fix: address code review findings on virtual thread support

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/api/config/ConfigurationService.java

@@ -653,7 +653,7 @@ default InformerPool informerPool() {
    * the operator creates or updates.
    *
    * @return the list of aspects to apply to computed desired states, empty by default
-   * @since 5.6.0
+   * @since 5.7.0
    */
   default List<DesiredStateAspect> desiredStateAspects() {
     return List.of();

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/api/config/ConfigurationServiceOverrider.java

@@ -297,7 +297,7 @@ public ConfigurationServiceOverrider withInformerPool(InformerPool informerPool)
    *
    * @param desiredStateAspects the aspects to apply, in the order in which they should be applied
    * @return this {@link ConfigurationServiceOverrider} for chained customization
-   * @since 5.6.0
+   * @since 5.7.0
    */
   public ConfigurationServiceOverrider withDesiredStateAspects(
       List<DesiredStateAspect> desiredStateAspects) {
@@ -312,7 +312,7 @@ public ConfigurationServiceOverrider withDesiredStateAspects(
    *
    * @param desiredStateAspects the aspects to append, in the order in which they should be applied
    * @return this {@link ConfigurationServiceOverrider} for chained customization
-   * @since 5.6.0
+   * @since 5.7.0
    */
   public ConfigurationServiceOverrider addDesiredStateAspects(
       DesiredStateAspect... desiredStateAspects) {

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/BulkDependentResourceReconciler.java

@@ -117,9 +117,6 @@ public R update(R actual, R desired, P primary, Context<P> context) {
 
     @Override
     public Result<R> match(R resource, P primary, Context<P> context) {
-      // retrieve the desired state via the context so that it is processed the same way as for
-      // non-bulk dependents, in particular so that configured DesiredStateAspects are applied
-      // before matching
       return bulkDependentResource.match(resource, getOrComputeDesired(context), primary, context);
     }
 

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/event/source/informer/pool/AbstractInformerPool.java

@@ -117,7 +117,6 @@ protected SharedIndexInformer createInformer(InformerClassifier<?> classifier) {
     Optional.ofNullable(classifier.itemStore()).ifPresent(informer::itemStore);
 
     if (classifier.withoutNamespaceIndex()) {
-      // the framework only reads the indexes registered through the resource cache, never this one
       informer.removeNamespaceIndex();
     }
 

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/event/source/polling/PerResourcePollingEventSource.java

@@ -31,8 +31,6 @@
 
 import io.fabric8.kubernetes.api.model.HasMetadata;
 import io.javaoperatorsdk.operator.OperatorException;
-import io.javaoperatorsdk.operator.api.config.ConfigurationService;
-import io.javaoperatorsdk.operator.api.config.ExecutorServiceManager;
 import io.javaoperatorsdk.operator.api.reconciler.EventSourceContext;
 import io.javaoperatorsdk.operator.processing.event.ResourceID;
 import io.javaoperatorsdk.operator.processing.event.source.Cache;
@@ -80,25 +78,11 @@ public PerResourcePollingEventSource(
     this.resourceFetcher = config.resourceFetcher();
     this.registerPredicate = config.registerPredicate();
     this.configuredExecutorService = config.executorService();
-    var configurationService = configurationServiceOf(context);
-    this.useVirtualThreads =
-        configurationService != null && configurationService.useVirtualThreads();
+    this.useVirtualThreads = PollingExecutors.useVirtualThreads(context);
     this.ownsExecutorService = configuredExecutorService == null;
     this.period = config.defaultPollingPeriod();
   }
 
-  /**
-   * The configuration of the operator the event source belongs to, or {@code null} if it doesn't
-   * belong to one, which only happens when the event source is used standalone, outside an
-   * operator.
-   */
-  private static ConfigurationService configurationServiceOf(EventSourceContext<?> context) {
-    final var controllerConfiguration = context.getControllerConfiguration();
-    return controllerConfiguration == null
-        ? null
-        : controllerConfiguration.getConfigurationService();
-  }
-
   @Override
   public void start() throws OperatorException {
     if (isRunning()) {
@@ -119,8 +103,7 @@ private ScheduledExecutorService resolveExecutorService() {
     if (configuredExecutorService != null) {
       return configuredExecutorService;
     }
-    return ExecutorServiceManager.newScheduledExecutorService(
-        1, useVirtualThreads, "josdk-polling-" + name());
+    return PollingExecutors.newExecutor(name(), useVirtualThreads);
   }
 
   private Set<R> getAndCacheResource(P primary, boolean fromGetter) {

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/event/source/polling/PollingEventSource.java

