Samplers use Locale dependent formatting for description

[lmonkiewicz]

Describe the bug
RateLimiingSampler and TraceIdRationBasedSampler use String.format("RateLimitingSampler{%.2f}", maxTracesPerSecond) for building a description. Formatting of numbers in such way may result in 999.00 for en_US locale and 999,00 for pl_PL.

I propose to enforce locale for those two samplers, using String.format(Locale.ENGLISH, "RateLimitingSampler{%.2f}", maxTracesPerSecond).

If that solution is acceptable, I can take care of it.

Steps to reproduce
Change locale on your JVM to pl_PL and run JaegerRemoteSamplerTest test suite. Most tests will fail on checking of description formats.

What did you expect to see?
Behavior independent of locale.

What did you see instead?

Expecting actual:
  "JaegerRemoteSampler{ParentBased{root:RateLimitingSampler{999,00},remoteParentSampled:AlwaysOnSampler,remoteParentNotSampled:AlwaysOffSampler,localParentSampled:AlwaysOnSampler,localParentNotSampled:AlwaysOffSampler}}"
to contain:
  "RateLimitingSampler{999.00}" 

What version and what artifacts are you using?
Artifacts: opentelemetry-java, jaeger-remote-sampler
Version: fdfacb0bdea770f354e27305b5aab77a9d965a4f

Environment
Compiler: OpenJDK 18.0.1
OS: MacOS

[jack-berg]

Not saying I disagree with a standard locale, but curious how this impacted you in practice?

[lmonkiewicz]

Not saying I disagree with a standard locale, but curious how this impacted you in practice?

Not a real usage case, but when I was working on another issue, Jaeger tests were failing all the time. Took me a while before I noticed why.

[jack-berg]

Ah I missed that JaegerRemoteSamplerTest asserts on the locale specific string! Seems reasonable to make the formatting consistent. How about using something like new DecimalFormat("#.#######").format(..) rather than tying the code to a specific locale?

[lmonkiewicz]

Ah I missed that JaegerRemoteSamplerTest asserts on the locale specific string! Seems reasonable to make the formatting consistent. How about using something like new DecimalFormat("#.#######").format(..) rather than tying the code to a specific locale?

Fine by me, you can assign it to me.