Hello All,
In the past few days I have been struggling to understand how exactly Session EJB's (remote interfaces) and Entity EJB's (local interfaces) communicate. I have read up on JNDI which seems to be the way to go, but I there is still a few things unclear to me.
I have created a simple session bean Catalogue. Now I have created a method in Catalogue to lookup my Entity Beans so that I can use them for my business logic. The following method provides, what I think, could be used to obtain a reference to a Entity Bean. I am using CMP, so if that makes any difference in terms of lookup code I would be glad to hear about it.
// Lookup my entity beans
public void lookupEntityBeans () throws NamingException {
Context ctx = new InitialContext();
Account accountEntity = (Account)ctx.lookup("Account");
Part partEntity = (Part)ctx.lookup("Part");
}
Now from my Catalogue Session Bean, I wish to a get the discount which is associated with a particular customer, which is stored in the Account Entity Bean. Upon retrieving that value I would store it in a local variable. Then get the price of a particular part from a Part Entity Bean and store it in a local variable as well. Then perform my business logic using the values I have extracted from the 2 entity beans.
// Business Method
public double computeNewPartPrice (double oldPartPrice) {
// getPartPrice is an abstract method defined in
// the local interface
oldPartPrice = partEntity.getPartPrice();
tempAccountDiscount = accountEntity.getAccountDiscount();
newPartPrice = oldPartPrice - tempAccountDiscount;
}
Question 1
Basically, is the above code listings enough to get the necessary information that I need from the entity beans?
Do I need to declare any JNDI context code in my entity beans or is that done by the container?
Question 2
If I want to find say a customer discount value, which is located in the Account Entity Bean, should I use the findByCustomerID(String custID) method OR is it taken care of for me as suggested by Mastering EJB?
Question 3
If I use CMP Entity Beans, do I still need a AccountPK class OR is that taken care of by the container as well?
Thanks
Discussions
EJB programming & troubleshooting: Newbie : How to communicate between Session EJB and Entity EJB
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Newbie : How to communicate between Session EJB and Entity EJB (1 messages)
- Posted by: Izak Wessels
- Posted on: December 29 2003 12:19 EST
Threaded Messages (1)
- Newbie : How to communicate between Session EJB and Entity EJB by ashish verma on December 30 2003 20:00 EST
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Newbie : How to communicate between Session EJB and Entity EJB[ Go to top ]
- Posted by: ashish verma
- Posted on: December 30 2003 20:00 EST
- in response to Izak Wessels
Have a look at this tutorial and should explain yr queries.
www.tusc.com.au/tutorial/html/chap3.html
Cheers...
Vishal.