Fix new Sonar smells (#2768)

* Fix new Sonar smells

* Fix some old Sonar smells as well
* Fix Micrometer leaks in the `PollableChannel` when we register
meters, but don't remove them.

* * Fix NPE around `MetricsCaptor` in channels

* * Fix new smells according test report

* * Further Sonar smell fixes

* * More smell fixes for `MessagingMethodInvokerHelper`
* Remove `throws Exception` from `AbstractMessageHandler.destroy()`

* * Fix complexity in the `MessagingMethodInvokerHelper.processInvokeExceptionAndFallbackToExpressionIfAny()`

spring-integration-core/src/main/java/org/springframework/integration/aggregator/AbstractCorrelatingMessageHandler.java

@@ -386,13 +386,10 @@ public abstract class AbstractCorrelatingMessageHandler extends AbstractMessageP
 
 	@Override
 	public MessageChannel getDiscardChannel() {
-		if (this.discardChannelName != null) {
-			synchronized (this) {
-				if (this.discardChannelName != null) {
-					this.discardChannel = getChannelResolver().resolveDestination(this.discardChannelName);
-					this.discardChannelName = null;
-				}
-			}
+		String channelName = this.discardChannelName;
+		if (channelName != null) {
+			this.discardChannel = getChannelResolver().resolveDestination(channelName);
+			this.discardChannelName = null;
 		}
 		return this.discardChannel;
 	}
@@ -449,48 +446,7 @@ public abstract class AbstractCorrelatingMessageHandler extends AbstractMessageP
 		boolean noOutput = true;
 		lock.lockInterruptibly();
 		try {
-			ScheduledFuture<?> scheduledFuture = this.expireGroupScheduledFutures.remove(groupIdUuid);
-			if (scheduledFuture != null) {
-				boolean canceled = scheduledFuture.cancel(true);
-				if (canceled && this.logger.isDebugEnabled()) {
-					this.logger.debug("Cancel 'ScheduledFuture' for MessageGroup with Correlation Key [ "
-							+ correlationKey + "].");
-				}
-			}
-			MessageGroup messageGroup = this.messageStore.getMessageGroup(correlationKey);
-			if (this.sequenceAware) {
-				messageGroup = new SequenceAwareMessageGroup(messageGroup);
-			}
-
-			if (!messageGroup.isComplete() && messageGroup.canAdd(message)) {
-				if (this.logger.isTraceEnabled()) {
-					this.logger.trace("Adding message to group [ " + messageGroup + "]");
-				}
-				messageGroup = this.store(correlationKey, message);
-
-				if (this.releaseStrategy.canRelease(messageGroup)) {
-					Collection<Message<?>> completedMessages = null;
-					try {
-						noOutput = false;
-						completedMessages = completeGroup(message, correlationKey, messageGroup, lock);
-					}
-					finally {
-						// Possible clean (implementation dependency) up
-						// even if there was an exception processing messages
-						afterRelease(messageGroup, completedMessages);
-					}
-					if (!isExpireGroupsUponCompletion() && this.minimumTimeoutForEmptyGroups > 0) {
-						removeEmptyGroupAfterTimeout(messageGroup, this.minimumTimeoutForEmptyGroups);
-					}
-				}
-				else {
-					scheduleGroupToForceComplete(messageGroup);
-				}
-			}
-			else {
-				noOutput = false;
-				discardMessage(message, lock);
-			}
+			noOutput = processMessageForGroup(message, correlationKey, groupIdUuid, lock);
 		}
 		finally {
 			if (noOutput || !this.releaseLockBeforeSend) {
@@ -499,6 +455,57 @@ public abstract class AbstractCorrelatingMessageHandler extends AbstractMessageP
 		}
 	}
 
+	private boolean processMessageForGroup(Message<?> message, Object correlationKey, UUID groupIdUuid, Lock lock) {
+		boolean noOutput = true;
+		cancelScheduledFutureIfAny(correlationKey, groupIdUuid, true);
+		MessageGroup messageGroup = this.messageStore.getMessageGroup(correlationKey);
+		if (this.sequenceAware) {
+			messageGroup = new SequenceAwareMessageGroup(messageGroup);
+		}
+
+		if (!messageGroup.isComplete() && messageGroup.canAdd(message)) {
+			if (this.logger.isTraceEnabled()) {
+				this.logger.trace("Adding message to group [ " + messageGroup + "]");
+			}
+			messageGroup = store(correlationKey, message);
+
+			if (this.releaseStrategy.canRelease(messageGroup)) {
+				Collection<Message<?>> completedMessages = null;
+				try {
+					noOutput = false;
+					completedMessages = completeGroup(message, correlationKey, messageGroup, lock);
+				}
+				finally {
+					// Possible clean (implementation dependency) up
+					// even if there was an exception processing messages
+					afterRelease(messageGroup, completedMessages);
+				}
+				if (!isExpireGroupsUponCompletion() && this.minimumTimeoutForEmptyGroups > 0) {
+					removeEmptyGroupAfterTimeout(messageGroup, this.minimumTimeoutForEmptyGroups);
+				}
+			}
+			else {
+				scheduleGroupToForceComplete(messageGroup);
+			}
+		}
+		else {
+			noOutput = false;
+			discardMessage(message, lock);
+		}
+		return noOutput;
+	}
+
+	private void cancelScheduledFutureIfAny(Object correlationKey, UUID groupIdUuid, boolean mayInterruptIfRunning) {
+		ScheduledFuture<?> scheduledFuture = this.expireGroupScheduledFutures.remove(groupIdUuid);
+		if (scheduledFuture != null) {
+			boolean canceled = scheduledFuture.cancel(mayInterruptIfRunning);
+			if (canceled && this.logger.isDebugEnabled()) {
+				this.logger.debug("Cancel 'ScheduledFuture' for MessageGroup with Correlation Key [ "
+						+ correlationKey + "].");
+			}
+		}
+	}
+
 	protected boolean isExpireGroupsUponCompletion() {
 		return false;
 	}
@@ -606,7 +613,10 @@ public abstract class AbstractCorrelatingMessageHandler extends AbstractMessageP
 	}
 
 	private void discardMessage(Message<?> message) {
-		this.messagingTemplate.send(getDiscardChannel(), message);
+		MessageChannel messageChannel = getDiscardChannel();
+		if (messageChannel != null) {
+			this.messagingTemplate.send(messageChannel, message);
+		}
 	}
 
