Yea, that's pretty much what I wound up doing. I created EJBLinkedList and
EJBHashSet for this purpose. Except that instead of contains, an override
of indexOf, lastIndexOf and remove is needed, because Object.equals is used
there. But when you try to re-implement any of those functions, you get
into trouble because Entry, is a PRIVATE in LinkedList. So.... hack.....
wack, we got a EJBLinkedList that looks eerily familiar to LinkedList.
On the other hand, I think I know one of the reasons why what I suggested
did not work. The EJBObject.isIdentical() API raises a
java.rmi.RemoteException. Object.equals() API does not. Thus there are two
options, raise an EJBException, or leave it alone and do nothing. They
chose the nothing path.
-AP_
-----Original Message-----
From: A mailing list for Enterprise JavaBeans development
[mailto:[EMAIL PROTECTED]]On Behalf Of Fred Loney
Sent: Thursday, August 16, 2001 6:43 PM
To: [EMAIL PROTECTED]
Subject: Re: Why does the spec feel so strongly against defining
"equals" or"hashCode" on EJBObject?
One possibility is that a redirection architecture could use a proxy for
EjbObject that potentially fronts for the real Entity Bean. In general, the
ejb
spec is zealous about insulating the client interface from the container
implementation.
A work-around is to subclass LinkedList and override contains(), which is
admittedly inconvenient. I use value objects rather than EjbObjects to
collect
a query result in order to protect against this and other oddities.
Alex Paransky wrote:
> The EJB 2.0 spec specifically states that equals or hashCode functions are
> not defined for EJBObject. I don't understand why this decision was made.
>
> The reason I am asking, is that I just got bitten with an interesting bug.
> In one of my functions, I need to execute many finders, and put the result
> in to a single Collection. I create a LinkedList for this purpose. But
> when the client gets the Collection I return (LinkedList) and tries to use
> Collection.contains() API, it fails because LinkedList performs
> EJBObject.equals operation instead of EJBObject.isIdentical.
>
> Which leads to a fact that most operation collections in java.util become
> useless, since you can no longer say Collection.contains, or Set.addAll,
or
> use any operations which perform comparisons.
>
> Why not implement equals to execute isIdentical, and hashCode to execute
> getPrimaryKey().hashCode()?
>
> Thanks.
> -AP_
>
>
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--
Fred Loney
Spirited Software, Inc.
[EMAIL PROTECTED]
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