struts-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From p ...@dowman.net>
Subject Re: Singletons in Tomcat
Date Fri, 06 Jun 2003 15:41:46 GMT
But if your singleton is part of your business logic, the drawback is 
that it ties that part of the application to the servlet api, reducing 
portability.

Just out of curiosity, what are the drawbacks to implementing a 
singleton with a static variable (and private constructor, etc)? then 
there will be only one per classloader, and you still have full control 
over it's lifecycle, you can remove it with a ServletContextListener 
(assuming you implemented a static "removeInstance()" method)




On Thursday, June 5, 2003, at 02:12  PM, Markus Holzem wrote:

> I usually story Singletons in the ServletContext which is unique for
> an application. I often think that ServletContext should be better
> named ApplicationContext because that is actually what it represents.
>
> I don't feel comfortable to leave Singletons hanging around on static.
> variables. The benefit of ServletContext is, that you can easily
> participate on the lifecycle of the ServletContext
> (ServletContextListener::contextInitialized and ~::contextDestroyed)
> and take appropriate actions when your Singleton acquires any system
> resources.
>
> Markus
>
> Brian Kidney wrote:
>
>> -----BEGIN PGP SIGNED MESSAGE-----
>> Hash: SHA1
>>
>> If I have a class in my application which is a singleton, is there 
>> only one object per server (Tomcat in my case), or is it unique to 
>> the session (ie. each user gets a different instance)?
>>
>> Brian
>>
>> -----BEGIN PGP SIGNATURE-----
>> Version: PGP 8.0
>>
>> iQA/AwUBPt92MuLP0vXx30WgEQKtFQCfX4gkSYSwqx9+Zij4IfQU9DxA6L4An2gY
>> hUqwLgvXo/4W5scinkxmIF7j
>> =Osto
>> -----END PGP SIGNATURE-----
>>
>>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: struts-user-unsubscribe@jakarta.apache.org
>> For additional commands, e-mail: struts-user-help@jakarta.apache.org
>>
>>
>>
>>
>
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: struts-user-unsubscribe@jakarta.apache.org
> For additional commands, e-mail: struts-user-help@jakarta.apache.org
>
>


---------------------------------------------------------------------
To unsubscribe, e-mail: struts-user-unsubscribe@jakarta.apache.org
For additional commands, e-mail: struts-user-help@jakarta.apache.org


Mime
View raw message