Experimental Physics and
Industrial Control System

Hi Simon, 

   Your work looks interesting.   A few questions:

>> 1. Java Channel-Access Client Library "ca"

Should we combine / merge / abandon the JCA / CAJ library?   Looks like no one is really maintaining the old library and in fact it appears some of the original CAJ developers are working on the newer "ca" library.   

Much of the code appears to be copied from JCA / CAJ anyways, with a modern API on top.   Though, it does seem the internal threading model has been a moving target through the years.  A few years ago I thought about using "ca", but noticed it was using an experimental LMax Distruptor with questionable benefit.   I see that has been removed: https://github.com/channelaccess/ca/issues/93, but I do see some other internal concurrency and threading model changes that could use some explanation.  

>> 2. Wica-HTTP  (Wica = "Web Interface for Control Applications")

There are a lot of these now.  I'll update my list here:

https://github.com/JeffersonLab/epics2web/wiki/Similar-Projects

A comparison might be useful.   One thing that jumps out is that you use Server Side Events (SSE).  These weren't really an option a few years ago due to Internet Explorer not supporting them.   Now that Microsoft Edge uses Chromium under the hood that's no longer an issue.

>> 3. Wica-JS 

Looks like you've got to be web developer to use this library?     Maybe a builder interface like EDM/CSS is in the works?  For example: https://github.com/JeffersonLab/puddysticks