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Many @PostConstruct methods?

Raf Szczypiorski
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Joined: Aug 21, 2008
Posts: 383
Hi. Can a bean have many @PostConstruct methods? I creted 2, but the container always invokes only one of them (the second one defined in the file, glasssfish v2). The same for @PreDestroy. However, the specs say:
The container then calls the PostConstruct lifecycle callback interceptor method(s) for the bean, if any.

How is it, then?
Thanks.
Ralph Jaus
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Joined: Apr 27, 2008
Posts: 342
There can be at most one lifecycle callback method per lifecycle event in a class.
The following classes can contain lifecycle callback methods:

- interceptor classes and their superclasses
- bean classes and their superclasses

If a lifecycle event occurs at first the lifecycle callback methods in the interceptor classes
(and their superclasses) are called and afterwards the lifecycle callback method in the
bean class (and those in the superclasses of the bean class).

For more details concerning the invocation order and overriding see core spec 12.4.1


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Raf Szczypiorski
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Joined: Aug 21, 2008
Posts: 383
Thank you.
Joe Harry
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Joined: Sep 26, 2006
Posts: 9426
    
    2

Ralf: Here the question was as to which method out of the two marked as @PostConstruct will be invoked?


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Treimin Clark
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Joined: Nov 12, 2008
Posts: 757
Jothi Shankar Kumar wrote:Ralf: Here the question was as to which method out of the two marked as @PostConstruct will be invoked?


As I know, it is unpredictable.
Ralph Jaus
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Joined: Apr 27, 2008
Posts: 342
Ralf: Here the question was as to which method out of the two marked as @PostConstruct will be invoked?

Having more than one post-construct method (the same holds for any other lifecycle event) in one class is not compliant with the ejb 3.0 spec. So the behavoir of the system is undefinied. But if there are several post-construct methods distributed over serveral classes then the order is definied by the spec (see my post above).

 
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