Good day.
I have a lot of pleasant experience writing Jersey based web services
that do not also use Spring DI.
The way I traditionally made things like ServletContext and
HttpServletRequest available to my resource classes was to define an
abstract resource base class whose ctor took this objects as
arguments. For example, here is such a base class ctor:
protected AbstractResource(@Context ServletContext servletContext,
@Context HttpServletRequest httpServletRequest, @Context UriInfo
uriInfo) {
...
}
Classes that extend this AbstractResource can then use the
servletContext, e.g., in whatever way they see fit.
However, I have recently inherited Jersey web service code that uses
Spring DI, more specifically, resource classes marked with @Component
with the Spring default Singleton scope.
My question is this: What is the best practice for acquiring
request-based references to things like the ServletContext (not
request-based, but no matter) and HttpServletRequest in this new
regime of Spring managed resource class lifecycle?
I have seen examples whereby, e.g., the HttpServletRequest is acquired
via an "@Context HttpServletRequest request" argument to the resource
class method handling a specific request. However, I'm not thrilled
with this, as every method that needs these @Context references must
include them in their method signature, which is an almost immediate
violation of the DRY principle.
I have also seen mentioned a configuration of the Spring container
whereby Singleton beans can be produced that contain beans with
per-request lifecycles. Frankly, I'm not thrilled with this, either,
as in many months down the road, I may forget how this actually works,
and will have to relearn how and why it works.
Would someone be kind enough to talk about how they've handled this.
I may not have the freedom to change the lifecycle of the resources
classes from Singleton to request-scope ("prototype", I believe).
Even if I do, I still want to understand what best practice surround
this issue for the case of Singleton resource classes handling
per-request underlying servlet objects.
Thank you very kindly.
Mark
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Mark