Add Javadoc

pulsar-opentelemetry/src/main/java/org/apache/pulsar/opentelemetry/OpenTelemetryAttributes.java

@@ -20,6 +20,13 @@
 
 import io.opentelemetry.api.common.AttributeKey;
 
+/**
+ * Common OpenTelemetry attributes to be used by Pulsar components.
+ */
 public interface OpenTelemetryAttributes {
+    /**
+     * The name of the Pulsar cluster. This attribute is automatically added to all signals by
+     * {@link OpenTelemetryService}.
+     */
     AttributeKey<String> PULSAR_CLUSTER = AttributeKey.stringKey("pulsar.cluster");
 }

pulsar-opentelemetry/src/main/java/org/apache/pulsar/opentelemetry/OpenTelemetryService.java

@@ -44,11 +44,23 @@ public class OpenTelemetryService implements Closeable {
 
     private final OpenTelemetrySdk openTelemetrySdk;
 
+    /**
+     * Instantiates the OpenTelemetry SDK. All attributes are overridden by system properties or environment
+     * variables.
+     *
+     * @param clusterName
+     *      The name of the Pulsar cluster. Cannot be null or blank.
+     * @param serviceName
+     *      The name of the service. Optional.
+     * @param serviceVersion
+     *      The version of the service. Optional.
+     * @param sdkBuilderConsumer
+     *      Allows customizing the SDK builder; for testing purposes only.
+     */
     @Builder
     public OpenTelemetryService(String clusterName,
                                 String serviceName,
                                 String serviceVersion,
-                                // Allows customizing the SDK builder; for testing purposes only.
                                 @VisibleForTesting Consumer<AutoConfiguredOpenTelemetrySdkBuilder> sdkBuilderConsumer) {
         checkArgument(StringUtils.isNotBlank(clusterName), "Cluster name cannot be empty");
         var sdkBuilder = AutoConfiguredOpenTelemetrySdk.builder();

pulsar-opentelemetry/src/main/java/org/apache/pulsar/opentelemetry/package-info.java

@@ -16,4 +16,9 @@
  * specific language governing permissions and limitations
  * under the License.
  */
+
+/**
+ * Provides a wrapper layer for the OpenTelemetry API to be used in Pulsar.
+ * @since 3.3.0
+ */
 package org.apache.pulsar.opentelemetry;