Fix tests for executorService.shutdown()

Even if `Executors.newSingleThreadExecutor()` returns a `FinalizableDelegatedExecutorService`,
an instance is kept in the memory until JVM exists.
That may lead to memory leak since we have a lot of threads in memory.

(cherry picked from commit fdac8f1634)

spring-integration-core/src/test/java/org/springframework/integration/aggregator/FluxAggregatorMessageHandlerTests.java

@@ -19,13 +19,13 @@ package org.springframework.integration.aggregator;
 import java.time.Duration;
 import java.util.List;
 import java.util.Objects;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 
 import org.assertj.core.api.InstanceOfAssertFactories;
 import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.condition.DisabledIfEnvironmentVariable;
 import reactor.core.publisher.Flux;
 import reactor.test.StepVerifier;
 
@@ -156,8 +156,6 @@ class FluxAggregatorMessageHandlerTests {
 	}
 
 	@Test
-	@DisabledIfEnvironmentVariable(named = "bamboo_buildKey", matches = ".*?",
-			disabledReason = "Timing is too short for CI")
 	void testWindowTimespan() {
 		QueueChannel resultChannel = new QueueChannel();
 		FluxAggregatorMessageHandler fluxAggregatorMessageHandler = new FluxAggregatorMessageHandler();
@@ -165,18 +163,18 @@ class FluxAggregatorMessageHandlerTests {
 		fluxAggregatorMessageHandler.setWindowTimespan(Duration.ofMillis(100));
 		fluxAggregatorMessageHandler.start();
 
-		Executors.newSingleThreadExecutor()
-				.submit(() -> {
-					for (int i = 0; i < 10; i++) {
-						Message<?> messageToAggregate =
-								MessageBuilder.withPayload(i)
-										.setCorrelationId("1")
-										.build();
-						fluxAggregatorMessageHandler.handleMessage(messageToAggregate);
-						Thread.sleep(20);
-					}
-					return null;
-				});
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		executorService.submit(() -> {
+			for (int i = 0; i < 10; i++) {
+				Message<?> messageToAggregate =
+						MessageBuilder.withPayload(i)
+								.setCorrelationId("1")
+								.build();
+				fluxAggregatorMessageHandler.handleMessage(messageToAggregate);
+				Thread.sleep(20);
+			}
+			return null;
+		});
 
 		Message<?> result = resultChannel.receive(10_000);
 		assertThat(result).isNotNull();
@@ -211,6 +209,8 @@ class FluxAggregatorMessageHandlerTests {
 				.doesNotContain(0, 1);
 
 		fluxAggregatorMessageHandler.stop();
+
+		executorService.shutdown();
 	}
 
 	@Test

spring-integration-core/src/test/java/org/springframework/integration/channel/config/ThreadLocalChannelParserTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -19,12 +19,11 @@ package org.springframework.integration.channel.config;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.Executor;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Qualifier;
@@ -32,8 +31,7 @@ import org.springframework.integration.config.TestChannelInterceptor;
 import org.springframework.messaging.PollableChannel;
 import org.springframework.messaging.support.GenericMessage;
 import org.springframework.test.annotation.DirtiesContext;
-import org.springframework.test.context.ContextConfiguration;
-import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -42,8 +40,7 @@ import static org.assertj.core.api.Assertions.assertThat;
  * @author Dave Syer
  * @author Artem Bilan
  */
-@RunWith(SpringJUnit4ClassRunner.class)
-@ContextConfiguration
+@SpringJUnitConfig
 @DirtiesContext
 public class ThreadLocalChannelParserTests {
 
