From cff48fff2d681a97443a2f228e2e34a5900545c9 Mon Sep 17 00:00:00 2001
From: Juergen Hoeller <juergen.hoeller@broadcom.com>
Date: Tue, 24 Feb 2026 17:17:21 +0100
Subject: [PATCH] Reject late-executing tasks after termination waiting

Closes gh-36362
---
 .../core/task/SimpleAsyncTaskExecutor.java    | 27 ++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/spring-core/src/main/java/org/springframework/core/task/SimpleAsyncTaskExecutor.java b/spring-core/src/main/java/org/springframework/core/task/SimpleAsyncTaskExecutor.java
index f8d44c68225..6440e28ceb7 100644
--- a/spring-core/src/main/java/org/springframework/core/task/SimpleAsyncTaskExecutor.java
+++ b/spring-core/src/main/java/org/springframework/core/task/SimpleAsyncTaskExecutor.java
@@ -96,6 +96,8 @@ public class SimpleAsyncTaskExecutor extends CustomizableThreadCreator
 
 	private volatile boolean active = true;
 
+	private volatile boolean cancelled = false;
+
 
 	/**
 	 * Create a new SimpleAsyncTaskExecutor with default thread name prefix.
@@ -389,6 +391,7 @@ public class SimpleAsyncTaskExecutor extends CustomizableThreadCreator
 			Set<Thread> threads = this.activeThreads;
 			if (threads != null) {
 				if (this.cancelRemainingTasksOnClose) {
+					this.cancelled = true;
 					// Early interrupt for remaining tasks on close
 					threads.forEach(Thread::interrupt);
 				}
@@ -402,6 +405,7 @@ public class SimpleAsyncTaskExecutor extends CustomizableThreadCreator
 						catch (InterruptedException ex) {
 							Thread.currentThread().interrupt();
 						}
+						this.cancelled = true;
 					}
 					if (!this.cancelRemainingTasksOnClose) {
 						// Late interrupt for remaining tasks after timeout
@@ -412,6 +416,12 @@ public class SimpleAsyncTaskExecutor extends CustomizableThreadCreator
 		}
 	}
 
+	private void checkCancelled() {
+		if (this.cancelled) {
+			throw new TaskRejectedException(getClass().getSimpleName() + " has cancelled all remaining tasks");
+		}
+	}
+
 
 	/**
 	 * Subclass of the general ConcurrencyThrottleSupport class,
@@ -464,16 +474,27 @@ public class SimpleAsyncTaskExecutor extends CustomizableThreadCreator
 			Thread thread = null;
 			if (threads != null) {
 				thread = Thread.currentThread();
-				threads.add(thread);
+				if (isActive()) {
+					threads.add(thread);
+				}
+				else {
+					synchronized (threads) {
+						checkCancelled();
+						threads.add(thread);
+					}
+				}
 			}
 			try {
 				this.task.run();
 			}
 			finally {
 				if (threads != null) {
-					threads.remove(thread);
-					if (!isActive()) {
+					if (isActive()) {
+						threads.remove(thread);
+					}
+					else {
 						synchronized (threads) {
+							threads.remove(thread);
 							if (threads.isEmpty()) {
 								threads.notify();
 							}