Fix deprecation errors & warnings

* Add `<@nullable Object>` for API with nullable based on generics
* Migrate to `org.springframework.expression.spel.support.MapAccessor` from
deprecated `org.springframework.context.expression.MapAccessor`
* Improve `TestUtils` to register a `nullChannel` as a `Queue`
* Improve `TestApplicationContextAware` to clean up `nullChannel` from test context before test class is run
* `IntegrationFlowTests.retryAdvice()` to avoid a long delay for the whole test suite
* Fix many failing tests for `TestApplicationContextAware` or manual `GenericApplicationContext`

Author: artembilan

spring-integration-amqp/src/main/java/org/springframework/integration/amqp/inbound/AmqpInboundChannelAdapter.java

@@ -382,7 +382,7 @@ public void onMessage(final Message message, @Nullable Channel channel) {
 					final org.springframework.messaging.Message<Object> toSend =
 							createMessageFromAmqp(message, channel);
 					try {
-						this.retryOps.execute(
+						this.retryOps.<@Nullable Object>execute(
 								() -> {
 									AtomicInteger deliveryAttempt = StaticMessageHeaderAccessor.getDeliveryAttempt(toSend);
 									if (deliveryAttempt != null) {
@@ -508,7 +508,7 @@ public void onMessageBatch(List<Message> messages, @Nullable Channel channel) {
 					}
 					else {
 						try {
-							this.retryOps.execute(
+							this.retryOps.<@Nullable Object>execute(
 									() -> {
 										AtomicInteger deliveryAttempt =
 												StaticMessageHeaderAccessor.getDeliveryAttempt(message);

spring-integration-amqp/src/main/java/org/springframework/integration/amqp/inbound/AmqpInboundGateway.java

@@ -366,7 +366,7 @@ public void onMessage(final Message message, @Nullable Channel channel) {
 					org.springframework.messaging.Message<Object> converted = convert(message, channel);
 					if (converted != null) {
 						try {
-							AmqpInboundGateway.this.retryTemplate.execute(() -> {
+							AmqpInboundGateway.this.retryTemplate.<@Nullable Object>execute(() -> {
 								AtomicInteger deliveryAttempt = StaticMessageHeaderAccessor.getDeliveryAttempt(converted);
 								if (deliveryAttempt != null) {
 									deliveryAttempt.incrementAndGet();

spring-integration-amqp/src/main/java/org/springframework/integration/amqp/outbound/AmqpOutboundEndpoint.java

@@ -198,7 +198,7 @@ private void multiSend(Message<?> requestMessage, @Nullable String exchangeName,
 		});
 		RabbitTemplate rabbitTemplateToUse = this.rabbitTemplate;
 		Assert.notNull(rabbitTemplateToUse, "The 'RabbitTemplate' must be provided for multi-send.");
-		rabbitTemplateToUse.invoke(template -> {
+		rabbitTemplateToUse.<@Nullable Object>invoke(template -> {
 			((Iterable<Message<?>>) requestMessage.getPayload())
 					.forEach(message -> doRabbitSend(exchangeName, routingKey, message, null, rabbitTemplateToUse));
 			if (this.waitForConfirm) {

spring-integration-amqp/src/main/java/org/springframework/integration/amqp/support/BoundRabbitChannelAdvice.java

@@ -83,7 +83,7 @@ public BoundRabbitChannelAdvice(RabbitOperations operations, @Nullable Duration
 	@Override
 	public @Nullable Object invoke(MethodInvocation invocation) throws Throwable {
 		try {
-			return this.operations.invoke(operations -> {
+			return this.operations.<@Nullable Object>invoke(operations -> {
 				try {
 					Object result = invocation.proceed();
 					if (this.waitForConfirmsTimeout != null) {

spring-integration-core/src/main/java/org/springframework/integration/config/IntegrationEvaluationContextFactoryBean.java

