On Mon, Apr 27, 2009 at 12:09 PM, Georg Füchsle <[email protected]> wrote:
> Thanks Matthias,
>
> I do not use EL API, and I don't understand what you mean by DI-container.
in fact, you are using the API:
javax.faces.el.ValueBinding vb =app....
cleaner solution is using some DI container
(e.g. spring)
>
>
> But I can show you the following example:
>
> I have an application scoped bean and a session scoped bean (MbSessionBean)
> In my application scoped bean I found code like that:
>
> public String getImageUrl()
> {
> int layout =
> (MbSessionBean)getManagedBean("mbsessionbean").getLayout();
>
> if(layout == 1)
> return "/pages/imageone.jpg";
> else
> return "/pages/imagetwo.jpg";
> }
>
>
>
> protected static final Object getManagedBean(String beanName)
> {
>
> Object ob;
> FacesContext facesContext = FacesContext.getCurrentInstance();
> Application app = facesContext.getApplication();
> javax.faces.el.ValueBinding vb
> =app.createValueBinding("#{"+beanName+"}");
> ob = vb.getValue(facesContext);
> return ob;
> }
>
>
>
> Of course this is not nice code, because I ask user dependent data
> from a method of an application scoped bean.
> But I wonder how it can work.
>
> How does the application bean know which session scoped bean it should ask?
it uses the one from the current user. Using the API like you do is a
giant hack.
I'd not do it, even it works... This code will cause errors and "fun"
in the future
of the application.
>
> Obviously it works. But does it only work by chance, ( for example
> because there has never been 2 or more session beans with different
> data at the same time...) or does it really work?
>
> If it works (even the code is ugly) I could let it this way now and
> clean it another time....
>
>
> Cheers Georg
>
>
> 2009/4/27 Matthias Wessendorf <[email protected]>:
>> I'd not do that...
>>
>> generally fetching beans by using the EL API is not that good.
>> Use a real DI container for that
>>
>> -M
>>
>> On Mon, Apr 27, 2009 at 11:22 AM, Georg Füchsle <[email protected]>
>> wrote:
>>> Hallo,
>>>
>>> I found such things in my code:
>>>
>>> In an static method of an application scoped bean I fetch a session
>>> scoped bean and read some data from it.
>>> It seems to work. But is it really allowed?
>>>
>>> Georg
>>>
>>
>>
>>
>> --
>> Matthias Wessendorf
>>
>> blog: http://matthiaswessendorf.wordpress.com/
>> sessions: http://www.slideshare.net/mwessendorf
>> twitter: http://twitter.com/mwessendorf
>>
>
--
Matthias Wessendorf
blog: http://matthiaswessendorf.wordpress.com/
sessions: http://www.slideshare.net/mwessendorf
twitter: http://twitter.com/mwessendorf