@@ -58,28 +55,29 @@ public class ThreadLocalChannelParserTests {
 
 	@Test
 	public void testSendInAnotherThread() throws Exception {
-		simpleChannel.send(new GenericMessage<String>("test"));
-		Executor otherThreadExecutor = Executors.newSingleThreadExecutor();
+		simpleChannel.send(new GenericMessage<>("test"));
+		ExecutorService otherThreadExecutor = Executors.newSingleThreadExecutor();
 		final CountDownLatch latch = new CountDownLatch(1);
 		otherThreadExecutor.execute(() -> {
-			simpleChannel.send(new GenericMessage<String>("crap"));
+			simpleChannel.send(new GenericMessage<>("crap"));
 			latch.countDown();
 		});
 		assertThat(latch.await(10, TimeUnit.SECONDS)).isTrue();
 		assertThat(simpleChannel.receive(10).getPayload()).isEqualTo("test");
 		// Message sent on another thread is not collected here
-		assertThat(simpleChannel.receive(10)).isEqualTo(null);
+		assertThat(simpleChannel.receive(1)).isEqualTo(null);
+		otherThreadExecutor.shutdown();
 	}
 
 	@Test
 	public void testReceiveInAnotherThread() throws Exception {
-		simpleChannel.send(new GenericMessage<String>("test-1.1"));
-		simpleChannel.send(new GenericMessage<String>("test-1.2"));
-		simpleChannel.send(new GenericMessage<String>("test-1.3"));
-		channelWithInterceptor.send(new GenericMessage<String>("test-2.1"));
-		channelWithInterceptor.send(new GenericMessage<String>("test-2.2"));
-		Executor otherThreadExecutor = Executors.newSingleThreadExecutor();
-		final List<Object> otherThreadResults = new ArrayList<Object>();
+		simpleChannel.send(new GenericMessage<>("test-1.1"));
+		simpleChannel.send(new GenericMessage<>("test-1.2"));
+		simpleChannel.send(new GenericMessage<>("test-1.3"));
+		channelWithInterceptor.send(new GenericMessage<>("test-2.1"));
+		channelWithInterceptor.send(new GenericMessage<>("test-2.2"));
+		ExecutorService otherThreadExecutor = Executors.newSingleThreadExecutor();
+		final List<Object> otherThreadResults = new ArrayList<>();
 		final CountDownLatch latch = new CountDownLatch(2);
 		otherThreadExecutor.execute(() -> {
 			otherThreadResults.add(simpleChannel.receive(0));
@@ -100,12 +98,14 @@ public class ThreadLocalChannelParserTests {
 		assertThat(channelWithInterceptor.receive(0).getPayload()).isEqualTo("test-2.1");
 		assertThat(channelWithInterceptor.receive(0).getPayload()).isEqualTo("test-2.2");
 		assertThat(channelWithInterceptor.receive(0)).isNull();
+
+		otherThreadExecutor.shutdown();
 	}
 
 	@Test
 	public void testInterceptor() {
 		int before = interceptor.getSendCount();
-		channelWithInterceptor.send(new GenericMessage<String>("test"));
+		channelWithInterceptor.send(new GenericMessage<>("test"));
 		assertThat(interceptor.getSendCount()).isEqualTo(before + 1);
 	}
 

spring-integration-core/src/test/java/org/springframework/integration/config/xml/GatewayParserTests.java

@@ -20,6 +20,7 @@ import java.time.Duration;
 import java.util.Map;
 import java.util.concurrent.Callable;
 import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
@@ -395,7 +396,8 @@ public class GatewayParserTests {
 	}
 
 	private void startResponder(final PollableChannel requestChannel, final MessageChannel replyChannel) {
-		Executors.newSingleThreadExecutor().execute(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		executorService.execute(() -> {
 			Message<?> request = requestChannel.receive(60000);
 			assertThat(request).as("Request not received").isNotNull();
 			Message<?> reply = MessageBuilder.fromMessage(request)
@@ -405,7 +407,7 @@ public class GatewayParserTests {
 				payload = CompletableFuture.completedFuture(reply);
 			}
 			else if (request.getPayload().equals("flowCompletable")) {
-				payload = CompletableFuture.<String>completedFuture("SYNC_COMPLETABLE");
+				payload = CompletableFuture.completedFuture("SYNC_COMPLETABLE");
 			}
 			else if (request.getPayload().equals("flowCustomCompletable")) {
 				MyCompletableFuture myCompletableFuture1 = new MyCompletableFuture();
@@ -427,6 +429,7 @@ public class GatewayParserTests {
 			}
 			replyChannel.send(reply);
 		});
+		executorService.shutdown();
 	}
 