 	/**
@@ -630,20 +640,14 @@ public abstract class AbstractCorrelatingMessageHandler extends AbstractMessageP
 	protected void forceComplete(MessageGroup group) {
 		Object correlationKey = group.getGroupId();
 		// UUIDConverter is no-op if already converted
-		Lock lock = this.lockRegistry.obtain(UUIDConverter.getUUID(correlationKey).toString());
+		UUID groupId = UUIDConverter.getUUID(correlationKey);
+		Lock lock = this.lockRegistry.obtain(groupId.toString());
 		boolean removeGroup = true;
 		boolean noOutput = true;
 		try {
 			lock.lockInterruptibly();
 			try {
-				ScheduledFuture<?> scheduledFuture =
-						this.expireGroupScheduledFutures.remove(UUIDConverter.getUUID(correlationKey));
-				if (scheduledFuture != null) {
-					boolean canceled = scheduledFuture.cancel(false);
-					if (canceled && this.logger.isDebugEnabled()) {
-						this.logger.debug("Cancel 'forceComplete' scheduling for MessageGroup [ " + group + "].");
-					}
-				}
+				cancelScheduledFutureIfAny(correlationKey, groupId, false);
 				MessageGroup groupNow = group;
 				/*
 				 * If the group argument is not already complete,

spring-integration-core/src/main/java/org/springframework/integration/aggregator/BarrierMessageHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2018 the original author or authors.
+ * Copyright 2015-2019 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.
@@ -45,6 +45,7 @@ import org.springframework.util.Assert;
  * The default output processor is a {@link DefaultAggregatingMessageGroupProcessor}.
  *
  * @author Gary Russell
+ * @author Artem Bilan
  *
  * @since 4.2
  */
@@ -61,10 +62,10 @@ public class BarrierMessageHandler extends AbstractReplyProducingMessageHandler
 
 	private final MessageGroupProcessor messageGroupProcessor;
 
-	private volatile MessageChannel discardChannel;
-
 	private String discardChannelName;
 
+	private MessageChannel discardChannel;
+
 	/**
 	 * Construct an instance with the provided timeout and default correlation and
 	 * output strategies.
@@ -135,8 +136,10 @@ public class BarrierMessageHandler extends AbstractReplyProducingMessageHandler
 	 */
 	@Override
 	public MessageChannel getDiscardChannel() {
-		if (this.discardChannel == null && this.discardChannelName != null && getChannelResolver() != null) {
-			this.discardChannel = getChannelResolver().resolveDestination(this.discardChannelName);
+		String channelName = this.discardChannelName;
+		if (channelName != null) {
+			this.discardChannel = getChannelResolver().resolveDestination(channelName);
+			this.discardChannelName = null;
 		}
 		return this.discardChannel;
 	}
@@ -221,8 +224,9 @@ public class BarrierMessageHandler extends AbstractReplyProducingMessageHandler
 			if (!syncQueue.offer(message, this.timeout, TimeUnit.MILLISECONDS)) {
 				this.logger.error("Suspending thread timed out or did not arrive within timeout for: " + message);
 				this.suspensions.remove(key);
-				if (getDiscardChannel() != null) {
-					this.messagingTemplate.send(getDiscardChannel(), message);
+				MessageChannel messageChannel = getDiscardChannel();
+				if (messageChannel != null) {
+					this.messagingTemplate.send(messageChannel, message);
 				}
 			}
 		}

spring-integration-core/src/main/java/org/springframework/integration/aggregator/ExpressionEvaluatingReleaseStrategy.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -46,7 +46,7 @@ public class ExpressionEvaluatingReleaseStrategy extends AbstractExpressionEvalu
 	 * and return the result (must be boolean).
 	 */
 	public boolean canRelease(MessageGroup messages) {
-		return evaluateExpression(this.expression, messages, Boolean.class);
+		return Boolean.TRUE.equals(evaluateExpression(this.expression, messages, Boolean.class));
 	}
 
 }

spring-integration-core/src/main/java/org/springframework/integration/aggregator/MethodInvokingMessageListProcessor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -34,32 +34,33 @@ import org.springframework.messaging.Message;
  * @author Dave Syer
  * @author Artem Bilan
  * @author Gary Russell
+ *
  * @since 2.0
  */
 public class MethodInvokingMessageListProcessor<T> extends AbstractExpressionEvaluator
 		implements Lifecycle {
 
-	private final MessagingMethodInvokerHelper<T> delegate;
+	private final MessagingMethodInvokerHelper delegate;
 
 	public MethodInvokingMessageListProcessor(Object targetObject, Method method, Class<T> expectedType) {
-		this.delegate = new MessagingMethodInvokerHelper<T>(targetObject, method, expectedType, true);
+		this.delegate = new MessagingMethodInvokerHelper(targetObject, method, expectedType, true);
 	}
 
 	public MethodInvokingMessageListProcessor(Object targetObject, Method method) {
-		this.delegate = new MessagingMethodInvokerHelper<T>(targetObject, method, true);
+		this.delegate = new MessagingMethodInvokerHelper(targetObject, method, true);
 	}
 
 	public MethodInvokingMessageListProcessor(Object targetObject, String methodName, Class<T> expectedType) {
-		this.delegate = new MessagingMethodInvokerHelper<T>(targetObject, methodName,
+		this.delegate = new MessagingMethodInvokerHelper(targetObject, methodName,
 				expectedType, true);
 	}
 
 	public MethodInvokingMessageListProcessor(Object targetObject, String methodName) {
-		this.delegate = new MessagingMethodInvokerHelper<T>(targetObject, methodName, true);
+		this.delegate = new MessagingMethodInvokerHelper(targetObject, methodName, true);
 	}
 
 	public MethodInvokingMessageListProcessor(Object targetObject, Class<? extends Annotation> annotationType) {
-		this.delegate = new MessagingMethodInvokerHelper<T>(targetObject, annotationType, Object.class, true);
+		this.delegate = new MessagingMethodInvokerHelper(targetObject, annotationType, Object.class, true);
 	}
 
 	@Override
@@ -84,16 +85,9 @@ public class MethodInvokingMessageListProcessor<T> extends AbstractExpressionEva
 		return this.delegate.toString();
 	}
 
+	@SuppressWarnings("unchecked")
 	public T process(Collection<Message<?>> messages, Map<String, Object> aggregateHeaders) {
-		try {
-			return this.delegate.process(messages, aggregateHeaders);
-		}
-		catch (RuntimeException e) {
-			throw e;
-		}
-		catch (Exception e) {
-			throw new IllegalStateException("Failed to process message list", e);
-		}
+		return (T) this.delegate.process(messages, aggregateHeaders);
 	}
 
