GH-9618: Remove usage of ListenableFuture

Fixes: #9618

Author: artembilan

spring-integration-core/src/main/java/org/springframework/integration/gateway/GatewayProxyFactoryBean.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2024 the original author or authors.
+ * Copyright 2002-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -522,7 +522,6 @@ public T getObject() {
 
 	@Override
 	@Nullable
-	@SuppressWarnings("removal")
 	public Object invoke(final MethodInvocation invocation) throws Throwable { // NOSONAR
 		Method method = invocation.getMethod();
 		Class<?> returnType;
@@ -541,13 +540,6 @@ public Object invoke(final MethodInvocation invocation) throws Throwable { // NO
 			else if (CompletableFuture.class.equals(returnType)) { // exact
 				return CompletableFuture.supplyAsync(invoker, this.asyncExecutor);
 			}
-			else if (org.springframework.util.concurrent.ListenableFuture.class.equals(returnType)) {
-				logger.warn("The 'org.springframework.util.concurrent.ListenableFuture' is deprecated for removal." +
-						"The 'CompletableFuture' is recommended to be used instead." +
-						"The 'ListenableFuture' support will be removed in Spring Integration 6.5.");
-				return ((org.springframework.core.task.AsyncListenableTaskExecutor) this.asyncExecutor)
-						.submitListenable(invoker::get);
-			}
 			else if (Future.class.isAssignableFrom(returnType)) {
 				logger.debug(() -> "AsyncTaskExecutor submit*() return types are incompatible with the method return " +
 						"type; running on calling thread; the downstream flow must return the required Future: "

spring-integration-core/src/main/java/org/springframework/integration/handler/AbstractMessageProducingHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2024 the original author or authors.
+ * Copyright 2014-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -321,7 +321,6 @@ else if (reply instanceof AbstractIntegrationMessageBuilder<?>) {
 		return replyChannel;
 	}
 
-	@SuppressWarnings("removal")
 	private void doProduceOutput(Message<?> requestMessage, MessageHeaders requestHeaders, Object reply,
 			@Nullable Object replyChannelArg) {
 
@@ -331,9 +330,7 @@ private void doProduceOutput(Message<?> requestMessage, MessageHeaders requestHe
 		}
 
 		if (this.async) {
-			boolean isFutureReply =
-					reply instanceof org.springframework.util.concurrent.ListenableFuture<?> ||
-							reply instanceof CompletableFuture<?>;
+			boolean isFutureReply = reply instanceof CompletableFuture<?>;
 
 			ReactiveAdapter reactiveAdapter = null;
 			if (!isFutureReply) {
@@ -366,7 +363,7 @@ private Publisher<?> toPublisherReply(Object reply, @Nullable ReactiveAdapter re
 			return reactiveAdapter.toPublisher(reply);
 		}
 		else {
-			return Mono.fromFuture(toCompletableFuture(reply));
+			return Mono.fromFuture((CompletableFuture<?>) reply);
 		}
 	}
 
@@ -415,20 +412,7 @@ via whenComplete() callback. So, when value is set into the Future, it is availa
 			return replyFuture;
 		}
 		else {
-			return toCompletableFuture(reply);
-		}
-	}
-
-	@SuppressWarnings("removal")
-	private CompletableFuture<?> toCompletableFuture(Object reply) {
-		if (reply instanceof CompletableFuture<?> completableFuture) {
-			return completableFuture;
-		}
-		else {
-			logger.warn("The 'org.springframework.util.concurrent.ListenableFuture' is deprecated for removal." +
-					"The 'CompletableFuture' is recommended to be used instead." +
-					"The 'ListenableFuture' support will be removed in Spring Integration 6.5.");
-			return ((org.springframework.util.concurrent.ListenableFuture<?>) reply).completable();
+			return (CompletableFuture<?>) reply;
 		}
 	}
 

src/reference/antora/modules/ROOT/pages/whats-new.adoc

@@ -13,3 +13,8 @@ If you are interested in more details, see the Issue Tracker tickets that were r
 
 In general the project has been moved to the latest dependency versions.
 
+[[x6.5-general]]
+== General Changes
+
+The deprecated previously usage of `org.springframework.util.concurrent.ListenableFuture` has been removed in favor of `CompletableFuture`.
+