 	@SuppressWarnings("unused")

spring-integration-core/src/test/java/org/springframework/integration/core/AsyncMessagingTemplateTests.java

@@ -18,6 +18,7 @@ package org.springframework.integration.core;
 
 import java.util.concurrent.CancellationException;
 import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
@@ -432,8 +433,8 @@ public class AsyncMessagingTemplateTests {
 	}
 
 	private static void sendMessageAfterDelay(MessageChannel channel, GenericMessage<String> message, int delay) {
-		Executors.newSingleThreadExecutor()
-				.execute(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		executorService.execute(() -> {
 					try {
 						Thread.sleep(delay);
 					}
@@ -443,6 +444,7 @@ public class AsyncMessagingTemplateTests {
 					}
 					channel.send(message);
 				});
+		executorService.shutdown();
 	}
 
 	private static class EchoHandler extends AbstractReplyProducingMessageHandler {

spring-integration-file/src/test/java/org/springframework/integration/file/filters/PersistentAcceptOnceFileListFilterExternalStoreTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2022 the original author or authors.
+ * Copyright 2014-2024 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.
@@ -20,6 +20,7 @@ import java.io.File;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
@@ -48,6 +49,7 @@ import static org.assertj.core.api.Assertions.assertThat;
  * @author Artem Bilan
  * @author Bojan Vukasovic
  * @author Artem Vozhdayenko
+ *
  * @since 4.0
  */
 public class PersistentAcceptOnceFileListFilterExternalStoreTests implements RedisContainerTest {
@@ -139,7 +141,8 @@ public class PersistentAcceptOnceFileListFilterExternalStoreTests implements Red
 		suspend.set(true);
 		assertThat(file.setLastModified(file.lastModified() + 5000L)).isTrue();
 
-		Future<Integer> result = Executors.newSingleThreadExecutor()
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		Future<Integer> result = executorService
 				.submit(() -> filter.filterFiles(new File[] {file}).size());
 		assertThat(latch2.await(10, TimeUnit.SECONDS)).isTrue();
 		store.put("foo:" + file.getAbsolutePath(), "43");
@@ -149,6 +152,7 @@ public class PersistentAcceptOnceFileListFilterExternalStoreTests implements Red
 
 		assertThat(file.delete()).isTrue();
 		filter.close();
+		executorService.shutdown();
 	}
 
 }

spring-integration-file/src/test/java/org/springframework/integration/file/filters/PersistentAcceptOnceFileListFilterTests.java

@@ -22,6 +22,7 @@ import java.io.Flushable;
 import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
@@ -82,8 +83,8 @@ public class PersistentAcceptOnceFileListFilterTests extends AcceptOnceFileListF
 		suspend.set(true);
 		file.setLastModified(file.lastModified() + 5000L);
 
-		Future<Integer> result = Executors.newSingleThreadExecutor()
-				.submit(() -> filter.filterFiles(new File[] {file}).size());
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		Future<Integer> result = executorService.submit(() -> filter.filterFiles(new File[] {file}).size());
 		assertThat(latch2.await(10, TimeUnit.SECONDS)).isTrue();
 		store.put("foo:" + file.getAbsolutePath(), "43");
 		latch1.countDown();
@@ -92,6 +93,7 @@ public class PersistentAcceptOnceFileListFilterTests extends AcceptOnceFileListF
 
 		file.delete();
 		filter.close();
+		executorService.shutdown();
 	}
 
 	@Override

spring-integration-hazelcast/src/test/java/org/springframework/integration/hazelcast/lock/HazelcastLockRegistryTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 the original author or authors.
+ * Copyright 2017-2024 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.
@@ -17,6 +17,7 @@
 package org.springframework.integration.hazelcast.lock;
 
