RE: JAVA400-L Digest, Vol 3, Issue 17

[murali dhar <hydchap1@xxxxxxxxx>]

Determining AS400 file descriptions or any file description is set only once by 
programmer by using files classes(the file descriptioon is keyed in manually).
The files classes  in CVS use introspection to interrogate the file class set 
up by developer and build and interface classes on compilation.The interface 
classes are used to build the SQL statement. So technically this is platform 
independent as the classes doesnt know it is AS400 it is referencing.


Joe Pluta <joepluta@xxxxxxxxxxxxxxxxx> wrote:
> From: murali dhar
> 
> We use a proxy that uses pure sql requests and have the option of
using
> proxy files which uses introspection to determine AS400 file
description
> so there fore its truly platform independent..

You may want to stop using buzzwords in your posts and start just
telling us what the software does. The buzzwords are conflicting.

For example, how does introspection make SQL more platform independent?
Introspection is used on classes, so how can introspection determine the
fields of a file? Unless you are performing introspection on a JTOpen
class such as the AS400FileDescription, at which point you are LESS
platform independent, not more.

It seems you want to use pure JDBC in order to access your data. That's
a reasonable approach in fairly trivial applications, but it's slower as
you've already seen. A better solution in many cases is stored
procedures; and for the iSeries the best is to use a message-based
server solution communicating with an RPG back end. This is what I do.

In any case, the real trick of platform independence is NOT to use the
lowest common denominator (JDBC). The real trick is to build
intelligence into your application and use some sort of configuration
file to allow you to use the best possible component for each part of
your application.

But, back to your original question, my guess is that you want to
somehow access QTEMP files with JDBC. That means you need to use the
same job for the JDBC requests as you do for the programs you call that
build the temporary files. I have no idea how to do that.

Joe

-- 
This is the Java Programming on and around the iSeries / AS400 (JAVA400-L) 
mailing list
To post a message email: JAVA400-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/java400-l
or email: JAVA400-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/java400-l.


                
---------------------------------
Do you Yahoo!?
 All your favorites on one personal page ? Try My Yahoo!