 	@Override

spring-integration-core/src/main/java/org/springframework/integration/channel/AbstractExecutorChannel.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2018 the original author or authors.
+ * Copyright 2015-2019 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.
@@ -46,20 +46,23 @@ import org.springframework.util.CollectionUtils;
  *
  * @author Artem Bilan
  * @author Gary Russell
+ *
+ * @since 4.2
+ *
  * @see ExecutorChannel
  * @see PublishSubscribeChannel
- * @since 4.2
+ *
  */
 public abstract class AbstractExecutorChannel extends AbstractSubscribableChannel
 		implements ExecutorChannelInterceptorAware {
 
-	protected volatile Executor executor;
+	protected volatile Executor executor; // NOSONAR
 
-	protected volatile AbstractDispatcher dispatcher;
+	protected volatile AbstractDispatcher dispatcher; // NOSONAR
 
-	protected volatile Integer maxSubscribers;
+	protected volatile Integer maxSubscribers; // NOSONAR
 
-	protected volatile int executorInterceptorsSize;
+	protected volatile int executorInterceptorsSize; // NOSONAR
 
 	public AbstractExecutorChannel(@Nullable Executor executor) {
 		this.executor = executor;
@@ -68,7 +71,6 @@ public abstract class AbstractExecutorChannel extends AbstractSubscribableChanne
 	/**
 	 * Specify the maximum number of subscribers supported by the
 	 * channel's dispatcher.
-	 *
 	 * @param maxSubscribers The maximum number of subscribers allowed.
 	 */
 	public void setMaxSubscribers(int maxSubscribers) {
@@ -112,6 +114,7 @@ public abstract class AbstractExecutorChannel extends AbstractSubscribableChanne
 	}
 
 	@Override
+	@Nullable
 	public ChannelInterceptor removeInterceptor(int index) {
 		ChannelInterceptor interceptor = super.removeInterceptor(index);
 		if (interceptor instanceof ExecutorChannelInterceptor) {
@@ -141,7 +144,7 @@ public abstract class AbstractExecutorChannel extends AbstractSubscribableChanne
 			Deque<ExecutorChannelInterceptor> interceptorStack = null;
 			try {
 				if (AbstractExecutorChannel.this.executorInterceptorsSize > 0) {
-					interceptorStack = new ArrayDeque<ExecutorChannelInterceptor>();
+					interceptorStack = new ArrayDeque<>();
 					message = applyBeforeHandle(message, interceptorStack);
 					if (message == null) {
 						return;
@@ -156,7 +159,7 @@ public abstract class AbstractExecutorChannel extends AbstractSubscribableChanne
 				if (!CollectionUtils.isEmpty(interceptorStack)) {
 					triggerAfterMessageHandled(message, ex, interceptorStack);
 				}
-				if (ex instanceof MessagingException) {
+				if (ex instanceof MessagingException) { // NOSONAR
 					throw new MessagingExceptionWrapper(message, (MessagingException) ex);
 				}
 				String description = "Failed to handle " + message + " to " + this + " in " + messageHandler;

spring-integration-core/src/main/java/org/springframework/integration/channel/AbstractMessageChannel.java

@@ -28,6 +28,7 @@ import java.util.concurrent.CopyOnWriteArrayList;
 
 import org.apache.commons.logging.Log;
 
+import org.springframework.beans.factory.BeanFactory;
 import org.springframework.core.OrderComparator;
 import org.springframework.integration.context.IntegrationContextUtils;
 import org.springframework.integration.context.IntegrationObjectSupport;
@@ -71,7 +72,7 @@ public abstract class AbstractMessageChannel extends IntegrationObjectSupport
 		implements MessageChannel, TrackableComponent, ChannelInterceptorAware, MessageChannelMetrics,
 		ConfigurableMetricsAware<AbstractMessageChannelMetrics> {
 
-	protected final ChannelInterceptorList interceptors;
+	protected final ChannelInterceptorList interceptors; // NOSONAR
 
 	private final Comparator<Object> orderComparator = new OrderComparator();
 
@@ -120,6 +121,7 @@ public abstract class AbstractMessageChannel extends IntegrationObjectSupport
 		this.metricsCaptor = metricsCaptor;
 	}
 
+	@Nullable
 	protected MetricsCaptor getMetricsCaptor() {
 		return this.metricsCaptor;
 	}
@@ -356,19 +358,20 @@ public abstract class AbstractMessageChannel extends IntegrationObjectSupport
 	protected void onInit() {
 		super.onInit();
 		if (this.messageConverter == null) {
-			if (getBeanFactory() != null) {
-				if (getBeanFactory().containsBean(
-						IntegrationContextUtils.INTEGRATION_DATATYPE_CHANNEL_MESSAGE_CONVERTER_BEAN_NAME)) {
-					this.messageConverter = this.getBeanFactory().getBean(
-							IntegrationContextUtils.INTEGRATION_DATATYPE_CHANNEL_MESSAGE_CONVERTER_BEAN_NAME,
-							MessageConverter.class);
-				}
+			BeanFactory beanFactory = getBeanFactory();
+			if (beanFactory != null &&
+					beanFactory.containsBean(
+							IntegrationContextUtils.INTEGRATION_DATATYPE_CHANNEL_MESSAGE_CONVERTER_BEAN_NAME)) {
+
+				this.messageConverter =
+						beanFactory.getBean(
+								IntegrationContextUtils.INTEGRATION_DATATYPE_CHANNEL_MESSAGE_CONVERTER_BEAN_NAME,
+								MessageConverter.class);
 			}
 		}
 		if (this.statsEnabled) {
 			this.channelMetrics.setFullStatsEnabled(true);
 		}
-
 		this.fullChannelName = null;
 	}
 
@@ -420,7 +423,7 @@ public abstract class AbstractMessageChannel extends IntegrationObjectSupport
 		Assert.notNull(messageArg.getPayload(), "message payload must not be null");
 		Message<?> message = messageArg;
 		if (this.shouldTrack) {
-			message = MessageHistory.write(message, this, this.getMessageBuilderFactory());
+			message = MessageHistory.write(message, this, getMessageBuilderFactory());
 		}
 