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
@@ -28,8 +29,8 @@ import com.hazelcast.core.Hazelcast;
 import com.hazelcast.core.HazelcastInstance;
 import com.hazelcast.cp.lock.FencedLock;
 import com.hazelcast.instance.impl.HazelcastInstanceFactory;
-import org.junit.AfterClass;
-import org.junit.Test;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -46,7 +47,7 @@ public class HazelcastLockRegistryTests {
 
 	private static final HazelcastInstance instance = Hazelcast.newHazelcastInstance(CONFIG);
 
-	@AfterClass
+	@AfterAll
 	public static void destroy() {
 		HazelcastInstanceFactory.terminateAll();
 	}
@@ -144,7 +145,8 @@ public class HazelcastLockRegistryTests {
 		lock1.lockInterruptibly();
 		AtomicBoolean locked = new AtomicBoolean();
 		CountDownLatch latch = new CountDownLatch(1);
-		Future<Object> result = Executors.newSingleThreadExecutor().submit(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		Future<Object> result = executorService.submit(() -> {
 			Lock lock2 = registry.obtain("foo");
 			locked.set(lock2.tryLock(200, TimeUnit.MILLISECONDS));
 			latch.countDown();
@@ -162,6 +164,7 @@ public class HazelcastLockRegistryTests {
 		Object ise = result.get(10, TimeUnit.SECONDS);
 		assertThat(ise).isInstanceOf(IllegalMonitorStateException.class);
 		assertThat(((Exception) ise).getMessage()).contains("Current thread is not owner of the lock!");
+		executorService.shutdown();
 	}
 
 	@Test
@@ -173,7 +176,8 @@ public class HazelcastLockRegistryTests {
 		CountDownLatch latch2 = new CountDownLatch(1);
 		CountDownLatch latch3 = new CountDownLatch(1);
 		lock1.lockInterruptibly();
-		Executors.newSingleThreadExecutor().execute(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		executorService.execute(() -> {
 			Lock lock2 = registry.obtain("foo");
 			try {
 				latch1.countDown();
@@ -195,6 +199,7 @@ public class HazelcastLockRegistryTests {
 		latch2.countDown();
 		assertThat(latch3.await(10, TimeUnit.SECONDS)).isTrue();
 		assertThat(locked.get()).isTrue();
+		executorService.shutdown();
 	}
 
 	@Test
@@ -207,7 +212,8 @@ public class HazelcastLockRegistryTests {
 		CountDownLatch latch2 = new CountDownLatch(1);
 		CountDownLatch latch3 = new CountDownLatch(1);
 		lock1.lockInterruptibly();
-		Executors.newSingleThreadExecutor().execute(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		executorService.execute(() -> {
 			Lock lock2 = registry2.obtain("foo");
 			try {
 				latch1.countDown();
@@ -229,6 +235,7 @@ public class HazelcastLockRegistryTests {
 		latch2.countDown();
 		assertThat(latch3.await(10, TimeUnit.SECONDS)).isTrue();
 		assertThat(locked.get()).isTrue();
+		executorService.shutdown();
 	}
 
 	@Test
@@ -238,7 +245,8 @@ public class HazelcastLockRegistryTests {
 		lock.lockInterruptibly();
 		final AtomicBoolean locked = new AtomicBoolean();
 		final CountDownLatch latch = new CountDownLatch(1);
-		Future<Object> result = Executors.newSingleThreadExecutor().submit(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		Future<Object> result = executorService.submit(() -> {
 			try {
 				lock.unlock();
 			}
@@ -254,6 +262,7 @@ public class HazelcastLockRegistryTests {
 		Object imse = result.get(10, TimeUnit.SECONDS);
 		assertThat(imse).isInstanceOf(IllegalMonitorStateException.class);
 		assertThat(((Exception) imse).getMessage()).contains("Current thread is not owner of the lock!");
+		executorService.shutdown();
 	}
 
