Roopa,
No, in this example, Address is a "dependent object": it's not an EJB, just
a regular Java class.
class PersoneEJB implements EntityBean {
private Adress adress;
public void setAdress(Adress adress) {...}
public Adress getAdress() {...}
}
The Aggregate EJB manage a graph of parts. The parts are regular Java
classes.
Another example is Invoice and InvoiceLine. An invoice line is a dependent
object because it's life cycle is controled by the Invoice object itself.
class Invoice implements EntityBean {
private List invoiceLines;
public void addInvoiceLine(InvoiceLine line) {...}
public void remInvoiceLine(InvoiceLinePK pk) {...}
public void changeInvoiceLine(InvoiceLinePK pk, InvoiceLine line) {...}
}
Then, the Invoice EJB can recompute the invoice total when the invoice
lines are changed.
InvoiceLine is a tto fine grain object to be distributed.
Have a look on the Craig Larman's article.
http://www.sdmagazine.com/articles/2000/0004/0004c/0004c.htm
Hope this help.
Tibo.
>-----Original Message-----
>From: roopa kotha [mailto:[EMAIL PROTECTED]]
>Sent: Wednesday, January 03, 2001 3:47 PM
>To: [EMAIL PROTECTED]
>Subject: Coarse grained EJB
>
>
>Hi Thibault,
>
>I got your email Id from ejb mailing list.
>
>I had a question regarding coarse grained EJB
>
>2- Create BIG, coarse grained EJBs.
> - Represent an aggregat of data stored in different tables
> - i.e.: PersoneEJB with a method getAddress
>
>Does this mean in a CMP entity bean you have getAddress method
>which talks
>to the Address CMP entity bean.
>
>Can you explain this bit more
>
>Thanks
>Roopa
>
>
>
>There is 2 granularity problem when you design Entity EJBs:
> - Component granularity
> - Accessors granularity
>
>
>1-- Component granularity
>---------------------------------
>There is two extrem solutions when you create EJbs
>
>1- Create small, fine grained EJBs.
> - Usually, you create 1 EJB per table
> - i.e.: PersoneEJB and AddressEJB
>
>2- Create BIG, coarse grained EJBs.
> - Represent an aggregat of data stored in different tables
> - i.e.: PersoneEJB with a method getAddress
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