 		Deque<ChannelInterceptor> interceptorStack = null;
@@ -432,9 +435,7 @@ public abstract class AbstractMessageChannel extends IntegrationObjectSupport
 		AbstractMessageChannelMetrics metrics = this.channelMetrics;
 		SampleFacade sample = null;
 		try {
-			if (this.datatypes.length > 0) {
-				message = this.convertPayloadIfNecessary(message);
-			}
+			message = convertPayloadIfNecessary(message);
 			boolean debugEnabled = this.loggingEnabled && logger.isDebugEnabled();
 			if (debugEnabled) {
 				logger.debug("preSend on channel '" + this + "', message: " + message);
@@ -471,18 +472,18 @@ public abstract class AbstractMessageChannel extends IntegrationObjectSupport
 			}
 			return sent;
 		}
-		catch (Exception e) {
+		catch (Exception ex) {
 			if (countsAreEnabled && !metricsProcessed) {
 				if (sample != null) {
-					sample.stop(buildSendTimer(false, e.getClass().getSimpleName()));
+					sample.stop(buildSendTimer(false, ex.getClass().getSimpleName()));
 				}
 				metrics.afterSend(metricsContext, false);
 			}
 			if (interceptorStack != null) {
-				interceptorList.afterSendCompletion(message, this, sent, e, interceptorStack);
+				interceptorList.afterSendCompletion(message, this, sent, ex, interceptorStack);
 			}
 			throw IntegrationUtils.wrapInDeliveryExceptionIfNecessary(message,
-					() -> "failed to send Message to channel '" + this.getComponentName() + "'", e);
+					() -> "failed to send Message to channel '" + this.getComponentName() + "'", ex);
 		}
 	}
 
@@ -514,33 +515,38 @@ public abstract class AbstractMessageChannel extends IntegrationObjectSupport
 	}
 
 	private Message<?> convertPayloadIfNecessary(Message<?> message) {
-		// first pass checks if the payload type already matches any of the datatypes
-		for (Class<?> datatype : this.datatypes) {
-			if (datatype.isAssignableFrom(message.getPayload().getClass())) {
-				return message;
-			}
-		}
-		if (this.messageConverter != null) {
-			// second pass applies conversion if possible, attempting datatypes in order
+		if (this.datatypes.length > 0) {
+			// first pass checks if the payload type already matches any of the datatypes
 			for (Class<?> datatype : this.datatypes) {
-				Object converted = this.messageConverter.fromMessage(message, datatype);
-				if (converted != null) {
-					if (converted instanceof Message) {
-						return (Message<?>) converted;
-					}
-					else {
-						return getMessageBuilderFactory()
-								.withPayload(converted)
-								.copyHeaders(message.getHeaders())
-								.build();
+				if (datatype.isAssignableFrom(message.getPayload().getClass())) {
+					return message;
+				}
+			}
+			if (this.messageConverter != null) {
+				// second pass applies conversion if possible, attempting datatypes in order
+				for (Class<?> datatype : this.datatypes) {
+					Object converted = this.messageConverter.fromMessage(message, datatype);
+					if (converted != null) {
+						if (converted instanceof Message) {
+							return (Message<?>) converted;
+						}
+						else {
+							return getMessageBuilderFactory()
+									.withPayload(converted)
+									.copyHeaders(message.getHeaders())
+									.build();
+						}
 					}
 				}
 			}
+			throw new MessageDeliveryException(message, "Channel '" + this.getComponentName() +
+					"' expected one of the following data types [" +
+					StringUtils.arrayToCommaDelimitedString(this.datatypes) +
+					"], but received [" + message.getPayload().getClass() + "]");
+		}
+		else {
+			return message;
 		}
-		throw new MessageDeliveryException(message, "Channel '" + this.getComponentName() +
-				"' expected one of the following datataypes [" +
-				StringUtils.arrayToCommaDelimitedString(this.datatypes) +
-				"], but received [" + message.getPayload().getClass() + "]");
 	}
 
 	/**
@@ -556,7 +562,7 @@ public abstract class AbstractMessageChannel extends IntegrationObjectSupport
 	protected abstract boolean doSend(Message<?> message, long timeout);
 
 	@Override
-	public void destroy() throws Exception { // NOSONAR TODO: remove throws in 5.2
+	public void destroy() {
 		this.meters.forEach(MeterFacade::remove);
 		this.meters.clear();
 	}
@@ -566,9 +572,9 @@ public abstract class AbstractMessageChannel extends IntegrationObjectSupport
 	 */
 	protected static class ChannelInterceptorList {
 
-		private final Log logger;
+		protected final List<ChannelInterceptor> interceptors = new CopyOnWriteArrayList<>(); // NOSONAR
 
-		protected final List<ChannelInterceptor> interceptors = new CopyOnWriteArrayList<ChannelInterceptor>();
+		private final Log logger;
 
 		private int size;
 
@@ -671,15 +677,17 @@ public abstract class AbstractMessageChannel extends IntegrationObjectSupport
 		}
 
 		public void afterReceiveCompletion(@Nullable Message<?> message, MessageChannel channel,
-				@Nullable Exception ex, Deque<ChannelInterceptor> interceptorStack) {
+				@Nullable Exception ex, @Nullable Deque<ChannelInterceptor> interceptorStack) {
 
-			for (Iterator<ChannelInterceptor> iterator = interceptorStack.descendingIterator(); iterator.hasNext(); ) {
-				ChannelInterceptor interceptor = iterator.next();
-				try {
-					interceptor.afterReceiveCompletion(message, channel, ex);
-				}
-				catch (Exception ex2) {
-					this.logger.error("Exception from afterReceiveCompletion in " + interceptor, ex2);
+			if (interceptorStack != null) {
+				for (Iterator<ChannelInterceptor> iterator = interceptorStack.descendingIterator(); iterator.hasNext(); ) {
+					ChannelInterceptor interceptor = iterator.next();
+					try {
+						interceptor.afterReceiveCompletion(message, channel, ex);
+					}
+					catch (Exception ex2) {
+						this.logger.error("Exception from afterReceiveCompletion in " + interceptor, ex2);
+					}
 				}
 			}
 		}

spring-integration-core/src/main/java/org/springframework/integration/channel/AbstractPollableChannel.java

@@ -22,6 +22,7 @@ import java.util.List;
 
 import org.springframework.integration.support.management.PollableChannelManagement;
 import org.springframework.integration.support.management.metrics.CounterFacade;
+import org.springframework.integration.support.management.metrics.MetricsCaptor;
 import org.springframework.lang.Nullable;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.PollableChannel;
@@ -115,60 +116,61 @@ public abstract class AbstractPollableChannel extends AbstractMessageChannel
 			}
 			else {
 				if (countsEnabled) {
-					if (getMetricsCaptor() != null) {
-						incrementReceiveCounter();
-					}
+					incrementReceiveCounter();
 					getMetrics().afterReceive();
 					counted = true;
 				}
 
 				if (isLoggingEnabled() && logger.isDebugEnabled()) {
-						logger.debug("postReceive on channel '" + this + "', message: " + message);
+					logger.debug("postReceive on channel '" + this + "', message: " + message);
 				}
 
