DAO and session Facade

Hi
I came across an design pattern where they call the DAO from Session facade. The purpose of session facade is to minimise the number of network calls. Even though there are no network calls involved why do they go for session facade to call the DAO. Wont a DAOFActory will help them doin this.
Even if the requirement is to block the presentation layer of all the backend operations, we could have had any other , why session facade was used i could nt understand

You might even discover that entity beans can get created even before you use them.
Your application server creates "pools" of bean instances that it can use when it needs to. It is part of this role, and is done in order to optimize performances.
You cannot force them to be garbage collected. Even if you stop referencing them, the app server will.
When your create references to a bean, it (usually) won't create an instance. It will take an existing one, and load data into it, using ejbCreate or ejbActivate.
Hope this helps.
/Stephane

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    Edited by: 992005 on 05-Mar-2013 18:17

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    in the line of fire wrote:
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    >
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    Business Delegate as well as Session Facade are used
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