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Posted to users@tomcat.apache.org by David Wall <d....@computer.org> on 2006/06/22 20:19:07 UTC
Retrieving List from a request/session attribute
Is there a correct way to retrieve a typed List from a request/session
attribute? The attribute is returned as an Object, but using a cast like:
List<MyType> var = (List<MyType>)request.getAttribute(name);
results in a warning:
Type safety: The cast from Object to List<MyType> is actually checking
against the erased type List
The code works fine, but I'd like to get rid of the warning if there's a
correct way to do this cast.
Thanks,
David
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Re: Retrieving List from a request/session attribute
Posted by Leon Rosenberg <ro...@googlemail.com>.
On 6/22/06, David Wall <d....@computer.org> wrote:
> Is there a correct way to retrieve a typed List from a request/session
> attribute? The attribute is returned as an Object, but using a cast like:
>
> List<MyType> var = (List<MyType>)request.getAttribute(name);
>
> results in a warning:
>
> Type safety: The cast from Object to List<MyType> is actually checking
> against the erased type List
>
> The code works fine, but I'd like to get rid of the warning if there's a
> correct way to do this cast.
No :-)
At least not until J2EE 1.5
regards
Leon
P.S. You can switch this warning off.
Leon
>
> Thanks,
> David
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RE: Retrieving List from a request/session attribute
Posted by Martin Gainty <mg...@hotmail.com>.
David--
Personally...I would use reflection...
try
{
List<MyType> var = Class.forName(request.getAttribute(name));// get class
definitions
o = var.newInstance(); //Instantiate a new class using the class(and
consequent definitions)..
}
catch(Exception excp)
{
System.out.println("Didnt like the class ..message="+exp.getMessage());
}
HTH,
Martin --
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>Subject: Retrieving List<MyType> from a request/session attribute
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>
>Is there a correct way to retrieve a typed List from a request/session
>attribute? The attribute is returned as an Object, but using a cast like:
>
>List<MyType> var = (List<MyType>)request.getAttribute(name);
>
>results in a warning:
>
>Type safety: The cast from Object to List<MyType> is actually checking
>against the erased type List
>
>The code works fine, but I'd like to get rid of the warning if there's a
>correct way to do this cast.
>
>Thanks,
>David
>
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