opentelemetry-java v1.66.0

API

• Fix Baggage.fromContext() and Baggage.fromContextOrNull() to handle a null context (#8667)
• Do not percent-encode W3C baggage metadata (#8682)
• Fix ArrayIndexOutOfBoundsException in OtelEncodingUtils for invalid hex characters (#8748)

SDK

Traces

• Record processed spans before export completes and reject new spans on shutdown in SpanProcessor self-observability instrumentation (#8735)

Metrics

• Improve explicit bucket histogram contention performance (#8717)

Logs

• Record processed logs before export completes and reject new logs on shutdown in LogRecordProcessor self-observability instrumentation (#8698)

Exporters

• OTLP: Respect Retry-After in OTLP HTTP senders (#8633)
• OTLP: Add setEnabledProtocols option to OTLP HTTP exporter builders (#8610)
• OTLP: Reject mixing keyManager and sslContext in TlsConfigHelper (#8710)
• OTLP: Fix OkHttpGrpcSender mTLS when using the platform default trust store (#8758)
• OTLP: Suppress instrumentation of exporter requests in JdkHttpSender (#8757)
• OTLP: Accept RFC 1123 hostnames in EndpointUtil.validateEndpoint for OkHttp senders (#8746)
• OTLP: Include the number of affected items in exporter error logging (#8780)
• OTLP: Add toString to OtlpJsonLogging{Span,Metric,LogRecord}Exporter (#8725)
• OTLP Profiles: Improve JFR export example and align LinkData null-element handling with the spec (#8349)
• Prometheus: Remove default host log warning in PrometheusHttpServerBuilder (#8679)
• Prometheus: Align UCUM byte unit conversions with the specification table (#8752)

Extensions

• BREAKING Declarative config: Rename generated model POJO setters from with<Prop> to set<Prop> (#8742)
• Declarative config: Resolve experimental properties on stable APIs in generated model POJOs (#8654)
• Declarative config: Fix inverted scope_info_enabled and target_info_enabled flags in the Prometheus component provider (#8750)
• Declarative config: Support output_stream in otlp_file/development (#8676)
• Incubator: Add toString to ComposableAnnotatingSampler (#8645)

Project tooling

• Remediate zizmor findings in GitHub Actions workflows (#8592)

🙇 Thank you

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

@abdessattar23 @adhamahmad @ADITYA-CODE-SOURCE @anoopjb @anuraaga @arimu1 @basti1302 @bogdandrutu @breedx-splk @cdsap @chatgpt-codex-connector @gniadeck @itsmehotpants @ivamly @jack-berg @jameyg42 @jaydeluca @jhalliday @jkwatson @kalayciburak @LarryHu0217 @LikeTheSalad @maryliag @NithinU2802 @noor-ahmadi @opentelemetry-pr-dashboard @opentelemetrybot @psx95 @Rajkaran-122 @rmannibucau @robintra @thswlsqls @trask @zeitlinger

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Source open-telemetry/opentelemetry-java · v1.66.0 · 2026-09-11 · upstream release

Mirrored verbatim for indexing. All rights belong to the upstream project.