 	@Test

spring-integration-http/src/test/java/org/springframework/integration/http/inbound/HttpRequestHandlingControllerTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -17,6 +17,7 @@
 package org.springframework.integration.http.inbound;
 
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
@@ -357,7 +358,8 @@ public class HttpRequestHandlingControllerTests extends AbstractHttpInboundTests
 		MockHttpServletResponse response = new MockHttpServletResponse();
 		final AtomicInteger active = new AtomicInteger();
 		final AtomicBoolean expected503 = new AtomicBoolean();
-		Executors.newSingleThreadExecutor().execute(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		executorService.execute(() -> {
 			try {
 				// wait for the active thread
 				latch2.await(10, TimeUnit.SECONDS);
@@ -387,6 +389,7 @@ public class HttpRequestHandlingControllerTests extends AbstractHttpInboundTests
 		Object reply = modelAndView.getModel().get("reply");
 		assertThat(reply).isNotNull();
 		assertThat(reply).isEqualTo("HELLO");
+		executorService.shutdown();
 	}
 
 	@Test

spring-integration-kafka/src/test/java/org/springframework/integration/kafka/config/xml/KafkaOutboundAdapterParserTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2022 the original author or authors.
+ * Copyright 2013-2024 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.
@@ -19,6 +19,7 @@ package org.springframework.integration.kafka.config.xml;
 import java.time.Duration;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeoutException;
 
@@ -125,8 +126,8 @@ class KafkaOutboundAdapterParserTests {
 		handler.setTimeoutBuffer(200);
 		handler.setTopicExpression(new LiteralExpression("foo"));
 
-		Executors.newSingleThreadExecutor()
-				.submit(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		executorService.submit(() -> {
 					RuntimeException exception = new RuntimeException("Async Producer Mock exception");
 					while (!mockProducer.errorNext(exception)) {
 						Thread.sleep(100);
@@ -146,6 +147,8 @@ class KafkaOutboundAdapterParserTests {
 				.isThrownBy(() -> handler.handleMessage(new GenericMessage<>("foo")))
 				.withCauseInstanceOf(TimeoutException.class)
 				.withStackTraceContaining("Timeout waiting for response from KafkaProducer");
+
+		executorService.shutdown();
 	}
 
 }

spring-integration-redis/src/test/java/org/springframework/integration/redis/util/AggregatorWithRedisLocksTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2022 the original author or authors.
+ * Copyright 2014-2024 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.
@@ -20,6 +20,7 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
@@ -88,8 +89,9 @@ class AggregatorWithRedisLocksTests implements RedisContainerTest {
 	@Test
 	void testLockSingleGroup() throws Exception {
 		this.releaseStrategy.reset(1);
-		Executors.newSingleThreadExecutor().execute(asyncSend("foo", 1, 1));
-		Executors.newSingleThreadExecutor().execute(asyncSend("bar", 2, 1));
+		ExecutorService executorService = Executors.newCachedThreadPool();
+		executorService.execute(asyncSend("foo", 1, 1));
+		executorService.execute(asyncSend("bar", 2, 1));
 		assertThat(this.releaseStrategy.latch2.await(10, TimeUnit.SECONDS)).isTrue();
 		assertThat(this.template.keys("aggregatorWithRedisLocksTests:*")).hasSize(1);
 		this.releaseStrategy.latch1.countDown();
@@ -98,17 +100,19 @@ class AggregatorWithRedisLocksTests implements RedisContainerTest {
 		this.assertNoLocksAfterTest();
 		assertThat(this.exception)
 				.as("Unexpected exception:" + (this.exception != null ? this.exception.toString() : "")).isNull();
+		executorService.shutdown();
 	}
 