@@ -24,11 +24,11 @@
 import org.springframework.beans.factory.FactoryBean;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.expression.BeanFactoryResolver;
-import org.springframework.context.expression.MapAccessor;
 import org.springframework.expression.BeanResolver;
 import org.springframework.expression.IndexAccessor;
 import org.springframework.expression.PropertyAccessor;
 import org.springframework.expression.TypeLocator;
+import org.springframework.expression.spel.support.MapAccessor;
 import org.springframework.expression.spel.support.StandardEvaluationContext;
 import org.springframework.expression.spel.support.StandardTypeLocator;
 import org.springframework.integration.context.IntegrationContextUtils;

spring-integration-core/src/main/java/org/springframework/integration/config/IntegrationSimpleEvaluationContextFactoryBean.java

@@ -21,10 +21,10 @@
 import java.util.Map.Entry;
 
 import org.springframework.beans.factory.FactoryBean;
-import org.springframework.context.expression.MapAccessor;
 import org.springframework.expression.IndexAccessor;
 import org.springframework.expression.PropertyAccessor;
 import org.springframework.expression.spel.support.DataBindingPropertyAccessor;
+import org.springframework.expression.spel.support.MapAccessor;
 import org.springframework.expression.spel.support.SimpleEvaluationContext;
 import org.springframework.integration.context.IntegrationContextUtils;
 

spring-integration-core/src/main/java/org/springframework/integration/expression/ExpressionUtils.java

@@ -25,14 +25,14 @@
 import org.jspecify.annotations.Nullable;
 
 import org.springframework.beans.factory.BeanFactory;
-import org.springframework.context.expression.MapAccessor;
 import org.springframework.core.convert.ConversionService;
 import org.springframework.core.io.Resource;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.Expression;
 import org.springframework.expression.ExpressionParser;
 import org.springframework.expression.spel.standard.SpelExpressionParser;
 import org.springframework.expression.spel.support.DataBindingPropertyAccessor;
+import org.springframework.expression.spel.support.MapAccessor;
 import org.springframework.expression.spel.support.SimpleEvaluationContext;
 import org.springframework.expression.spel.support.StandardEvaluationContext;
 import org.springframework.integration.context.IntegrationContextUtils;

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

@@ -158,7 +158,7 @@ public void setNewMessagePredicate(Predicate<Message<?>> newMessagePredicate) {
 		AttributeAccessor retryContext = ErrorMessageUtils.getAttributeAccessor(message, message);
 		try {
 			if (this.stateKeyFunction == null) {
-				return this.retryTemplate.execute(retryCallback);
+				return this.retryTemplate.<@Nullable Object>execute(retryCallback);
 			}
 
 			return statefulRetry(retryCallback, this.stateKeyFunction);
@@ -253,7 +253,7 @@ else if (cause instanceof ThrowableHolderException throwableHolderException) {
 	}
 
 	private record IntegrationRetryCallback(Message<?> messageToTry, ExecutionCallback callback, Object target)
-			implements Retryable<Object> {
+			implements Retryable<@Nullable Object> {
 
 		@Override
 		public @Nullable Object execute() {

spring-integration-core/src/test/java/org/springframework/integration/bus/DirectChannelSubscriptionTests.java

@@ -20,17 +20,16 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
+import org.springframework.context.support.GenericApplicationContext;
 import org.springframework.integration.annotation.MessageEndpoint;
 import org.springframework.integration.annotation.ServiceActivator;
 import org.springframework.integration.channel.DirectChannel;
 import org.springframework.integration.channel.QueueChannel;
 import org.springframework.integration.config.IntegrationRegistrar;
-import org.springframework.integration.context.IntegrationContextUtils;
 import org.springframework.integration.endpoint.EventDrivenConsumer;
 import org.springframework.integration.handler.AbstractReplyProducingMessageHandler;
 import org.springframework.integration.handler.ServiceActivatingHandler;
 import org.springframework.integration.test.util.TestUtils;
-import org.springframework.integration.test.util.TestUtils.TestApplicationContext;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessagingException;
 import org.springframework.messaging.PollableChannel;
@@ -46,7 +45,7 @@
  */
 public class DirectChannelSubscriptionTests {
 
-	private final TestApplicationContext context = TestUtils.createTestApplicationContext();
+	private final GenericApplicationContext context = new GenericApplicationContext();
 
 	private final DirectChannel sourceChannel = new DirectChannel();
 