 			}
 
-			if (interceptorStack != null) {
-				if (message != null) {
-					message = interceptorList.postReceive(message, this);
-				}
-				interceptorList.afterReceiveCompletion(message, this, null, interceptorStack);
+			if (interceptorStack != null && message != null) {
+				message = interceptorList.postReceive(message, this);
 			}
+			interceptorList.afterReceiveCompletion(message, this, null, interceptorStack);
 			return message;
 		}
-		catch (RuntimeException e) {
+		catch (RuntimeException ex) {
 			if (countsEnabled && !counted) {
-				if (getMetricsCaptor() != null) {
-					CounterFacade counter = getMetricsCaptor().counterBuilder(RECEIVE_COUNTER_NAME)
-							.tag("name", getComponentName() == null ? "unknown" : getComponentName())
-							.tag("type", "channel")
-							.tag("result", "failure")
-							.tag("exception", e.getClass().getSimpleName())
-							.description("Messages received")
-							.build();
-					this.meters.add(counter);
-					counter.increment();
-				}
-				getMetrics().afterError();
+				incrementReceiveErrorCounter(ex);
 			}
-			if (interceptorStack != null) {
-				interceptorList.afterReceiveCompletion(null, this, e, interceptorStack);
-			}
-			throw e;
+			interceptorList.afterReceiveCompletion(null, this, ex, interceptorStack);
+			throw ex;
 		}
 	}
 
 	private void incrementReceiveCounter() {
-		if (this.receiveCounter == null) {
-			this.receiveCounter = getMetricsCaptor().counterBuilder(RECEIVE_COUNTER_NAME)
-					.tag("name", getComponentName())
-					.tag("type", "channel")
-					.tag("result", "success")
-					.tag("exception", "none")
-					.description("Messages received")
-					.build();
+		MetricsCaptor metricsCaptor = getMetricsCaptor();
+		if (metricsCaptor != null) {
+			if (this.receiveCounter == null) {
+				this.receiveCounter = buildReceiveCounter(metricsCaptor, null);
+			}
+			this.receiveCounter.increment();
 		}
-		this.receiveCounter.increment();
+	}
+
+	private void incrementReceiveErrorCounter(Exception ex) {
+		MetricsCaptor metricsCaptor = getMetricsCaptor();
+		if (metricsCaptor != null) {
+			buildReceiveCounter(metricsCaptor, ex).increment();
+		}
+		getMetrics().afterError();
+	}
+
+	private CounterFacade buildReceiveCounter(MetricsCaptor metricsCaptor, @Nullable Exception ex) {
+		CounterFacade counterFacade = metricsCaptor
+				.counterBuilder(RECEIVE_COUNTER_NAME)
+				.tag("name", getComponentName() == null ? "unknown" : getComponentName())
+				.tag("type", "channel")
+				.tag("result", ex == null ? "success" : "failure")
+				.tag("exception", ex == null ? "none" : ex.getClass().getSimpleName())
+				.description("Messages received")
+				.build();
+		this.meters.add(counterFacade);
+		return counterFacade;
 	}
 
 	@Override
@@ -207,6 +209,7 @@ public abstract class AbstractPollableChannel extends AbstractMessageChannel
 	}
 
 	@Override
+	@Nullable
 	public ChannelInterceptor removeInterceptor(int index) {
 		ChannelInterceptor interceptor = super.removeInterceptor(index);
 		if (interceptor instanceof ExecutorChannelInterceptor) {
@@ -233,7 +236,7 @@ public abstract class AbstractPollableChannel extends AbstractMessageChannel
 	protected abstract Message<?> doReceive(long timeout);
 
 	@Override
-	public void destroy() throws Exception { // NOSONAR TODO: remove throws in 5.2
+	public void destroy() {
 		super.destroy();
 		if (this.receiveCounter != null) {
 			this.receiveCounter.remove();

spring-integration-core/src/main/java/org/springframework/integration/endpoint/MessageProducerSupport.java

@@ -16,7 +16,7 @@
 
 package org.springframework.integration.endpoint;
 
-import org.springframework.beans.factory.BeanInitializationException;
+import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.SmartInitializingSingleton;
 import org.springframework.core.AttributeAccessor;
 import org.springframework.integration.core.MessageProducer;
@@ -26,6 +26,7 @@ import org.springframework.integration.support.DefaultErrorMessageStrategy;
 import org.springframework.integration.support.ErrorMessageStrategy;
 import org.springframework.integration.support.ErrorMessageUtils;
 import org.springframework.integration.support.management.TrackableComponent;
+import org.springframework.lang.Nullable;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageChannel;
 import org.springframework.messaging.MessagingException;
@@ -48,15 +49,15 @@ public abstract class MessageProducerSupport extends AbstractEndpoint implements
 
 	private ErrorMessageStrategy errorMessageStrategy = new DefaultErrorMessageStrategy();
 
-	private volatile MessageChannel outputChannel;
+	private MessageChannel outputChannel;
 
-	private volatile String outputChannelName;
+	private String outputChannelName;
 
-	private volatile MessageChannel errorChannel;
+	private MessageChannel errorChannel;
 
-	private volatile String errorChannelName;
+	private String errorChannelName;
 
-	private volatile boolean shouldTrack = false;
+	private boolean shouldTrack = false;
 
 	protected MessageProducerSupport() {
 		this.setPhase(Integer.MAX_VALUE / 2);
@@ -81,13 +82,10 @@ public abstract class MessageProducerSupport extends AbstractEndpoint implements
 
 	@Override
 	public MessageChannel getOutputChannel() {
-		if (this.outputChannelName != null) {
-			synchronized (this) {
-				if (this.outputChannelName != null) {
-					this.outputChannel = getChannelResolver().resolveDestination(this.outputChannelName);
-					this.outputChannelName = null;
-				}
-			}
+		String channelName = this.outputChannelName;
+		if (channelName != null) {
+			this.outputChannel = getChannelResolver().resolveDestination(channelName);
+			this.outputChannelName = null;
 		}
 		return this.outputChannel;
 	}
@@ -114,14 +112,12 @@ public abstract class MessageProducerSupport extends AbstractEndpoint implements
 	 * @return the channel or null.
 	 * @since 4.3
 	 */
+	@Nullable
 	public MessageChannel getErrorChannel() {
-		if (this.errorChannelName != null) {
-			synchronized (this) {
-				if (this.errorChannelName != null) {
-					this.errorChannel = getChannelResolver().resolveDestination(this.errorChannelName);
-					this.errorChannelName = null;
-				}
-			}
+		String channelName = this.errorChannelName;
+		if (channelName != null) {
+			this.errorChannel = getChannelResolver().resolveDestination(channelName);
+			this.errorChannelName = null;
 		}
 		return this.errorChannel;
 	}
@@ -164,15 +160,10 @@ public abstract class MessageProducerSupport extends AbstractEndpoint implements
 