 	@Test
 	void testLockThreeGroups() throws Exception {
 		this.releaseStrategy.reset(3);
-		Executors.newSingleThreadExecutor().execute(asyncSend("foo", 1, 1));
-		Executors.newSingleThreadExecutor().execute(asyncSend("bar", 2, 1));
-		Executors.newSingleThreadExecutor().execute(asyncSend("foo", 1, 2));
-		Executors.newSingleThreadExecutor().execute(asyncSend("bar", 2, 2));
-		Executors.newSingleThreadExecutor().execute(asyncSend("foo", 1, 3));
-		Executors.newSingleThreadExecutor().execute(asyncSend("bar", 2, 3));
+		ExecutorService executorService = Executors.newCachedThreadPool();
+		executorService.execute(asyncSend("foo", 1, 1));
+		executorService.execute(asyncSend("bar", 2, 1));
+		executorService.execute(asyncSend("foo", 1, 2));
+		executorService.execute(asyncSend("bar", 2, 2));
+		executorService.execute(asyncSend("foo", 1, 3));
+		executorService.execute(asyncSend("bar", 2, 3));
 		assertThat(this.releaseStrategy.latch2.await(10, TimeUnit.SECONDS)).isTrue();
 		assertThat(this.template.keys("aggregatorWithRedisLocksTests:*")).hasSize(3);
 		this.releaseStrategy.latch1.countDown();
@@ -121,13 +125,15 @@ class AggregatorWithRedisLocksTests implements RedisContainerTest {
 		this.assertNoLocksAfterTest();
 		assertThat(this.exception)
 				.as("Unexpected exception:" + (this.exception != null ? this.exception.toString() : "")).isNull();
+		executorService.shutdown();
 	}
 
 	@RepeatedTest(10)
 	void testDistributedAggregator() throws Exception {
 		this.releaseStrategy.reset(1);
-		Executors.newSingleThreadExecutor().execute(asyncSend("foo", 1, 1));
-		Executors.newSingleThreadExecutor().execute(() -> {
+		ExecutorService executorService = Executors.newCachedThreadPool();
+		executorService.execute(asyncSend("foo", 1, 1));
+		executorService.execute(() -> {
 			try {
 				in2.send(new GenericMessage<>("bar", stubHeaders(2, 2, 1)));
 			}
@@ -143,6 +149,7 @@ class AggregatorWithRedisLocksTests implements RedisContainerTest {
 		this.assertNoLocksAfterTest();
 		assertThat(this.exception)
 				.as("Unexpected exception:" + (this.exception != null ? this.exception.toString() : "")).isNull();
+		executorService.shutdown();
 	}
 
 	private void assertNoLocksAfterTest() throws Exception {

spring-integration-redis/src/test/java/org/springframework/integration/redis/util/RedisLockRegistryTests.java

@@ -228,7 +228,8 @@ class RedisLockRegistryTests implements RedisContainerTest {
 		lock1.lockInterruptibly();
 		final AtomicBoolean locked = new AtomicBoolean();
 		final CountDownLatch latch = new CountDownLatch(1);
-		Future<Object> result = Executors.newSingleThreadExecutor().submit(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		Future<Object> result = executorService.submit(() -> {
 			Lock lock2 = registry.obtain("foo");
 			locked.set(lock2.tryLock(200, TimeUnit.MILLISECONDS));
 			latch.countDown();
@@ -249,6 +250,7 @@ class RedisLockRegistryTests implements RedisContainerTest {
 		registry.expireUnusedOlderThan(-1000);
 		assertThat(getRedisLockRegistryLocks(registry)).isEmpty();
 		registry.destroy();
+		executorService.shutdown();
 	}
 
