Introduce system property for controlling URI validation

[geoand]

This is not meant to be used in production and is mainly
aimed at benchmarking.
The property is very much analogous to what Vert.x provides
with vertx.disableHttpHeadersValidation

cc @Sanne @johnaohara

[Sanne]

Interesting :)
Might be relevant for some work @franz1981 is doing today

[franz1981]

must be static too in order to be treated as constant

[gastaldi]

👍🏻 Good catch!

[geoand]

I thought of that, but decided against it so as to not have it captured during native image build.

C2 will make it a constant in any case no?

I'm likely being too paranoid about the native build thing, it's very unlikely someone would set this at build time (as it's undocumented)

[franz1981]

Makes sense, but still the comment

this is a constant so the JIT can eliminate validation code and save some allocations.

is not valid anymore
Netty is using many system properties like these and I expect them to be correctly handled on native image (which knowledge I'm still lacking) - is it not the same? (newbie question :) )

[geoand]

The constants we care about to not be captured in native image, we explicitly "reset" using a substitution.

We could of course do that here too, but it feels like too much work for such a niche feature

[franz1981]

At this point let's treat this as a (non-JIT) final field that save some useless work (that's fine) - but at least I suggest to read it somewhere (a static somewhere) in order to save the sys prop to be read each time (unless we care about it changing over time) for each instance creation

[geoand]

Good point, however the handler is only created once :).

I did push an update to the comment