Prepare for 1.38.0 release (#6441)

Co-authored-by: Trask Stalnaker <trask.stalnaker@gmail.com>

CHANGELOG.md

@@ -2,6 +2,89 @@
 
 ## Unreleased
 
+### API
+
+* Stabilize synchronous gauge
+  ([#6419](https://github.com/open-telemetry/opentelemetry-java/pull/6419))
+
+#### Incubator
+
+* Add put(AttributeKey<T>, T) overload to EventBuilder
+  ([#6331](https://github.com/open-telemetry/opentelemetry-java/pull/6331))
+
+#### Baggage
+
+* Baggage filters space-only keys
+  ([#6431](https://github.com/open-telemetry/opentelemetry-java/pull/6431))
+
+### SDK
+
+* Add experimental scope config to enable / disable scopes (i.e. meter, logger, tracer)
+  ([#6375](https://github.com/open-telemetry/opentelemetry-java/pull/6375))
+
+#### Traces
+
+* Add ReadableSpan#getAttributes
+  ([#6382](https://github.com/open-telemetry/opentelemetry-java/pull/6382))
+* Use standard ArrayList size rather than max number of links for initial span links allocation
+  ([#6252](https://github.com/open-telemetry/opentelemetry-java/pull/6252))
+
+#### Metrics
+
+* Use low precision Clock#now when computing timestamp for exemplars
+  ([#6417](https://github.com/open-telemetry/opentelemetry-java/pull/6417))
+* Update invalid instrument name log message now that forward slash `/` is valid
+  ([#6343](https://github.com/open-telemetry/opentelemetry-java/pull/6343))
+
+#### Exporters
+
+* Introduce low allocation OTLP marshalers. If using autoconfigure, opt in
+  via `OTEL_JAVA_EXPERIMENTAL_EXPORTER_MEMORY_MODE=REUSABLE_DATA`.
+  * Low allocation OTLP logs marshaler
+    ([#6429](https://github.com/open-telemetry/opentelemetry-java/pull/6429))
+  * Low allocation OTLP metrics marshaler
+    ([#6422](https://github.com/open-telemetry/opentelemetry-java/pull/6422))
+  * Low allocation OTLP trace marshaler
+    ([#6410](https://github.com/open-telemetry/opentelemetry-java/pull/6410))
+  * Add memory mode support to OTLP exporters
+    ([#6430](https://github.com/open-telemetry/opentelemetry-java/pull/6430))
+  * Marshal span status description without allocation
+    ([#6423](https://github.com/open-telemetry/opentelemetry-java/pull/6423))
+  * Add private constructors for stateless marshalers
+    ([#6434](https://github.com/open-telemetry/opentelemetry-java/pull/6434))
+* Mark opentelemetry-exporter-sender-jdk stable
+  ([#6357](https://github.com/open-telemetry/opentelemetry-java/pull/6357))
+* PrometheusHttpServer prevent concurrent reads when reusable memory mode
+  ([#6371](https://github.com/open-telemetry/opentelemetry-java/pull/6371))
+* Ignore TLS components (SSLContext, TrustManager, KeyManager) if plain HTTP protocol is used for
+  exporting
+  ([#6329](https://github.com/open-telemetry/opentelemetry-java/pull/6329))
+* Add is_remote_parent span flags to OTLP exported Spans and SpanLinks
+  ([#6388](https://github.com/open-telemetry/opentelemetry-java/pull/6388))
+* Add missing fields to OTLP metric exporters `toString()`
+  ([#6402](https://github.com/open-telemetry/opentelemetry-java/pull/6402))
+
+#### Extensions
+
+* Rename otel.config.file to otel.experimental.config.file for autoconfigure
+  ([#6396](https://github.com/open-telemetry/opentelemetry-java/pull/6396))
+
+### OpenCensus Shim
+
+* Fix opencensus shim spanBuilderWithRemoteParent behavior
+  ([#6415](https://github.com/open-telemetry/opentelemetry-java/pull/6415))
+
+### Tooling
+
+* Add additional API incubator docs
+  ([#6356](https://github.com/open-telemetry/opentelemetry-java/pull/6356))
+* Run build on java 21
+  ([#6370](https://github.com/open-telemetry/opentelemetry-java/pull/6370))
+* Fix running tests with java 8 on macos
+  ([#6411](https://github.com/open-telemetry/opentelemetry-java/pull/6411))
+* Move away from deprecated gradle enterprise APIs
+  ([#6363](https://github.com/open-telemetry/opentelemetry-java/pull/6363))
+
 ## Version 1.37.0 (2024-04-05)
 
