Add AlwaysRecordSampler

[majanjua-amzn]

Background

Spec issue: open-telemetry/opentelemetry-specification#4698
Spec PR: open-telemetry/opentelemetry-specification#4699

Adding built in access to the RECORD_ONLY flag for sampling to allow for users to process spans without exporting them.

Changes

• Add AlwaysRecordSampler as per spec, following aws-otel-java-instrumentation implementation
• Add unit tests

Testing

Added unit tests, ./gradlew spotlessApply && ./gradlew build && ./gradlew check as per CONTRIBUTING.md guide

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.15%. Comparing base (18f8a13) to head (f699191).
⚠️ Report is 6 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #7877   +/-   ##
=========================================
  Coverage     90.15%   90.15%           
- Complexity     7476     7481    +5     
=========================================
  Files           836      837    +1     
  Lines         22551    22567   +16     
  Branches       2224     2225    +1     
=========================================
+ Hits          20330    20346   +16     
  Misses         1517     1517           
  Partials        704      704           

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[majanjua-amzn]

Ready for review!

[breedx-splk]

Thanks for the PR. I think my biggest question is about how this will get used (if internal), but otherwise is looking good to me. There's also a merge conflict that needs to be resolved before merge.

[breedx-splk]

Is this the correct package? How are you planning for this to be consumed by users if it's internal?

[jack-berg]

Experimental SDK components is the place we've been least consistent about in terms of packaging, since sometimes the concept needs to be bundled into the SDK internals to work (i.e. ExceptionAttributeResolver). But for components which are SDK extension plugin interfaces (span processor, sampler, etc), we've been keeping them in opentelemetry-sdk-extension-incubator. Here's the relevant package for samplers: https://github.com/open-telemetry/opentelemetry-java/tree/main/sdk-extensions/incubator/src/main/java/io/opentelemetry/sdk/extension/incubator/trace/samplers

[majanjua-amzn]

Moved the code to the incubator package

[jack-berg]

Couple small things that need adjusting. Thanks for working on this!

[breedx-splk]

bump @majanjua-amzn in case you can circle back to this now in the new year. 😉 Thanks again!

[majanjua-amzn]

Ready for review again! Apologies for the delay, cc @jack-berg since you marked it as requested change, thanks in advance

[jack-berg]

Thanks!

[otelbot]

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