General Persistence Implementation Strategy Question

Hi,
I want to implement a J2EE application and use a persistence system like Hibernate. I will have to create several beans and set-up my ORM properly. Now, if I create an Enterprise project in NetBeans, where should I put my Peristence code? In a Web container or in a EBJ container knowing that both JSP pages and EJB will refer to my persisted beans? Or should I create another separate project and include the corresponding .jar in both my Web or EJB containers?
What is the best strategy?
Thanks,
J.

Jrm wrote:
Hi,
I want to implement a J2EE application and use a persistence system like Hibernate. I will have to create several beans and set-up my ORM properly. Now, if I create an Enterprise project in NetBeans, where should I put my Peristence code? In a Web container or in a EBJ container +
knowing that both JSP pages and EJB will refer to my persisted beans+? I would say that JSPs should not be contacting your database directly. Better to go through a well-defined service layer that hides the persistence layer. All security, binding, and validation issues should be resolved before the service layer is called.
Or should I create another separate project and include the corresponding .jar in both my Web or EJB containers?Both? Wrong.
%

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hai friends,
could anyone help with the
'implementation strategy for non sap sources'.

Hi,
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Thank you!

anotations and classes is in javax.persistence
package. What is that package, where it come from? Is
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The specification:
http://jcp.org/en/jsr/detail?id=220
Persistence Part in JavaEE 5 Tutorial (Part Four: Persistence )
http://java.sun.com/javaee/5/docs/tutorial/doc/
In fact I would
like to use Persistence API on sites managed by
Apache Tomcat Server. Is it possible, what classes do
I need? Another question is it is possible to use
that API at Swing Applications, and what do I need to
do this. They are all possible ways of using JPA. See JavaEE 5 Tutorial for more details. The newly released NetBeans 5.5 has nice support for developing and deploying JPA applications. NetBeans site has a lot of resources on this topic. For example:
http://www.netbeans.org/kb/55/persistence_ontomcat.html
http://www.netbeans.org/kb/articles/hibernate-javaee.html
-cheng

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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Kito D. Mann
[email protected]
Virtua, Inc.

In regards to my third point:
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Kito D. Mann
[email protected]
Virtua, Inc.

General benefits implementing BO against SAP-BI.

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2- (Deleted -> see the [integration forum|Benefits implementing BO over SAP-BI.;)
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4- (Deleted -> see the [integration forum|Benefits implementing BO over SAP-BI.;)
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Please, do not hesitate in request more info from my side, and answer just one or some of the 5 questions, and any other question that could be useful.
Use links if necessary.
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PS:
Ingo's 9 first blogs: BusinessObjects and SAP Part 9 - Xcelsius with Crystal Reports and Live Office
Edited by: Zorion on Nov 18, 2008 7:45 AM - Separate the SAP's part into the integration forum

Thanks for your reply, Falk.
I did read some "getting started" documents but I did not find anything what can't be done easily with SAP-BI or MS excel, so I assumed that I was checking the wrong documents.
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Hello,
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Keshav has already outlined required logic, so let me fulfill his answer with a snippet
An Interface
INTERFACE lif_payment.
METHODS pay CHANGING c_val TYPE p.
ENDINTERFACE.
Payment implementations
CLASS lcl_payment_1 DEFINITION.
PUBLIC SECTION.
INTERFACES lif_payment.
ALIASES pay for lif_payment~pay.
ENDCLASS.
CLASS lcl_payment_2 DEFINITION.
PUBLIC SECTION.
INTERFACES lif_payment.
ALIASES pay for lif_payment~pay.
ENDCLASS.
CLASS lcl_payment_1 IMPLEMENTATION.
METHOD pay.
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ENDMETHOD.
ENDCLASS.
CLASS lcl_payment_2 IMPLEMENTATION.
METHOD pay.
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ENDMETHOD.
Main class which uses strategy pattern
CLASS lcl_main DEFINITION.
PUBLIC SECTION.
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    METHODS pay.
PRIVATE SECTION.
    DATA payment_value TYPE p.
    "reference to your interface whcih you will be working with
    "polimorphically
    DATA mr_payment TYPE REF TO lif_payment.
ENDCLASS.
CLASS lcl_main IMPLEMENTATION.
METHOD constructor.
    IF ir_payment IS BOUND.
      me->mr_payment = ir_payment.
    ENDIF.
ENDMETHOD.
METHOD set_payment.
    IF ir_payment IS BOUND.
      me->mr_payment = ir_payment.
    ENDIF.
ENDMETHOD.
METHOD show_payment_val.
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ENDMETHOD.
"hide fact that you are using composition to access pay method
METHOD pay.
    mr_payment->pay( CHANGING c_val = payment_value ).
ENDMETHOD.                   ENDCLASS.
Client application
PARAMETERS pa_pay TYPE c. "1 - first payment, 2 - second
DATA gr_main TYPE REF TO lcl_main.
DATA gr_payment TYPE REF TO lif_payment.
START-OF-SELECTION.
"client application (which uses stategy pattern)
CASE pa_pay.
    WHEN 1.
      "create first type of payment
      CREATE OBJECT gr_payment TYPE lcl_payment_1.
    WHEN 2.
      "create second type of payment
      CREATE OBJECT gr_payment TYPE lcl_payment_2.
ENDCASE.
"pass payment type to main object
CREATE OBJECT gr_main
    EXPORTING
      ir_payment = gr_payment.
gr_main->show_payment_val( ).
"now client doesn't know which object it is working with
gr_main->pay( ).
gr_main->show_payment_val( ).
"you can also use set_payment method to set payment type dynamically
"client would see no change
if pa_pay = 1.
    "now create different payment to set it dynamically
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    gr_main->set_payment( gr_payment ).
    gr_main->pay( ).
    gr_main->show_payment_val( ).
endif.
Regads
Marcin