 	@ParameterizedTest
@@ -263,7 +265,8 @@ class RedisLockRegistryTests implements RedisContainerTest {
 		CountDownLatch latch3 = new CountDownLatch(1);
 		lock1.lockInterruptibly();
 		assertThat(getRedisLockRegistryLocks(registry)).hasSize(1);
-		Executors.newSingleThreadExecutor().execute(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		executorService.execute(() -> {
 			Lock lock2 = registry.obtain("foo");
 			try {
 				latch1.countDown();
@@ -289,6 +292,7 @@ class RedisLockRegistryTests implements RedisContainerTest {
 		registry.expireUnusedOlderThan(-1000);
 		assertThat(getRedisLockRegistryLocks(registry)).isEmpty();
 		registry.destroy();
+		executorService.shutdown();
 	}
 
 	@ParameterizedTest
@@ -305,7 +309,8 @@ class RedisLockRegistryTests implements RedisContainerTest {
 		CountDownLatch latch3 = new CountDownLatch(1);
 		lock1.lockInterruptibly();
 		assertThat(getRedisLockRegistryLocks(registry1)).hasSize(1);
-		Executors.newSingleThreadExecutor().execute(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		executorService.execute(() -> {
 			Lock lock2 = registry2.obtain("foo");
 			try {
 				latch1.countDown();
@@ -340,6 +345,7 @@ class RedisLockRegistryTests implements RedisContainerTest {
 		assertThat(getRedisLockRegistryLocks(registry2)).isEmpty();
 		registry1.destroy();
 		registry2.destroy();
+		executorService.shutdown();
 	}
 
 	@ParameterizedTest
@@ -351,7 +357,8 @@ class RedisLockRegistryTests implements RedisContainerTest {
 		lock.lockInterruptibly();
 		AtomicBoolean locked = new AtomicBoolean();
 		CountDownLatch latch = new CountDownLatch(1);
-		Future<Object> result = Executors.newSingleThreadExecutor().submit(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		Future<Object> result = executorService.submit(() -> {
 			try {
 				lock.unlock();
 			}
@@ -370,6 +377,7 @@ class RedisLockRegistryTests implements RedisContainerTest {
 		registry.expireUnusedOlderThan(-1000);
 		assertThat(getRedisLockRegistryLocks(registry)).isEmpty();
 		registry.destroy();
+		executorService.shutdown();
 	}
 
 	@ParameterizedTest
@@ -481,7 +489,8 @@ class RedisLockRegistryTests implements RedisContainerTest {
 
 		Long expire = getExpire(registry, "foo");
 
-		Future<Object> result = Executors.newSingleThreadExecutor().submit(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		Future<Object> result = executorService.submit(() -> {
 			Lock lock2 = registry.obtain("foo");
 			assertThat(lock2.tryLock()).isFalse();
 			return null;
@@ -490,6 +499,7 @@ class RedisLockRegistryTests implements RedisContainerTest {
 		assertThat(getExpire(registry, "foo")).isEqualTo(expire);
 		lock.unlock();
 		registry.destroy();
+		executorService.shutdown();
 	}
 
 	@ParameterizedTest

spring-integration-sftp/src/test/java/org/springframework/integration/sftp/outbound/SftpServerOutboundTests.java

@@ -28,6 +28,7 @@ import java.io.UncheckedIOException;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 import java.util.regex.Matcher;
@@ -426,7 +427,8 @@ public class SftpServerOutboundTests extends SftpTestSupport {
 		PipedOutputStream out2 = new PipedOutputStream(pipe2);
 		final CountDownLatch latch1 = new CountDownLatch(1);
 		final CountDownLatch latch2 = new CountDownLatch(1);
-		Executors.newSingleThreadExecutor().execute(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		executorService.execute(() -> {
 			try {
 				session1.write(pipe1, "foo.txt");
 			}
@@ -435,7 +437,7 @@ public class SftpServerOutboundTests extends SftpTestSupport {
 			}
 			latch1.countDown();
 		});
-		Executors.newSingleThreadExecutor().execute(() -> {
+		executorService.execute(() -> {
 			try {
 				session2.write(pipe2, "bar.txt");
 			}
@@ -465,6 +467,7 @@ public class SftpServerOutboundTests extends SftpTestSupport {
 		session2.remove("bar.txt");
 		session1.close();
 		session2.close();
+		executorService.shutdown();
 	}
 