 	@Override
 	protected void onInit() {
-		try {
-			super.onInit();
-		}
-		catch (Exception e) {
-			throw new BeanInitializationException("Cannot initialize: " + this, e);
-		}
-
-		if (this.getBeanFactory() != null) {
-			this.messagingTemplate.setBeanFactory(this.getBeanFactory());
+		super.onInit();
+		BeanFactory beanFactory = getBeanFactory();
+		if (beanFactory != null) {
+			this.messagingTemplate.setBeanFactory(beanFactory);
 		}
 
 	}
@@ -199,14 +190,16 @@ public abstract class MessageProducerSupport extends AbstractEndpoint implements
 			throw new MessagingException("cannot send a null message");
 		}
 		if (this.shouldTrack) {
-			message = MessageHistory.write(message, this, this.getMessageBuilderFactory());
+			message = MessageHistory.write(message, this, getMessageBuilderFactory());
 		}
 		try {
-			this.messagingTemplate.send(getOutputChannel(), message);
+			MessageChannel messageChannel = getOutputChannel();
+			Assert.state(messageChannel != null, "The 'outputChannel' or `outputChannelName` must be configured");
+			this.messagingTemplate.send(messageChannel, message);
 		}
-		catch (RuntimeException e) {
-			if (!sendErrorMessageIfNecessary(message, e)) {
-				throw e;
+		catch (RuntimeException ex) {
+			if (!sendErrorMessageIfNecessary(message, ex)) {
+				throw ex;
 			}
 		}
 	}

spring-integration-core/src/main/java/org/springframework/integration/graph/IntegrationGraphServer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2018 the original author or authors.
+ * Copyright 2016-2019 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.
@@ -24,6 +24,7 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
+import java.util.Objects;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.function.Function;
 import java.util.stream.Collectors;
@@ -155,7 +156,7 @@ public class IntegrationGraphServer implements ApplicationContextAware, Applicat
 		if (implementationVersion == null) {
 			implementationVersion = "unknown - is Spring Integration running from the distribution jar?";
 		}
-		Map<String, Object> descriptor = new HashMap<String, Object>();
+		Map<String, Object> descriptor = new HashMap<>();
 		descriptor.put("provider", "spring-integration");
 		descriptor.put("providerVersion", implementationVersion);
 		descriptor.put("providerFormatVersion", GRAPH_VERSION);
@@ -351,61 +352,54 @@ public class IntegrationGraphServer implements ApplicationContextAware, Applicat
 		}
 
 		private MessageGatewayNode gatewayNode(String name, MessagingGatewaySupport gateway) {
-			MessageChannel gwErrorChannel = gateway.getErrorChannel();
-			String errorChannel = gwErrorChannel != null ? gwErrorChannel.toString() : null;
-			MessageChannel gwRequestChannel = gateway.getRequestChannel();
-			String requestChannel = gwRequestChannel != null ? gwRequestChannel.toString() : null;
-			return new MessageGatewayNode(this.nodeId.incrementAndGet(), name, gateway,
-					requestChannel, errorChannel);
+			String errorChannel = Objects.toString(gateway.getErrorChannel(), null);
+			String requestChannel = Objects.toString(gateway.getRequestChannel(), null);
+			return new MessageGatewayNode(this.nodeId.incrementAndGet(), name, gateway, requestChannel, errorChannel);
 		}
 
 		private MessageProducerNode producerNode(String name, MessageProducerSupport producer) {
-			String errorChannel = producer.getErrorChannel() != null ? producer.getErrorChannel().toString() : null;
-			String outputChannel = producer.getOutputChannel() != null ? producer.getOutputChannel().toString() : null;
+			String errorChannel = Objects.toString(producer.getErrorChannel(), null);
+			String outputChannel = Objects.toString(producer.getOutputChannel(), null);
 			return new MessageProducerNode(this.nodeId.incrementAndGet(), name, producer,
 					outputChannel, errorChannel);
 		}
 
 		private MessageSourceNode sourceNode(String name, SourcePollingChannelAdapter adapter) {
-			String errorChannel = adapter.getDefaultErrorChannel() != null
-					? adapter.getDefaultErrorChannel().toString() : null;
-			String outputChannel = adapter.getOutputChannel() != null ? adapter.getOutputChannel().toString() : null;
+			String errorChannel = Objects.toString(adapter.getDefaultErrorChannel(), null);
+			String outputChannel = Objects.toString(adapter.getOutputChannel(), null);
 			return new MessageSourceNode(this.nodeId.incrementAndGet(), name, adapter.getMessageSource(),
 					outputChannel, errorChannel);
 		}
 
 		private MessageHandlerNode handlerNode(String name, IntegrationConsumer consumer) {
-			MessageChannel outputChannel = consumer.getOutputChannel();
-			String outputChannelName = outputChannel == null ? null : outputChannel.toString();
+			String outputChannelName = Objects.toString(consumer.getOutputChannel(), null);
 			MessageHandler handler = consumer.getHandler();
 			if (handler instanceof CompositeMessageHandler) {
 				return compositeHandler(name, consumer, (CompositeMessageHandler) handler, outputChannelName, null,
-							false);
+						false);
 			}
 			else if (handler instanceof DiscardingMessageHandler) {
 				return discardingHandler(name, consumer, (DiscardingMessageHandler) handler, outputChannelName, null,
-							false);
+						false);
 			}
 			else if (handler instanceof MappingMessageRouterManagement) {
 				return routingHandler(name, consumer, handler, (MappingMessageRouterManagement) handler,
-							outputChannelName, null, false);
+						outputChannelName, null, false);
 			}
 			else if (handler instanceof RecipientListRouterManagement) {
 				return recipientListRoutingHandler(name, consumer, handler, (RecipientListRouterManagement) handler,
-							outputChannelName, null, false);
+						outputChannelName, null, false);
 			}
 			else {
-				String inputChannel = consumer.getInputChannel() != null ? consumer.getInputChannel().toString() : null;
+				String inputChannel = Objects.toString(consumer.getInputChannel(), null);
 				return new MessageHandlerNode(this.nodeId.incrementAndGet(), name, handler,
-							inputChannel, outputChannelName);
+						inputChannel, outputChannelName);
 			}
 		}
 
