[jax-rs-spec users] [jsr339-experts] Re: Binding of ContainerRequestContext to Servlet

From: Bill Burke <>
Date: Fri, 07 Sep 2012 09:22:07 -0400

On 9/7/2012 7:53 AM, Markus KARG wrote:
>> -----Original Message-----
>> From: Sergey Beryozkin []
>> Sent: Freitag, 7. September 2012 11:37
>> To:
>> Subject: [jsr339-experts] Binding of ContainerRequestContext to Servlet
>> The documentation for all the ContainerRequestContext methods to do
>> with retrieving or setting the properties refers to Servlet
>> (effectively
>> HttpServletRequest) attributes.
>> getPropertyNames() even returns Enumeration.
>> This concerns me a bit. I think if some users are keen to work with
>> Servlet API in context of JAX-RS then they will expect more than just
>> the ability to get an access to the underlying Servlet attributes. In
>> other words, they'd want HTTPServletRequest.
>> AFAIK, the whole idea was to be able to exchange properties between the
>> filters, as such I do not see why Servlet even has to be mentioned, and
>> the ancient legacy Enumeration interface has to be introduced into the
>> signature.
>> It also may send a message that JAX-RS is some kind of thin wrapper on
>> top of Servlet API.
>> Thoughts ?
>> Cheers, Sergey
> I also think that the JAX-RS API should not be too Servlet API related. If a
> container is not using Servlet at all (what might become more and more
> essential in future, when platforms turn from Web Hosting Cluster to
> Application Clouds), there should be no need for the implementor to provide
> a Servlet API class. This has some kind of design smell ("We all base on
> Servlet API, so let's assume this for all others").

I think you're misunderstanding things. There is no requirement on the
Servlet API, just that Filter/Interceptor properties are backed by
HttpServletRequest in a servlet environment. This makes JAX-RS more
seemless integratable.

Maybe a changing of the wording is:

Properties should be backed by any underyling mechanism to associate
properties with the http request. So, a JAX-RS container written on top
of the Servlet API should have properties backed by HttpServletRequest
attributes. This allows JAX-Rs filters and interceptors to seemlessly
pass information between JAX-RS and their underlying http implementations.

That clear things up?

FYI, similarly, I'm pushing for to be backed by
ServletContext init/context params so you can easily pass config from
web.xml into your components.

Bill Burke
JBoss, a division of Red Hat