RE: Beyond RPG CGI -- WEB400

I've spent the last 18 months in an on-again off-again effort to learn Java.
There are several reasons for this move (which I'll not expound upon here),
but it has been a long road mostly because I keep getting dragged away on
other projects, one of which has been a very successful RPG-CGI project.  In
the last month however, I have been able to pretty much devote full effort
to solidifying and actually applying my Java skills to a live project.  I'm
fairly confident now in my general Java abilities with a firm understanding
that there is a lot more left to learn than I ever will.

With that as my preface, here is some free advice... just remember you get
what you pay for :-)

1.  Understand that Java is way more than just another programming language,
it is really a platform (or a sub-platform).  This platform is extremely
broad and encompasses more specialties than you can shake a stick at!
JSP/Servlets are just one area that people tend to focus on and is probably
the most visible these days.  Enterprise Java (J2EE) also referred to as
EJB, Mobile Java (J2ME), Java Networking (JINI), Java server programming,
Swing, Java Web Start, JDBC, Java Security, graphics development/games, and
more.  The common element with all of these is J2SE - the Java 2 Standard
Edition API Specification which can be found at
http://java.sun.com/j2se/1.4/docs/api/index.html.  If you are going to do
anything with Java this link will become your most valued resource, so learn
it live it love it!

2.  If you are going to learn Java, then I suggest you learn Java... what I
mean by this is that many people start off trying to use an IDE such as
VisualAge for Java, JBorland, or Forte Community Edition.  I'm not saying
anything against any of these products, I just think they are inappropriate
for beginners.  My recommendation is that you learn how to write code in
Notepad, Wordpad (my favorite) or some other basic editor first.  Learn how
to compile programs in a DOS console.  Learn how to manipulate your
classpath.  Learn how to use the above mentioned API to find classes and
solutions for yourself.  Using an IDE will let you accomplish these goals
without understanding how they work, a situation you'll soon regret when
things don't go your way.

3.  I've read a dozen books, been to several seminars, and visited more
websites than I can remember concerning Java.  The one drawback to almost
all of them is that the examples used tend to be inadequate.  I think quite
honestly that doing is the only way to learn, and playing with the examples
in a book are good to a point, but they only teach you two things: how to do
what the author wants you to see and how to copy someone else's code.  Both
of these are fine to a point but what isn't taught is how to solve problems
for yourself with Java.  One nice exception to this is the JavaRanch
Cattledrive.  It sounds hokie but is in fact an extremely effective course
of instruction online.  I cannot recommend enough that if you seriously want
to kick start your Java knowledge you should take this course.  The best
thing is that it is entirely at your own pace and you get one-on-one
feedback from some very knowledgeable people.  Check it out...
http://www.javaranch.com/drive/about.jsp (and NO, I am NOT affiliated with
this organization except as a student).

4.  Personally (and I'm putting an umbrella over my head to protect myself
from the coming hailstorm) I would avoid WebSphere.  There is nothing you
need for Java that you can't get for free on the web.  All the development
tools are free, upgrades are free, Tomcat is free (for serving your
JSP/Servlets), and even JBoss is free (for EJB).  Avoid the additional
complications of WebSphere until your company really decides it is the best
way to spend 5 figures.

5.  READ.  There have been several books written about Java for RPG
programmers.  Mostly I would avoid trying to compare the two, but there are
some useful analogies.  The one I would recommend is Don Denoncourt's "Java
Application Strategies for the iSeries and AS/400".  After a quick gloss
over to understand the commonalities get a real Beginner's Java book.  The
best and most exhaustive of these by far is "Beginning Java 2" by Ivor
Horton.  Get this book and never let it leave your desktop, I use it as much
as I use Cozzi's "The Modern RPG IV Language".

6.  You are way ahead of the game learning JSP/Servlets if you already know
CGI.  Servlets are really CGI in Java.  JSPs are a different animal but are
very simple and elegant.  Either of these can be used stand alone or
together, it's simply a matter of architecture.  There are more resources on
the web and in print for JSP/Servlets than you could ever read and I think
you could probably make a fairly rapid transition with just a small amount
of basic Java under your belt.

7.  Finally, from one RPG programmer to another... learn JDBC early.  Unlike
RPG where the first thing you learn how to do is utilize the database,
Database access is one of the last things you learn in PC land.  This will
be very frustrating when you start because in order to perform a simple data
retrieval you will be expected to understand OO, classes, classpaths, .JAR
files, and just about everything else... but there is hope: you can
successfully copy code from many resources that will at least get you
started (look at Denoncourt's book mentioned above for a good tutorial on
JDBC and the 400.

I hope this wasn't too long... there is a ton more I could say about this.
The last thing I would recommend is that if you are going to try this,
commit an appropriate amount of time to your staff and yourself to really
learn the basics... you won't regret it!


Joel R. Cochran
Director of Internet Services
VamaNet.com
(800)480-8810
mailto:custservice@vamanet.com

> -----Original Message-----
> From: Mike Skvarenina [mailto:mskvarenina@usa.net]
> Sent: Friday, March 29, 2002 9:45 AM
> To: web400@midrange.com
> Subject: [WEB400] Beyond RPG CGI
>
>
> This is a multi-part message in MIME format.
> --
> [ Picked text/plain from multipart/alternative ]
> I hope this isn't a mistake to ask this (fearing many
> different answers and opinions) but here it goes:
>
> My shop has been doing RPG CGI development for about a year
> now.  We started off with Brad Stone's book to get our feet
> wet then discovered CGIDEV2 which made the development
> process very simple.  Management however, although very
> impressed with our browser interfaces (they hated the green
> screen dubbing it "old technology"), still believes RPG is
> dead and is insistant we move away from RPG in general...even
> if it can 'work the web'.
>
> So my question is, what is your shop doing beyond RPG CGI?
> One area I am seriously considering is firing up our
> WebSphere server and learning to use it and Java.  If this is
> the right direction, what's the best way for a staff of RPG
> programmers to get started?
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