OpenTelemetry - java

API

Context

• Apply limits to baggage entries for W3CBaggagePropagator, OtTracePropagator, JaegerPropagator (#8378)

SDK

Traces

• Avoid parentContext allocation on span start for the common case (#8332)

Metrics

• Add setMaxExportBatchSize to PeriodicMetricReaderBuilder (#8296)
• Fix PeriodicMetricReader shutdown race that could drop the final flush (#8299)

Exporters

• BREAKING Prometheus: Change default server host from 0.0.0.0 to localhost (#8298)
• BREAKING Prometheus: Stop converting unit "1" to "ratio" (#8252)
• OTLP: Fix null input handling in StringEncoder (#8312)
• OTLP: Align proto field types and wire tag names in marshalers (#8293)
• OTLP: Fix MarshalerUtil sizeRepeatedString calculation (#8284)
• OTLP: Bound JdkHttpSender thread pool size to prevent unbounded thread creation (#8276)
• OTLP Profiles: Split profiles data model into separate sdk-profiles and JFR shim modules (#8207)
• OTLP Profiles: Publish alpha release of opentelemetry-sdk-profiles and opentelemetry-exporter-otlp-profiles (#8351)

Extensions

• BREAKING Declarative config: Extract to new opentelemetry-sdk-extension-declarative-config artifact with new package io.opentelemetry.sdk.autoconfigure.declarativeconfig (#8265)
• Autoconfigure: Add file size validation in OtlpConfigUtil to avoid unsafe cast to int (#8287)
• Declarative config: Fix collection fields to not be initialized to empty by default (#8356)
• Incubator: Add EventToSpanEventBridge to bridge log-based events to span events (#8372)

Testing

• Add @Nullable to equalTo value argument in OpenTelemetryAssertions (#8301)
• Add hasValueSatisfying to LongPointAssert and DoublePointAssert for fuzzy value matching (#8328)
• Add containsPointsSatisfying to metric data asserts for "each given assertion must be satisfied by at least one point, extras allowed" checks on sum, gauge, histogram, exponential histogram, and summary data (#8329)

Project tooling

• Add initial OSGi support (#7964)
• Promote ApiUsageLogger to opentelemetry-common public API (#8318)
• Establish exception logging guidelines and fix inconsistent patterns across exporters and SDK (#8231)
• Add *.impl.* package naming convention for internal code with japicmp compatibility (#8325)
• Add Sonatype dependency audit to build (#8365)

🙇 Thank you

This release was possible thanks to the following contributors who shared their brilliant ideas and awesome pull requests:

@abdessattar23 @anuq @breedx-splk @cijothomas @dashpole @jack-berg @jaydeluca @jhalliday @jkwatson @jsuereth @laeubi @laurit @maxiking203 @opentelemetrybot @psx95 @robsunday @royteeuwen @Sandared @stbischof @SylvainJuge @trask @utafrali @VamshikrishnaMonagari @zeitlinger