@@ -55,8 +54,8 @@ public class DirectChannelSubscriptionTests {
 	@BeforeEach
 	public void setupChannels() {
 		new IntegrationRegistrar().registerBeanDefinitions(mock(), this.context.getDefaultListableBeanFactory());
-		this.context.registerChannel("sourceChannel", this.sourceChannel);
-		this.context.registerChannel("targetChannel", this.targetChannel);
+		TestUtils.registerBean("sourceChannel", this.sourceChannel, this.context);
+		TestUtils.registerBean("targetChannel", this.targetChannel, this.context);
 	}
 
 	@AfterEach
@@ -68,9 +67,9 @@ public void tearDown() {
 	public void sendAndReceiveForRegisteredEndpoint() {
 		ServiceActivatingHandler serviceActivator = new ServiceActivatingHandler(new TestBean(), "handle");
 		serviceActivator.setOutputChannel(this.targetChannel);
-		context.registerBean("testServiceActivator", serviceActivator);
+		TestUtils.registerBean("testServiceActivator", serviceActivator, this.context);
 		EventDrivenConsumer endpoint = new EventDrivenConsumer(this.sourceChannel, serviceActivator);
-		context.registerEndpoint("testEndpoint", endpoint);
+		TestUtils.registerBean("testEndpoint", endpoint, this.context);
 		context.refresh();
 		this.sourceChannel.send(new GenericMessage<>("foo"));
 		Message<?> response = this.targetChannel.receive();
@@ -79,7 +78,7 @@ public void sendAndReceiveForRegisteredEndpoint() {
 
 	@Test
 	public void sendAndReceiveForAnnotatedEndpoint() {
-		this.context.registerEndpoint("testEndpoint", new TestEndpoint());
+		TestUtils.registerBean("testEndpoint", new TestEndpoint(), this.context);
 		this.context.refresh();
 
 		this.sourceChannel.send(new GenericMessage<>("foo"));
@@ -98,17 +97,15 @@ public Object handleRequestMessage(Message<?> message) {
 		};
 		handler.setOutputChannel(targetChannel);
 		EventDrivenConsumer endpoint = new EventDrivenConsumer(sourceChannel, handler);
-		this.context.registerEndpoint("testEndpoint", endpoint);
+		TestUtils.registerBean("testEndpoint", endpoint, this.context);
 		this.context.refresh();
 		assertThatExceptionOfType(MessagingException.class)
 				.isThrownBy(() -> this.sourceChannel.send(new GenericMessage<>("foo")));
 	}
 
 	@Test
 	public void exceptionThrownFromAnnotatedEndpoint() {
-		QueueChannel errorChannel = new QueueChannel();
-		this.context.registerChannel(IntegrationContextUtils.ERROR_CHANNEL_BEAN_NAME, errorChannel);
-		this.context.registerEndpoint("testEndpoint", new FailingTestEndpoint());
+		TestUtils.registerBean("testEndpoint", new FailingTestEndpoint(), this.context);
 		this.context.refresh();
 		assertThatExceptionOfType(MessagingException.class)
 				.isThrownBy(() -> this.sourceChannel.send(new GenericMessage<>("foo")));

spring-integration-core/src/test/java/org/springframework/integration/channel/registry/HeaderChannelRegistryTests.java

@@ -19,13 +19,8 @@
 import java.util.Map;
 
 import org.junit.jupiter.api.Test;
-import org.mockito.Mockito;
 
-import org.springframework.beans.factory.BeanFactory;
-import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.context.expression.MapAccessor;
-import org.springframework.expression.spel.support.StandardEvaluationContext;
 import org.springframework.integration.channel.DefaultHeaderChannelRegistry;
 import org.springframework.integration.channel.DirectChannel;
 import org.springframework.integration.channel.MessagePublishingErrorHandler;
@@ -36,7 +31,6 @@
 import org.springframework.integration.support.MessageBuilder;
 import org.springframework.integration.support.MessagingExceptionWrapper;
 import org.springframework.integration.support.channel.BeanFactoryChannelResolver;
-import org.springframework.integration.support.channel.HeaderChannelRegistry;
 import org.springframework.integration.test.support.TestApplicationContextAware;
 import org.springframework.integration.test.util.TestUtils;
 import org.springframework.messaging.Message;
@@ -51,10 +45,6 @@
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
-import static org.mockito.ArgumentMatchers.eq;
-import static org.mockito.Mockito.doAnswer;
-import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.when;
 
