Re: Calling ILE from Java

Aaron Bartell wrote:

That PCML feature coupled with RPG's new thread safe capabilities would make
the perfect case for an RPG Application Server (RAS - I said it first :-)

I've been calling it a business logic server, but that's neither here nor there. Plus, I think you still have the server/client architecture in your mind, where the server tells the client which window to display. That actually works pretty well for page-at-a-time web designs, but for Web 2.0, with AJAX and RESTful services, you're probably going to need a more traditional client/server approach, where the client makes a request and the server processes it.

Either one, though, is supported by a routing mechanism such as the one you're talking about.

over HTTP that allows for persistent connections that don't have to start a
new job for each connection and instead maintain a persistent thread.

That's what you want. This is the part you may not like, though: the easiest way to implement this is via a J2EE web application server. All the support for persistence, security, failover, etc. are all already written within the J2EE layer. All you have to do is match that up with a QZRCSRVS job which acts as your request router. And seriously, I don't think you need threads in i5/OS, just dedicated jobs. You start the job when the user authenticates and end it when the user logs off or times out.

Based
on a token sent from the client, a router type program should be able to
spawn and match up request and response communications to/from threads. I
am not well versed in application server guts so a lot of this is "brain
storming statements" that may or may not be feasible. Joe, any comments on
the usefulness or possibility of such a server?

I think it's a great architecture. I have clients who do this sort of thing already, some of them using what they call "the Pluta Pieces", which are the basic plumbing between J2EE and ILE. What's gonig to make this really cool, though, is the availability of the IAS (the Integrated Application Server) running on an i5/OS blade server. In that configuration, you can basically plug in a business logic server that responds directly to HTTP requests - how the requests are formatted is up to you. They can be simple REST/JSON requests, web services, whatever.

Or, you install a web client that runs on the IAS and you've got a complete self-contained web app.

Joe