Hey James:
I am not in total agreement with Thorbjørn, but I can't say I disagree either.
My take ... version 3 of EJB is getting traction and has good feedback ... third time is the charm. But most things that really use EJB are big framework applications which involve buying into the framework and buying tools. I wouldn't write them off.
The basic technology for talking to databases is "JDBC" which is
essentially a tunnel allowing you to send SQL-statements and get the
answers back.
I agree. If your only database engine is an i5 then consider the jtOpen direct file access tools. In some cases, especially considering your background, using these will be more efficient. On one hand these classes are more like what you already know how to use. They can be more efficient with big, complicated database relationships. On the other hand using these classes puts off learning other persistence options.
I would suggest that you create a small application with
JDBC to learn how it works because you need to know when using
frameworks that do persistence because you WILL need to debug some day...
I can't say I disagree however I would suggest going directly to JPA (Hibernate or Eclipselink) or iBatis instead of learning JDBC in depth unless you will be working with apps that use JDBC which you have to maintain.
JDBC is too close to the metal. There is a lot of coding, condition handling and resource management. This is done for you with JPA or iBatis. You deal with it at a higher level and let JPA/iBatis take care of the details.
Regards
Bill Blalock
-----Original Message-----
From: java400-l-bounces@xxxxxxxxxxxx [mailto:java400-l-bounces@xxxxxxxxxxxx] On Behalf Of Thorbjørn Ravn Andersen
Sent: Tuesday, October 21, 2008 4:52 PM
To: Java Programming on and around the iSeries / AS400
Subject: Re: Understanding Object Usage
James Perkins skrev:
totally pleased with it. Out of curiosity would you suggest EJB's or
EJB's were basically created to allow a Java application to
transparently call Java code running in _ANOTHER_ Java virtual machine.
Don't go there unless you really have to!
The basic technology for talking to databases is "JDBC" which is
essentially a tunnel allowing you to send SQL-statements and get the
answers back. I would suggest that you create a small application with
JDBC to learn how it works because you need to know when using
frameworks that do persistence because you WILL need to debug some day...
/Thorbjørn
midrange.com