 	@Test

spring-integration-zookeeper/src/test/java/org/springframework/integration/zookeeper/lock/ZkLockRegistryTests.java

@@ -146,7 +146,8 @@ public class ZkLockRegistryTests extends ZookeeperTestSupport {
 		lock1.lockInterruptibly();
 		final AtomicBoolean locked = new AtomicBoolean();
 		final CountDownLatch latch = new CountDownLatch(1);
-		Future<Object> result = Executors.newSingleThreadExecutor().submit(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		Future<Object> result = executorService.submit(() -> {
 			Lock lock2 = registry.obtain("foo");
 			locked.set(lock2.tryLock(200, TimeUnit.MILLISECONDS));
 			latch.countDown();
@@ -165,6 +166,7 @@ public class ZkLockRegistryTests extends ZookeeperTestSupport {
 		assertThat(ise).isInstanceOf(IllegalMonitorStateException.class);
 		assertThat(((Exception) ise).getMessage()).contains("You do not own");
 		registry.destroy();
+		executorService.shutdown();
 	}
 
 	@Test
@@ -176,7 +178,8 @@ public class ZkLockRegistryTests extends ZookeeperTestSupport {
 		final CountDownLatch latch2 = new CountDownLatch(1);
 		final CountDownLatch latch3 = new CountDownLatch(1);
 		lock1.lockInterruptibly();
-		Executors.newSingleThreadExecutor().execute(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		executorService.execute(() -> {
 			Lock lock2 = registry.obtain("foo");
 			try {
 				latch1.countDown();
@@ -199,6 +202,7 @@ public class ZkLockRegistryTests extends ZookeeperTestSupport {
 		assertThat(latch3.await(10, TimeUnit.SECONDS)).isTrue();
 		assertThat(locked.get()).isTrue();
 		registry.destroy();
+		executorService.shutdown();
 	}
 
 	@Test
@@ -211,7 +215,8 @@ public class ZkLockRegistryTests extends ZookeeperTestSupport {
 		final CountDownLatch latch2 = new CountDownLatch(1);
 		final CountDownLatch latch3 = new CountDownLatch(1);
 		lock1.lockInterruptibly();
-		Executors.newSingleThreadExecutor().execute(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		executorService.execute(() -> {
 			Lock lock2 = registry2.obtain("foo");
 			try {
 				latch1.countDown();
@@ -235,6 +240,7 @@ public class ZkLockRegistryTests extends ZookeeperTestSupport {
 		assertThat(locked.get()).isTrue();
 		registry1.destroy();
 		registry2.destroy();
+		executorService.shutdown();
 	}
 
 	@Test
@@ -244,7 +250,8 @@ public class ZkLockRegistryTests extends ZookeeperTestSupport {
 		lock.lockInterruptibly();
 		final AtomicBoolean locked = new AtomicBoolean();
 		final CountDownLatch latch = new CountDownLatch(1);
-		Future<Object> result = Executors.newSingleThreadExecutor().submit(() -> {
+		ExecutorService executorService = Executors.newSingleThreadExecutor();
+		Future<Object> result = executorService.submit(() -> {
 			try {
 				lock.unlock();
 			}
@@ -261,6 +268,7 @@ public class ZkLockRegistryTests extends ZookeeperTestSupport {
 		assertThat(imse).isInstanceOf(IllegalMonitorStateException.class);
 		assertThat(((Exception) imse).getMessage()).contains("You do not own");
 		registry.destroy();
+		executorService.shutdown();
 	}
 
 	@Test