 **NOTICE:** This release contains a significant restructuring of the experimental event API and the API incubator artifact. Please read the notes in the `API -> Incubator` section carefully.

api/all/src/main/java/io/opentelemetry/api/metrics/DoubleGauge.java

@@ -9,7 +9,11 @@
 import io.opentelemetry.context.Context;
 import javax.annotation.concurrent.ThreadSafe;
 
-/** A gauge instrument that synchronously records {@code double} values. */
+/**
+ * A gauge instrument that synchronously records {@code double} values.
+ *
+ * @since 1.38.0
+ */
 @ThreadSafe
 public interface DoubleGauge {
   /**

api/all/src/main/java/io/opentelemetry/api/metrics/DoubleGaugeBuilder.java

@@ -77,6 +77,7 @@ default ObservableDoubleMeasurement buildObserver() {
    * the value of the last recorded measurement is exported.
    *
    * @return The DoubleGauge instrument.
+   * @since 1.38.0
    */
   default DoubleGauge build() {
     return DefaultMeter.getInstance().gaugeBuilder("noop").build();

api/all/src/main/java/io/opentelemetry/api/metrics/LongGauge.java

@@ -9,7 +9,11 @@
 import io.opentelemetry.context.Context;
 import javax.annotation.concurrent.ThreadSafe;
 
-/** A gauge instrument that synchronously records {@code long} values. */
+/**
+ * A gauge instrument that synchronously records {@code long} values.
+ *
+ * @since 1.38.0
+ */
 @ThreadSafe
 public interface LongGauge {
   /**

api/all/src/main/java/io/opentelemetry/api/metrics/LongGaugeBuilder.java

@@ -74,6 +74,7 @@ default ObservableLongMeasurement buildObserver() {
    * the value of the last recorded measurement is exported.
    *
    * @return The LongGauge instrument.
+   * @since 1.38.0
    */
   default LongGauge build() {
     return DefaultMeter.getInstance().gaugeBuilder("noop").ofLongs().build();

sdk/common/src/main/java/io/opentelemetry/sdk/common/Clock.java

@@ -50,6 +50,8 @@ static Clock getDefault() {
    * ns precision is possible in java 8, regardless of the value of {@code highPrecision}.
    *
    * <p>See {@link #now()} javadoc for details on usage.
+   *
+   * @since 1.38.0
    */
   default long now(boolean highPrecision) {
     return now();

sdk/metrics/src/main/java/io/opentelemetry/sdk/metrics/InstrumentType.java

@@ -10,12 +10,16 @@
  *
  * @since 1.14.0
  */
+@SuppressWarnings({"MissingSummary", "SummaryJavadoc"})
 public enum InstrumentType {
   COUNTER,
   UP_DOWN_COUNTER,
   HISTOGRAM,
   OBSERVABLE_COUNTER,
   OBSERVABLE_UP_DOWN_COUNTER,
   OBSERVABLE_GAUGE,
+  /**
+   * @since 1.38.0
+   */
   GAUGE,
 }

sdk/metrics/src/main/java/io/opentelemetry/sdk/metrics/export/AggregationTemporalitySelector.java

@@ -81,6 +81,8 @@ static AggregationTemporalitySelector lowMemory() {
   /**
    * Returns a string representation of this selector, for using in {@link Object#toString()}
    * implementations.
+   *
+   * @since 1.38.0
    */
   static String asString(AggregationTemporalitySelector selector) {
     StringJoiner joiner = new StringJoiner(", ", "AggregationTemporalitySelector{", "}");

sdk/metrics/src/main/java/io/opentelemetry/sdk/metrics/export/DefaultAggregationSelector.java

@@ -64,6 +64,8 @@ default DefaultAggregationSelector with(InstrumentType instrumentType, Aggregati
   /**
    * Returns a string representation of this selector, for using in {@link Object#toString()}
    * implementations.
+   *
+   * @since 1.38.0
    */
   static String asString(DefaultAggregationSelector selector) {
     StringJoiner joiner = new StringJoiner(", ", "DefaultAggregationSelector{", "}");

sdk/trace/src/main/java/io/opentelemetry/sdk/trace/ReadableSpan.java

@@ -124,6 +124,7 @@ default InstrumentationScopeInfo getInstrumentationScopeInfo() {
    * #getAttribute(AttributeKey)}.
    *
    * @return the Span attributes, or {@link Attributes#empty()} if the span has no attributes.
+   * @since 1.38.0
    */
   default Attributes getAttributes() {
     return Attributes.empty();