[jax-rs-spec users] [jsr339-experts] Re: Re: Re: Back To DI in Subresources

From: Santiago Pericas-Geertsen <>
Date: Fri, 20 Apr 2012 11:05:04 -0400

On Apr 19, 2012, at 5:01 AM, Sergey Beryozkin wrote:

>> Why not both? As you say, (1) is more flexible but (2) is quite convenient.
> I don't understand how the sub-resource injection can work at all.
> Lets take an example where a root resource is a singleton.
> This root resource can return sub-resource instances. Such instances can be created at a per-request basis or may've been pre-allocated and are singletons too. Only the root resource knows the rules.
> How can the runtime make sure that the injection into sub-resources is thread-safe ?

 The spec already states that field/property injection is only guaranteed to work in the default per-request lifecycle, given that it is only lifecycle mandated by the spec.

 Back to your point, are you suggesting that the problem is significantly different from injecting into a field/property in singleton _root_ resource class? You must have concurrency issues there too.

-- Santiago