December 2002
Intermediate to advanced
1050 pages
24h 49m
English
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Accessing an Entity Bean
As we know, an entity bean is an EJB that represents a unique instance of an entity in a permanent data store. Each entity bean is represented by a unique ID: a primary key. Unlike session beans, which are usually created for use, an entity bean represents persistent data and is therefore usually found and retrieved from the data store.
The previous example showed the use of JDBC in a helper object for a session bean. The helper object implemented the Data Access Object (DAO) design pattern, which isolates and encapsulates the data access activity into a coarse-grained object. By using this design pattern, the details of the data and the data access are isolated from the session facade bean.
DAOs can also have utility ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
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