Re: Web5250 Business Developers was ->Re: IBM Gives RPG Devotees Their Own Café

I haven't tried to "scale" it. It would probably be similar to having tn5250j on the desktop with many sessions open. Haven't looked into the internals of 5250j to see if there are limits. Probably should take a look at the "expense" of each connection. I only have to deal with one object in tn5250j, the 5250 protocol bean, all of the other stuff I am insulated from so it might take some digging to unpack all of the issues.

Much of this was written early on in the AEE development cycle Nathan. We eventually settled on using the tn5250j applet because it was more stable and complete. I saw Joe's post about PSC and I wonder if something very similar to web5250 could be written in RPG. It would probably be something worth investigating. The biggest issues I had were with function keys that triggered browser functions, rather than the 5250 functions but I was a complete noob with Java, Javascript and css (which could be helpful) so there are probably better approaches I could take now. I need to blow the dust off of this I guess. I haven't had much interest in the project although I get a connection or two under the Demo userid every week.

Pete


Nathan Andelin wrote:

From: Pete Helgren>
I built [a] prototype which is really just a very thin layer
(well, not thin enough for Nathan!) over the top of tn5250j.

Moving tn5250j to the server seems like a good idea. That way, each workstation doesn't have to run its own set of applets and associated JVM.

The design also provides a way to run JavaScript on the browser to extend the interface. My main concern is the type and amount of HTML that web5250 generates.

Hence the suggestion to write a JavaScript client, and work with smaller data streams. Niels suggested a JSON formatted streams. That sounds fine to me.

I'm still curious how tn5250j works as a server? I've always thought of it as a single user client. You've come up with a way for multiple browsers to connect to a single servlet? And manage multiple concurrent connections?

Anyway it sounds like some of your TODOs could be solved by a JavaScript client - better support for function keys, for example.

Nathan.