@@ -30,7 +30,6 @@
 import io.fabric8.kubernetes.api.model.HasMetadata;
 import io.javaoperatorsdk.operator.OperatorException;
 import io.javaoperatorsdk.operator.api.config.ConfigurationService;
-import io.javaoperatorsdk.operator.api.config.ExecutorServiceManager;
 import io.javaoperatorsdk.operator.api.reconciler.EventSourceContext;
 import io.javaoperatorsdk.operator.health.Status;
 import io.javaoperatorsdk.operator.processing.event.ResourceID;
@@ -89,7 +88,7 @@ public class PollingEventSource<R, P extends HasMetadata, ID>
    */
   public PollingEventSource(
       Class<R> resourceClass, EventSourceContext<P> context, PollingConfiguration<R, ID> config) {
-    this(resourceClass, config, configurationServiceOf(context));
+    this(resourceClass, config, PollingExecutors.useVirtualThreads(context));
   }
 
   /**
@@ -100,34 +99,19 @@ public PollingEventSource(
    */
   @Deprecated(since = "5.7.0")
   public PollingEventSource(Class<R> resourceClass, PollingConfiguration<R, ID> config) {
-    this(resourceClass, config, null);
+    this(resourceClass, config, false);
   }
 
   private PollingEventSource(
-      Class<R> resourceClass,
-      PollingConfiguration<R, ID> config,
-      ConfigurationService configurationService) {
+      Class<R> resourceClass, PollingConfiguration<R, ID> config, boolean useVirtualThreads) {
     super(config.name(), resourceClass, config.resourceIDMapper());
     this.genericResourceFetcher = config.genericResourceFetcher();
     this.period = config.period();
     this.configuredExecutorService = config.executorService();
-    this.useVirtualThreads =
-        configurationService != null && configurationService.useVirtualThreads();
+    this.useVirtualThreads = useVirtualThreads;
     this.ownsExecutorService = configuredExecutorService == null;
   }
 
-  /**
-   * The configuration of the operator the event source belongs to, or {@code null} if it doesn't
-   * belong to one, which only happens when the event source is used standalone, outside an
-   * operator.
-   */
-  private static ConfigurationService configurationServiceOf(EventSourceContext<?> context) {
-    final var controllerConfiguration = context.getControllerConfiguration();
-    return controllerConfiguration == null
-        ? null
-        : controllerConfiguration.getConfigurationService();
-  }
-
   @Override
   public void start() throws OperatorException {
     if (pollingTask != null) {
@@ -187,8 +171,7 @@ private ScheduledExecutorService resolveExecutorService() {
     if (configuredExecutorService != null) {
       return configuredExecutorService;
     }
-    return ExecutorServiceManager.newScheduledExecutorService(
-        1, useVirtualThreads, "josdk-polling-" + name());
+    return PollingExecutors.newExecutor(name(), useVirtualThreads);
   }
 
   protected synchronized void getStateAndFillCache() {
@@ -204,7 +187,6 @@ public interface GenericResourceFetcher<R> {
   public void stop() throws OperatorException {
     super.stop();
     if (pollingTask != null) {
-      // as with the java.util.Timer this replaces, an ongoing poll is left to finish
       pollingTask.cancel(false);
       pollingTask = null;
     }

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/event/source/polling/PollingExecutors.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright Java Operator SDK Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.javaoperatorsdk.operator.processing.event.source.polling;
+
+import java.util.concurrent.ScheduledExecutorService;
+
+import io.javaoperatorsdk.operator.api.config.ExecutorServiceManager;
+import io.javaoperatorsdk.operator.api.reconciler.EventSourceContext;
+
+final class PollingExecutors {
+
+  private PollingExecutors() {}
+
+  /**
+   * Whether the operator the event source belongs to is configured to use virtual threads. The
+   * controller configuration is {@code null} when the event source is used standalone, outside an
+   * operator.
+   */
+  static boolean useVirtualThreads(EventSourceContext<?> context) {
+    final var controllerConfiguration = context.getControllerConfiguration();
+    if (controllerConfiguration == null) {
+      return false;
+    }
+    final var configurationService = controllerConfiguration.getConfigurationService();
+    return configurationService != null && configurationService.useVirtualThreads();
+  }
+
+  static ScheduledExecutorService newExecutor(String eventSourceName, boolean useVirtualThreads) {
+    return ExecutorServiceManager.newScheduledExecutorService(
+        1, useVirtualThreads, "josdk-polling-" + eventSourceName);
+  }
+}

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/event/source/timer/TimerEventSource.java

@@ -54,6 +54,11 @@ public TimerEventSource() {
     this.ownsExecutorService = true;
   }
 
+  /**
+   * @deprecated use {@link #TimerEventSource(String, boolean, Supplier)} instead, passing {@code
+   *     null} as the supplier to keep the previous behavior.
+   */
+  @Deprecated(since = "5.7.0")
   public TimerEventSource(String name, boolean triggerReconcilerOnAllEvents) {
     this(name, triggerReconcilerOnAllEvents, null);
   }
@@ -134,8 +139,6 @@ public void onResourceDeleted(R resource) {
   public void cancelOnceSchedule(ResourceID customResourceUid) {
     var scheduled = onceTasks.remove(customResourceUid);
     if (scheduled != null) {
-      // as with the java.util.TimerTask this replaces, a task that is already running is left to
-      // finish
       scheduled.cancel(false);
     }
   }