 /**
  * @author Gary Russell
@@ -216,28 +206,22 @@ public void testExpire() throws Exception {
 	@Test
 	public void testBFCRWithRegistry() {
 		BeanFactoryChannelResolver resolver = new BeanFactoryChannelResolver();
-		BeanFactory beanFactory = createTestEvaluationContext();
-		when(beanFactory.getBean(IntegrationContextUtils.INTEGRATION_HEADER_CHANNEL_REGISTRY_BEAN_NAME,
-				HeaderChannelRegistry.class))
-				.thenReturn(mock(HeaderChannelRegistry.class));
-		doAnswer(invocation -> {
-			throw new NoSuchBeanDefinitionException("bar");
-		}).when(beanFactory).getBean("foo", MessageChannel.class);
-		resolver.setBeanFactory(beanFactory);
+		TestUtils.registerBean(IntegrationContextUtils.INTEGRATION_HEADER_CHANNEL_REGISTRY_BEAN_NAME,
+				new DefaultHeaderChannelRegistry(), TEST_INTEGRATION_CONTEXT);
+		resolver.setBeanFactory(TEST_INTEGRATION_CONTEXT);
 
 		assertThatExceptionOfType(DestinationResolutionException.class)
 				.isThrownBy(() -> resolver.resolveDestination("foo"))
 				.withMessageContaining("failed to look up MessageChannel with name 'foo' in the BeanFactory.");
+
+		TEST_INTEGRATION_CONTEXT.removeBeanDefinition(
+				IntegrationContextUtils.INTEGRATION_HEADER_CHANNEL_REGISTRY_BEAN_NAME);
 	}
 
 	@Test
 	public void testBFCRNoRegistry() {
 		BeanFactoryChannelResolver resolver = new BeanFactoryChannelResolver();
-		BeanFactory beanFactory = createTestEvaluationContext();
-		doAnswer(invocation -> {
-			throw new NoSuchBeanDefinitionException("bar");
-		}).when(beanFactory).getBean("foo", MessageChannel.class);
-		resolver.setBeanFactory(beanFactory);
+		resolver.setBeanFactory(TEST_INTEGRATION_CONTEXT);
 
 		assertThatExceptionOfType(DestinationResolutionException.class)
 				.isThrownBy(() -> resolver.resolveDestination("foo"))
@@ -252,12 +236,12 @@ public void testRemoveOnGet() {
 		MessageChannel channel = new DirectChannel();
 		String foo = (String) registry.channelToChannelName(channel);
 		Map<?, ?> map = TestUtils.getPropertyValue(registry, "channels", Map.class);
-		assertThat(map.size()).isEqualTo(1);
+		assertThat(map).hasSize(1);
 		assertThat(registry.channelNameToChannel(foo)).isSameAs(channel);
-		assertThat(map.size()).isEqualTo(1);
+		assertThat(map).hasSize(1);
 		registry.setRemoveOnGet(true);
 		assertThat(registry.channelNameToChannel(foo)).isSameAs(channel);
-		assertThat(map.size()).isEqualTo(0);
+		assertThat(map).hasSize(0);
 	}
 
 	public static class Foo extends AbstractReplyProducingMessageHandler {
@@ -282,19 +266,6 @@ protected Object handleRequestMessage(Message<?> requestMessage) {
 
 	}
 
-	private static BeanFactory createTestEvaluationContext() {
-		final String integrationEvaluationContextBeanName = "integrationEvaluationContext";
-		BeanFactory beanFactory = mock(BeanFactory.class);
-		when(beanFactory.containsBean(eq(integrationEvaluationContextBeanName)))
-				.thenReturn(true);
-		StandardEvaluationContext evaluationContext = new StandardEvaluationContext();
-		evaluationContext.addPropertyAccessor(new MapAccessor());
-		when(beanFactory.getBean(eq(integrationEvaluationContextBeanName),
-				Mockito.<Class<StandardEvaluationContext>>any()))
-				.thenReturn(evaluationContext);
-		return beanFactory;
-	}
-
 	public interface Gateway {
 
 		String exchange(String foo);