 		private MessageHandlerNode polledHandlerNode(String name, PollingConsumer consumer) {
-			MessageChannel outputChannel = consumer.getOutputChannel();
-			String outputChannelName = outputChannel == null ? null : outputChannel.toString();
-			String errorChannel = consumer.getDefaultErrorChannel() != null
-					? consumer.getDefaultErrorChannel().toString() : null;
+			String outputChannelName = Objects.toString(consumer.getOutputChannel(), null);
+			String errorChannel = Objects.toString(consumer.getDefaultErrorChannel(), null);
 			MessageHandler handler = consumer.getHandler();
 			if (handler instanceof CompositeMessageHandler) {
 				return compositeHandler(name, consumer, (CompositeMessageHandler) handler, outputChannelName,
@@ -424,7 +418,7 @@ public class IntegrationGraphServer implements ApplicationContextAware, Applicat
 							outputChannelName, errorChannel, true);
 			}
 			else {
-				String inputChannel = consumer.getInputChannel() != null ? consumer.getInputChannel().toString() : null;
+				String inputChannel = Objects.toString(consumer.getInputChannel(), null);
 				return new ErrorCapableMessageHandlerNode(this.nodeId.incrementAndGet(), name, handler,
 							inputChannel, outputChannelName, errorChannel);
 			}
@@ -444,7 +438,7 @@ public class IntegrationGraphServer implements ApplicationContextAware, Applicat
 											named.getComponentType()))
 							.collect(Collectors.toList());
 
-			String inputChannel = consumer.getInputChannel() != null ? consumer.getInputChannel().toString() : null;
+			String inputChannel = Objects.toString(consumer.getInputChannel(), null);
 			return polled
 					? new ErrorCapableCompositeMessageHandlerNode(this.nodeId.incrementAndGet(), name, handler,
 						inputChannel, output, errors, innerHandlers)
@@ -455,8 +449,8 @@ public class IntegrationGraphServer implements ApplicationContextAware, Applicat
 		private MessageHandlerNode discardingHandler(String name, IntegrationConsumer consumer,
 				DiscardingMessageHandler handler, String output, String errors, boolean polled) {
 
-			String discards = handler.getDiscardChannel() != null ? handler.getDiscardChannel().toString() : null;
-			String inputChannel = consumer.getInputChannel() != null ? consumer.getInputChannel().toString() : null;
+			String discards = Objects.toString(handler.getDiscardChannel(), null);
+			String inputChannel = Objects.toString(consumer.getInputChannel(), null);
 			return polled
 					? new ErrorCapableDiscardingMessageHandlerNode(this.nodeId.incrementAndGet(), name, handler,
 						inputChannel, output, discards, errors)
@@ -472,7 +466,7 @@ public class IntegrationGraphServer implements ApplicationContextAware, Applicat
 							router.getDynamicChannelNames().stream())
 							.collect(Collectors.toList());
 
-			String inputChannel = consumer.getInputChannel() != null ? consumer.getInputChannel().toString() : null;
+			String inputChannel = Objects.toString(consumer.getInputChannel(), null);
 			return polled
 					? new ErrorCapableRoutingNode(this.nodeId.incrementAndGet(), name, handler,
 						inputChannel, output, errors, routes)
@@ -490,7 +484,7 @@ public class IntegrationGraphServer implements ApplicationContextAware, Applicat
 							.map(recipient -> ((Recipient) recipient).getChannel().toString())
 							.collect(Collectors.toList());
 
-			String inputChannel = consumer.getInputChannel() != null ? consumer.getInputChannel().toString() : null;
+			String inputChannel = Objects.toString(consumer.getInputChannel(), null);
 			return polled
 					? new ErrorCapableRoutingNode(this.nodeId.incrementAndGet(), name, handler,
 						inputChannel, output, errors, routes)

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

@@ -338,7 +338,7 @@ public abstract class AbstractMessageHandler extends IntegrationObjectSupport
 	}
 
 	@Override
-	public void destroy() throws Exception {
+	public void destroy() {
 		this.timers.forEach(MeterFacade::remove);
 	}
 

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

@@ -33,6 +33,7 @@ import org.springframework.integration.core.MessageProducer;
 import org.springframework.integration.core.MessagingTemplate;
 import org.springframework.integration.routingslip.RoutingSlipRouteStrategy;
 import org.springframework.integration.support.AbstractIntegrationMessageBuilder;
+import org.springframework.integration.support.utils.IntegrationUtils;
 import org.springframework.lang.Nullable;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageChannel;
@@ -64,7 +65,7 @@ import reactor.core.publisher.Mono;
 public abstract class AbstractMessageProducingHandler extends AbstractMessageHandler
 		implements MessageProducer, HeaderPropagationAware {
 
-	protected final MessagingTemplate messagingTemplate = new MessagingTemplate();
+	protected final MessagingTemplate messagingTemplate = new MessagingTemplate(); // NOSONAR final
 
 	private boolean async;
 
@@ -209,8 +210,9 @@ public abstract class AbstractMessageProducingHandler extends AbstractMessageHan
 	@Override
 	@Nullable
 	public MessageChannel getOutputChannel() {
-		if (this.outputChannelName != null) {
-			this.outputChannel = getChannelResolver().resolveDestination(this.outputChannelName);
+		String channelName = this.outputChannelName;
+		if (channelName != null) {
+			this.outputChannel = getChannelResolver().resolveDestination(channelName);
 			this.outputChannelName = null;
 		}
 		return this.outputChannel;
@@ -272,12 +274,13 @@ public abstract class AbstractMessageProducingHandler extends AbstractMessageHan
 			Object replyChannel) {
 
 		if (this.async && (reply instanceof ListenableFuture<?> || reply instanceof Publisher<?>)) {
+			MessageChannel messageChannel = getOutputChannel();
 			if (reply instanceof ListenableFuture<?> ||
-					!(getOutputChannel() instanceof ReactiveStreamsSubscribableChannel)) {
-				asyncNonReactiveReply(requestMessage, requestHeaders, reply, replyChannel);
+					!(messageChannel instanceof ReactiveStreamsSubscribableChannel)) {
+				asyncNonReactiveReply(requestMessage, reply, replyChannel);
 			}
 			else {
-				((ReactiveStreamsSubscribableChannel) getOutputChannel())
+				((ReactiveStreamsSubscribableChannel) messageChannel)
 						.subscribeTo(
 								Flux.from((Publisher<?>) reply)
 										.map(result -> createOutputMessage(result, requestHeaders)));
@@ -307,8 +310,8 @@ public abstract class AbstractMessageProducingHandler extends AbstractMessageHan
 		return builder;
 	}
 