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   ||                  ||                  ||
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Alex Zetune
Gold Strategy Solutions
az AT goldstrategy.com

Hello Alex,
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Thanks again
*Edit*
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Firefighter Implementation Strategy

Hello All,
We are implementing Firefighter in our landscape, and we want that all changes in SAP system should be done with Firefighter, but to reduce the usage of Firefighter we would be using our existing normal users for Daily Checks and monitoring without any change.
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Regards
Davinder

Davinder,
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Simon

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I have a really vague question about interfaces....can't really figure out how this works...I know that interfaces only have method definitions and the implementing classes should define those methods.
I am trying to use a DOM parser to parse an XML document. The org.w3c.dom package gives you a list of interfaces like Node, NodeList, Document etc to work on.
Assume that i have the following code in my class:
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
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NodeList itemList = doc.GetElementsByTagName("item");
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Here is what I dont understand...doc is of type Document which is an interface. Yes.
How can you call the method of an interface directly in the 4th line? How? Just like that.
I thought we are only supposed to call methods on the implementing class...Methods are applied to objects, not classes.
the problem is I dont see an implementing class here...And you don't need to. Do you need to open up your DVD player and look inside in order to push "play"?
does the builder.parse(invoiceXML) return a Document interface or an object that implements the Document interface? Methods don't return interfaces. They return references to objects (or primitive values).
If 'doc' is actually an object that implements the Document interface then it makes sense here...Eureka!
but then will all the methods be automatically implemented in the object created by the api?"Automatically" is not how to think about it. The Document interface was implemented by some class, the details of which aren't important. What's important is that if you have a reference to an object of type Document, you can apply Document methods to it, according to the API for Document.

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BamaColtsFan wrote:
Hey Gang,
I know that the general rule here is to try your code first then ask why it doesn't work but my questions right now are more conceptual than anything else. I know a little (very little, really) about Java and some of it's capabilities. I've been thinking about possibly converting a MS Access Utility that I use into a Java program. The MS Access version can be a little unstable and I think by moving to Java, I can eliminate that problem. But, I want to be sure that Java can do everything I need it to do before I spend a lot of time only to find I can't get there from here. These are my initial questions:
1. I have to run several reports from a large Oracle system. Currently, I export the data as Excel files and link the Access database to them. Using Java, will I be able to export as text files (daily) and have the program read the text and treat it like a database file? The short answer is NO. The more lengthy answer is yes, but you can attach to Excel spreadsheets through ODBC (JDBC/ODBC Bridge) and use them as a database the same way Access did.
2. Part of the output of the Access database feeds MS Word mail-merge documents that are used to send e-mail messages. Will Java format and send e-mail via Outlook? NO, but you can send mail with the Java Mail API.
3. The second half of the output is an Excel Workbook with re-formatted and cleaned report data from the original files. Can Java dynamically pass information to Excel and create the various worksheets necessary to display the data the way management wants to see it? NO
Now having said all of that, there is the Java interface through OpenOffice, which will support MS-Office documents. The MS Office products are Windoz specific, and as such, there are some 3rd party Classes out there that will interface to them, but not directly from Sun's standard API.

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