Re: Novice Tomcat design pattern question

From:

=?ISO-8859-1?Q?Arne_Vajh=F8j?= <arne@vajhoej.dk>

Newsgroups:

comp.lang.java.programmer

Date:

Sun, 02 Dec 2007 19:18:14 -0500

Message-ID:

<47534b42$0$90275$14726298@news.sunsite.dk>

Owen Jacobson wrote:

On 2007-12-02 14:20:53 -0800, TwelveEighty <twelve.eighty@gmail.com> said:

On Dec 2, 12:42 pm, Juha Laiho <Juha.La...@iki.fi> wrote:

Another way to achieve the same would be to write and declare
a ServletContextListener to handle the startup. This would have
the added benefit of also being able to shut down the "external"
server cleanly when Tomcat is being shut down.

After Arne's post, I started looking into this and I noticed that
there is also an init() and destroy() method on the HttpServlet
itself. What would be a better approach, to use the
ServletContextListener, or use the init() and destroy() methods for
startup and shutdown of the "external" server?

A ServletContextListener doesn't have to have any code in it to handle
(or at least actively reject) servlet API calls

Neither does a startup servlet. It inherits a couple of do nothing
methods.

and has much simpler
instantiation guarantees ("once", as opposed to "once, unless you
implement specific marker interfaces or the configuration says
otherwise").

Not doing anything special giving the desired effect is not that bad.

Arne