Re: Effort to program in Java, is it efficient....

> In broad terms can Java be implemented in a simple
> manner and does that make sense in a lot of cases.

Mike,

I'd suggest that using Servlets as a conduit between business logic and JSPs
is pretty simple, and does make sense in many cases, particularly
e-commerce.

> How does the JAVA language/environment stack up
> to other technologies?

Wouldn't that depend on the application?  Users submitting batch reports all
day might be one thing, while an e-commerce application might be another.

I think there are valid concerns about using EJB technology.  You may be
forced into it, depending on your company's attitude about cross-platform
compatibility.  Some insist that 100% pure Java is mandatory, while others
would suggest using RPG to implement business logic.  Midrange Server
magazine had an article about CMS Manufacturing Systems finalizing on a Java
+ RPG approach in their ERP suite.

Application servers like Websphere are designed for e-commerce, rather than
traditional workloads.  In e-commerce you might have hundreds or even
thousands of users accessing a relatively small number of programs and
files.

On the other hand, in a traditional environment you might have fewer users,
but they're running hundreds or even thousands of different interactive,
client-server, and batch programs, updating hundreds or even thousands of
files throughout the day.

It's unclear how a Java might perform in complex runtime environments.
Java's larger instruction sets, and significant memory requirements in
theory would lead to significant CPU cache faults under complex workloads.
Say you had 2000 Servlets competing for cache instead of 200.  With page
faults, one can always buy more memory, but processor cache is fixed.

One DP manager told of his experience where dividing a CPU between two (2)
partitions led to widely variable, terrible Websphere performance, while the
traditional workload was hardly affected.  The problem was that CPU cache
needed to be purged and reloaded as CPU time was given to one partition or
the other.

Reloading Servlets from memory to cache caused wide swings in performance,
while the reloading problem seemed to have little impact on RPG programs.
This was from a guy who is busy trying to replace every RPG program with
Java.

The question of programming effort is also related to the type of
application.  Writing a report program in RPG may take less time, but
writing a SOAP based Web service may not.  The hard part in any application
environment is coming up with your overall development framework.  Once the
framework is delineated, then putting it work is easier.  The challenge in
Java, is the large number of options available.

Nathan.