On Apr 8, 2008, at 7:54 AM, Reinhard Poetz wrote:
At the ApacheCon Carsten, Grek and I had the chance to talk about
the JNet
integration and to find a solution that (hopefully) works.
* First we all believe that it is not a good idea to consider the
blockcontext:/
URLs as expressions that are resolved to file: URLs. We want to
make them
real URLs.
* Taking care of URL handling is NOT the responsiblity the Servlet-
Service
framework.
* The installation of blocks (= extracting to the working directory
of the web
application) is NOT the responsibility of the Spring configurator.
* The installation of blocks shouldn't be done by using Spring so
that the list
of all installed blocks is generally available.
So what do we propose?
----------------------
* Get rid of the SourceResolver usage in the SSF implementation code.
* Do the installation of blocks in a ServletContextListener. The map
of all
installed blocks can be stored as a servlet context attribute then
and
being looked up from there easily.
* Provide a Spring aspect that intercepts all service() method calls
using
an around advice and installs a URLStreamHandlerFactory (-> that's
the piece
of code responsible for returning the correct StreamHandler for a
particular
protocol). The list of available StreamHanlders can be gathered by
using
a BeanMap that collects all beans of a particular type.
Doing it this way ensures that the installation and uninstallation of
URLStreamHandlerFactories is done per thread and we are on the safe
side
when there is more than one web application running the same JVM.
As a first step we want to make these changes happen without
creating any
additional modules. But when things become more stable
(implementation-wise) we
will propose to create a separate module for the "BlockInstaller"
and find the final home for "JNet".
Sounds good to me.
Vadim
