topic Re: persistent class in Application Development and Automation Discussions

persistent class

Former Member — Thu, 06 Oct 2005 05:52:00 GMT

<b>hi

any body tell to how to do the persistent class in my own object for ex (icl_airplane)., how to retrieve the object data to my program.,

Regards

K.Gunasekar</b>

Re: persistent class

Former Member — Thu, 06 Oct 2005 05:58:53 GMT

if you mean the persistent class which combine with a table, and offer the method to manipulate the record in table, if only available on WAS 6.4.

here is a link to guide you how to use it:

https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/840ad679-0601-0010-cd8e-9989fd650822#q-20

hope it will be hepful

thanks

Re: persistent class

Former Member — Thu, 06 Oct 2005 19:23:06 GMT

Hi,

there is also a Weblog from Thomas Jung at /people/thomas.jung3/blog/2004/12/08/abap-persistent-classes-coding-without-sql

I have take a look to this concept on a WAS 6.20.

A Agent class manage the references from persistence classes.

This means that you call a method from the agent with the business key and get back a reference for the persistence class.

Now you can call a GET-method for every attribute (field) to retrieve the value or call a SET-method for every attribute (field) modify the value from this persistence class.

I tried to expand a SET-Method with a validity check.

But when I generate the Persistence class again, my code is deleted :-(.

Zhenlin Gu wrote me in another post, that it's possible to make a work around by using the persistence class as a superclass.

Could somebody in this forum tell us a more about his experience with the persistent classes?

Regards,

Stefan

Re: persistent class

Former Member — Fri, 07 Oct 2005 02:00:01 GMT

hi, Stefan Gerschler

You still remeber me and the question on regenerate Pesistent Class, hehe

'more about his experience with the persistent classes?'

What's that means? you need another way to solve that problem on regenerate?

thanks

Re: persistent class

Former Member — Fri, 07 Oct 2005 06:36:36 GMT

Hi Zhenglin gu,

thanks a lot , your work around should work.

And the post remembered me that I haven't reward you your points - I have done it now, sorry for the delay.

My problem is now that i am not sure if it is a good idea to use the persistence classes for a development

with mass data. Do the agent hold the references the whole job run? Then the memory will be overflow.

The persistence classes are still a "black box" for me and I am afraid of problems to use them.

Regards,

Stefan

Re: persistent class

Former Member — Fri, 07 Oct 2005 09:35:06 GMT

hehe, Stefan Gerschler

I don't mind your delay. Actually there are many answers I posted and accept no rewards. hehe but the reward points is not the only thing for me to SDN.

And about the Persistent Class, I remeber in Visual Studio, microsoft also offer a mechanism like it. But I think it is not popular, even many people don't know it.

Persistent class is a new feature in ABAP world, so I think maybe it won't be perfect on it, and I think some change will be done by sap in the furture, if they don't abandom it. hehe who know.

I don't know the cost of holding a Persistent class, haven't do a research, if not large, maybe you can create them every time you use it. If won't to plan it very soon, maybe free it.

glad to discuss with you on this topic

thanks