Version 1.4.0

API

Enhancements

• You can now assign an OpenTelemetry schema URL to a Tracer via the new TracerBuilder class that is
  accessed via the TracerProvider or any of the global instances that delegate to one.

Extensions

• A new @SpanAttribute annotation has been added for adding method parameters to spans automatically. This
  has no implementation in this release, but should be supported by the auto-instrumentation agent soon.

Exporters

Bugfixes

• Calling shutdown() multiple times on the OTLP and Jaeger GRPC-based exporters will now work correctly and return a proper
  implementation of CompletableResultCode for the calls beyond the first.

SDK

Bugfixes

• If the jdk.unsupported package is not available, the BatchSpanProcessor will now fall back to a supported, standard Queue implementation.

Enhancements

• A Resource can now be assigned an OpenTelemetry schema URL via the ResourceBuilder or the create(Attributes, String)
  method on the Resource itself.
• You can now obtain a default Clock based on system time via Clock.getDefault. The sdk-testing artifact also provides
  a TestClock for unit testing.

Semantic Conventions (alpha)

• The SemanticAttributes and ResourceAttributes classes have been updated to match the semantic conventions
  as of specification release 1.4.0. These classes also now expose a SCHEMA_URL field which points at the
  version of the OpenTelemetry schema the files were generated from. There are no breaking changes in this update, only additions.

Metrics (alpha)

• You can now assign an OpenTelemetry schema URL to a Meter via the new MeterBuilder class that is
  accessed via the MeterProvider or any global instances that delegate to one.
• The metrics SDK now utilizes Attributes rather than Labels internally.
• You can now register an IntervalMetricReader as global and forceFlush the global reader.