov/epics/tech-talk/2009/msg00544.php
>
>> Known issues that I am already aware of (thanks Michael and Eric)
>> 1) Interoperability issue with the CA Gateway and clients using monitors with DBE_PROPERTY.
>
> It took almost three years, and I haven't tried using it, but the CAJ
> Changes page shows version 1.1.10, released on 2012-06-14, with a
> description of "DBE_PROPERTY support".  Is your problem that it seems
> CAJ doesn't support the DBE_PROPERTY event type, or is it a problem
> specific to using DBE_PROPERTY with the CA Gateway?

Yes, JCA and CAJ where added DBE_PROPERTY support.

>
> Do you know where the problem lies?  Have you filed a bug report with
> either project?
>
> Checking the CAJ web site, it seems there is no bug tracker set up for
> CAJ; you have to send an email.  I think CAJ is big enough and used by
> enough people that a bug tracker is warranted.  Matej, would you be up
> for enabling a bug tracker for CAJ?

Since JCA/CAJ are hosted as SourceForge project it's easy to enable
bug tracker feature.
Here it is: https://sourceforge.net/tracker/?group_id=336891

>> 2) For CA Access Security, CAJ uses full hostnames (with domain) and libca uses short host names (without domain)
>
> This sounds like a bug to me.  I would expect the two to behave
> identically.  I don't know what the correct behavior is.  Maybe libca is
> not behaving in accordance with the spec, or maybe the short hostname is
> according to spec.  If the latter, and if Matej (the developer of CAJ)
> does not want to change this behavior as the default, perhaps support
> could be added for a compatibility-mode option/property to enable the
> use of the short hostname in CAJ?

The method CAJ uses to get hostname is (or was in 2006) not
deterministic - it can return long or short name. There is an JVM
"-DCAJ_STRIP_HOSTNAME" option to strip SHN from possibly returned FQDN
(e.g. alma.hq.eso.org -> alma).

>> To clarify, a monitor won't clear in CAJ without an explicit IO flush. In JCA/JNI, the monitor will clear without the IO flush, so the behavior is different.

> Hi, Tom.

> I didn't know about this; thanks for reporting it.  Does Matej know about it?

No. Thanks.
(It's super easy to "fix")

Matej

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System