Re: Strategic Java Usage/Productivity

Bruce,

Quite a while ago, I wrote a set of procedures that dynamically built
maintenance screens in RPG -- one component was the database piece I
described in an earlier message. That framework took a couple of
thousand hours to build. It worked well, but Java is much better suited
to this. The same thing in Java took a couple of hundred. The biggest
problem with any system like this is that to get any real productivity
boost, you have to work from meta-data and there is no standard meta
format. Technologies like JSF try to address this. I have come to
realize that most programmers tend to like to write code rather than
maintain meta-data and plugin components, regardless of the productivity
boost. Ownership helps, however there are not many programmers that want
to put in the time to build meta-data driven frameworks.

David Morris

>>> brucej@xxxxxxxxxxxxxxxxxxxx 3/19/2004 9:02:41 AM >>>
A couple of examples that compare RPG  to Java/OOP.
1. Servlet containers such as Websphere and Tomcat allow people to
program
servlet according to a set of interfaces. We implement HttpServlet
class and
talk to Request and Response interfaces. That it. This brings
productivity
and system efficiency.
RPG cannot do this. RPG CGI is awkward to code and inefficient to run.

2. Someone stated that thousands of subfiles out there are doing the
same
thing. I think this is true. For each subfile one has to deal with
ROLLUP(26) ROLLDOWN(27), PUTRETAIN, DSPATR,   PUTOVR etc. etc. Then one
has
to hard wire this subfile to a RPG program that is hard wired with
database
access code and data display code. Very low productivity.

OOP allows people to program to interface.  This makes it very easy to
separate and reuse code according to functions such as presentation
and
business logic. An example is Eclipse project. People have written
hundreds
of applications for it. To add an application to Eclipse one only needs
to
drop the application folder to a folder in Eclipse. No programming and
no
configuration.
RPG cannot do this. It has no OO capability to handle this kind of
flexibility, extensibility, and pluggability.

3. Even  used as procedural programming language, Java is far superior
than
RPG. With 6,000+ classes, Java offers numerous utilities and many
frameworks. As of V5R2, RPG has only a few dozen simple built in
functions.
4. RPG may perform better. This is of importance only in isolated
situations. Besides, computers are getting faster daily. Today's
computers
are several orders of magnitude faster than they were ten years ago.

5. Suggestion: use Java as the norm and RPG as exception.