Re: How hard is Java, really? -- WEB400

From: albartell

I have not used your PSC product - maybe someday.

This is not specific to PSC. It's specific to the concept of a thin JSP
layer. My point is only that PSC uses this architecture to deploy thousands
of JSPs using a single servlet.

When you came into my
previous employer you showed us a way to develop NEW non-DDS web programs
that calls for a .jsp AND .java file for each page (.jsp did the
connecting
back the .java bean where the conversion was done). So maybe we are
talking
about completely different scenarios here??

NO! It's the exact same thing I was teaching then (and which has been
successfully used by others).

The Java bean simply had the field definitions, which is the three line
change I laid out in my previous message. The bean is butt simple to
maintain -- certainly just as easy as maintaining the RPG-CGI program and
adding an updHtmlVar call. When I was out there, I even explained how the
bean could be generated from an externally described data structure.

My point is that it's just as hard to learn JavaScript as it is to learn

Java.

Even after reading your entire section I still don't agree that Java is
equivalent in learning to Javascript, but that may be just because I
wasn't able to pick up Java as easily as other languages.
Like another gentleman
said, Java may be easy for YOU, but not for everybody else that is trying
to pick it up.

If it was easy, they wouldn't pay us to do it. I'm just saying the fact
that you have trouble with Java doesn't make JSP a bad architecture. It
just makes it a bad choice for you personally. Java is not a bad language;
LOTS of people learn Java -- there are far more Java programmers than RPG
programmers!

And it works in reverse, too. I find Java a lot easier than Python,
personally, but that doesn't make Python bad.

I think you need to look at it from the standpoint of
understanding NOTHING about the environment. You need to think about what
the average RPG programmer would have to do to write programs with Ruby On
Rails. Learn the language, learn the IDE, learn the app server, learn the
MVC implementation concepts, etc.

The ONLY reason you can get away with this at all is because somebody wrote
CGIDEV2 for you. If you had to write CGIDEV2 from scratch, you probably
wouldn't be so thrilled with RPG-CGI. And by the same token, if you had a
framework like mine and you could pick up the language, you'd find that it
would be just as easy as CGIDEV2. Again, the argument seems to come back
consistently to the fact that you don't like Java.

And I haven't even addressed the myriad benefits of having the web

interface portion of your architecture be platform independent.

I would rather have everything on one box and be locked into the System i.

That's you. Many people would rather not waste precious System i cycles on
essentially converting EBCDIC to ASCII. That's a business decision, not an
architectural one.

Do I have Java code that runs on Wintel, you bet, but that was because I
wrote it for resale and I couldn't require a non-iSeries shop to buy an
iSeries simply because my app required it. That maybe is a key difference
here. If you already own an iSeries and have RPG knowledge then doing RPG
CGI is very appealing and would definitely be my first choice.

Again, that's a business decision. If you know Java, then JSP is a piece of
cake. You don't like Java, so you don't like JSP. Leave it at that.

I won't argue the increased performance because we all know System i5
hardware is not cheap (though you lose ease of hardware maintenance
complexity - two machines now), but how does having your UI layer in a DMZ
with i5 DB2 behind the firewall (the approach I am guessing you are
recommending) benefit your architecture when the communication from the UI
layer is done through data queues and the System i5 has object level
security?

Simplest answer? DOS attacks.

If your primary business machine has no Internet connection, it cannot be
affected by Denial of Service.

Joe