Experimental Physics and
Industrial Control System

Marty Kraimer <[email protected]> · Mon, 16 Mar 2015 13:52:13 -0400

On 03/16/2015 10:49 AM, Ricardo Herrero wrote:

Hello,

 I´m still trying to get a Monitor to work in JAVA, and even I´m

learning a lot, there are many things I don´t understand yet. If

someone could help me with these questions I would really appreciate it.

1. There´s an package in pvData called Monitor, in which you have

MonitorAlgorithm class, Do I have to create the algorithm of the

Monitor? MonitorQueue, do I need to create a Queue to store the

Monitor Elements?

2. Object Monitor does exist both in server and client, or (in the

server side) do I just have to create a PVAccessServer and it creates

automatically a Monitor?

3. What is the function of the Requester, I can´t see the way they

work, its functions.

4. I have also found org.epics.pvaccess.server.impl.remote.handlers,

they seem to have implemented most of the interfaces, like

MonitorHandler, how can I use them? Do I avoid using directly Monitor,

Channel and PVAccessServer, on behalf of the MonitorHandler?

5. When I try to create a Server throught ServerFactory I have seen

that the Threads are created with the name PVAccessServer, hardcoded,

and I don´t know how can I change it.

Any help will be welcomed, thanks in advance.
Yours, Ricardo Herrero

Quick answer.

There is a new mercurial repository pvDatabaseJava.
Please try it.

Longer answer.

There is a mercurial repository that is not a component of the V4

releases named pvIOCJava.

It has lots of code including a complete implementation of a local

pvAccess server.

It also has lots that seemed, at the time, to be good ideas but no one

has bought in.

For C++, pvDatabaseCPP is a component of the latest V4 release.

It provides a complete implementation of a local pvAccess server except

channelRPC which is provided by pvAccess itself.

It  does not implement any of the other features that pvIOCJava provides.

I hope that pvDatabaseJava will be a component of the next V4 release.

It also has a complete implementation of a local pvAccess server except

channelRPC.

And again does not implement any of the other features of pvIOCJava.

What you have to do to implement a service is to provide a PVStructure

with the data your service requires and a process method.

pvDatabase does the rest, i.e. implements ChannelProvider, Channel,

ChannelGet, ChannelPut, ChannelPutGet, Monitor, and ChannelArray.

With regards to monitor plugins.
I implemented something in pvIOCJava but again no one bought in.
So for now pvDatabaseJava does nothing for monitor plugins.

For now the only way to get pvDatabaseJava is to get it from the

mercurial repository.

Hope this helps.

Also if you are implementing pvAccess client code then please look at

easyPVAJava.

It is part of the latest V4 release.
easyPVACPP is currently under development.

Marty Kraimer

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System