Added an explicit way to set ExecuteExistingDelayedTasksAfterShutdown…

… property.

This closes an existing issue:
spring-projects#26719

gradle.properties

@@ -1,5 +1,5 @@
 version=5.3.7-SNAPSHOT
-org.gradle.jvmargs=-Xmx1536M
+#org.gradle.jvmargs=-Xmx1536M
 org.gradle.caching=true
 org.gradle.parallel=true
 kotlin.stdlib.default.dependency=false

spring-context/src/main/java/org/springframework/scheduling/concurrent/ThreadPoolTaskScheduler.java

@@ -64,6 +64,8 @@ public class ThreadPoolTaskScheduler extends ExecutorConfigurationSupport
 
 	private volatile boolean removeOnCancelPolicy;
 
+	private volatile boolean executeExistingDelayedTasksAfterShutdownPolicy;
+
 	@Nullable
 	private volatile ErrorHandler errorHandler;
 
@@ -106,6 +108,23 @@ else if (removeOnCancelPolicy && this.scheduledExecutor != null) {
 		}
 	}
 
+	/**
+	 * Set the execute-existing-delayed-tasks-after-shutdown mode on {@link ScheduledThreadPoolExecutor}.
+	 * <p>Default is {@code true}. If set to {@code false}, the target executor will be
+	 * switched into execute-existing-delayed-tasks-after-shutdown.
+	 * <p><b>This setting can be modified at runtime, for example through JMX.</b>
+	 */
+	public void setExecuteExistingDelayedTasksAfterShutdownPolicy(boolean executeExistingDelayedTasksAfterShutdownPolicy) {
+		this.executeExistingDelayedTasksAfterShutdownPolicy = executeExistingDelayedTasksAfterShutdownPolicy;
+		if (this.scheduledExecutor instanceof ScheduledThreadPoolExecutor) {
+			((ScheduledThreadPoolExecutor) this.scheduledExecutor)
+					.setExecuteExistingDelayedTasksAfterShutdownPolicy(executeExistingDelayedTasksAfterShutdownPolicy);
+		}
+		else if (executeExistingDelayedTasksAfterShutdownPolicy && this.scheduledExecutor != null) {
+			logger.debug("Could not apply execute-existing-delayed-tasks-after-shutdown policy - not a ScheduledThreadPoolExecutor");
+		}
+	}
+
 	/**
 	 * Set a custom {@link ErrorHandler} strategy.
 	 */