-	private void asyncNonReactiveReply(final Message<?> requestMessage, final MessageHeaders requestHeaders,
-			Object reply, Object replyChannel) {
+	private void asyncNonReactiveReply(Message<?> requestMessage, Object reply, Object replyChannel) {
+
 		ListenableFuture<?> future;
 		if (reply instanceof ListenableFuture<?>) {
 			future = (ListenableFuture<?>) reply;
@@ -322,35 +325,7 @@ public abstract class AbstractMessageProducingHandler extends AbstractMessageHan
 			future = settableListenableFuture;
 		}
 
-		Object theReplyChannel = replyChannel;
-		future.addCallback(new ListenableFutureCallback<Object>() {
-
-			@Override
-			public void onSuccess(Object result) {
-				Message<?> replyMessage = null;
-				try {
-					replyMessage = createOutputMessage(result, requestHeaders);
-					sendOutput(replyMessage, theReplyChannel, false);
-				}
-				catch (Exception e) {
-					Exception exceptionToLogAndSend = e;
-					if (!(e instanceof MessagingException)) {
-						exceptionToLogAndSend = new MessageHandlingException(requestMessage, e);
-						if (replyMessage != null) {
-							exceptionToLogAndSend = new MessagingException(replyMessage, exceptionToLogAndSend);
-						}
-					}
-					logger.error("Failed to send async reply: " + result.toString(), exceptionToLogAndSend);
-					onFailure(exceptionToLogAndSend);
-				}
-			}
-
-			@Override
-			public void onFailure(Throwable ex) {
-				sendErrorMessage(requestMessage, ex);
-			}
-
-		});
+		future.addCallback(new ReplyFutureCallback(requestMessage, replyChannel));
 	}
 
 	private Object getOutputChannelFromRoutingSlip(Object reply, Message<?> requestMessage, List<?> routingSlip,
@@ -458,7 +433,7 @@ public abstract class AbstractMessageProducingHandler extends AbstractMessageHan
 		return true;
 	}
 
-	protected void sendErrorMessage(final Message<?> requestMessage, Throwable ex) {
+	protected void sendErrorMessage(Message<?> requestMessage, Throwable ex) {
 		Object errorChannel = resolveErrorChannel(requestMessage.getHeaders());
 		Throwable result = ex;
 		if (!(ex instanceof MessagingException)) {
@@ -473,10 +448,8 @@ public abstract class AbstractMessageProducingHandler extends AbstractMessageHan
 				sendOutput(new ErrorMessage(result), errorChannel, true);
 			}
 			catch (Exception e) {
-				Exception exceptionToLog = e;
-				if (!(e instanceof MessagingException)) {
-					exceptionToLog = new MessageHandlingException(requestMessage, e);
-				}
+				Exception exceptionToLog =
+						IntegrationUtils.wrapInHandlingExceptionIfNecessary(requestMessage, () -> null,  e);
 				logger.error("Failed to send async reply", exceptionToLog);
 			}
 		}
@@ -495,4 +468,43 @@ public abstract class AbstractMessageProducingHandler extends AbstractMessageHan
 		return errorChannel;
 	}
 
+	private final class ReplyFutureCallback implements ListenableFutureCallback<Object> {
+
+		private final Message<?> requestMessage;
+
+		private final Object replyChannel;
+
+		ReplyFutureCallback(Message<?> requestMessage, Object replyChannel) {
+			this.requestMessage = requestMessage;
+			this.replyChannel = replyChannel;
+		}
+
+
+		@Override
+		public void onSuccess(Object result) {
+			Message<?> replyMessage = null;
+			try {
+				replyMessage = createOutputMessage(result, this.requestMessage.getHeaders());
+				sendOutput(replyMessage, this.replyChannel, false);
+			}
+			catch (Exception ex) {
+				Exception exceptionToLogAndSend = ex;
+				if (!(ex instanceof MessagingException)) { // NOSONAR
+					exceptionToLogAndSend = new MessageHandlingException(this.requestMessage, ex);
+					if (replyMessage != null) {
+						exceptionToLogAndSend = new MessagingException(replyMessage, exceptionToLogAndSend);
+					}
+				}
+				logger.error("Failed to send async reply: " + result.toString(), exceptionToLogAndSend);
+				onFailure(exceptionToLogAndSend);
+			}
+		}
+
+		@Override
+		public void onFailure(Throwable ex) {
+			sendErrorMessage(this.requestMessage, ex);
+		}
+
+	}
+
 }

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

@@ -44,22 +44,22 @@ import org.springframework.messaging.Message;
  */
 public class MethodInvokingMessageProcessor<T> extends AbstractMessageProcessor<T> implements Lifecycle {
 
-	private final MessagingMethodInvokerHelper<T> delegate;
+	private final MessagingMethodInvokerHelper delegate;
 
 	public MethodInvokingMessageProcessor(Object targetObject, Method method) {
-		this.delegate = new MessagingMethodInvokerHelper<T>(targetObject, method, false);
+		this.delegate = new MessagingMethodInvokerHelper(targetObject, method, false);
 	}
 
 	public MethodInvokingMessageProcessor(Object targetObject, String methodName) {
-		this.delegate = new MessagingMethodInvokerHelper<T>(targetObject, methodName, false);
+		this.delegate = new MessagingMethodInvokerHelper(targetObject, methodName, false);
 	}
 
 	public MethodInvokingMessageProcessor(Object targetObject, String methodName, boolean canProcessMessageList) {
-		this.delegate = new MessagingMethodInvokerHelper<T>(targetObject, methodName, canProcessMessageList);
+		this.delegate = new MessagingMethodInvokerHelper(targetObject, methodName, canProcessMessageList);
 	}
 
 	public MethodInvokingMessageProcessor(Object targetObject, Class<? extends Annotation> annotationType) {
-		this.delegate = new MessagingMethodInvokerHelper<T>(targetObject, annotationType, false);
+		this.delegate = new MessagingMethodInvokerHelper(targetObject, annotationType, false);
 	}
 
 	@Override
@@ -69,7 +69,7 @@ public class MethodInvokingMessageProcessor<T> extends AbstractMessageProcessor<
 	}
 
 	@Override
-	public void setBeanFactory(@Nullable BeanFactory beanFactory) {
+	public void setBeanFactory(BeanFactory beanFactory) {
 		super.setBeanFactory(beanFactory);
 		this.delegate.setBeanFactory(beanFactory);
 	}
@@ -102,14 +102,15 @@ public class MethodInvokingMessageProcessor<T> extends AbstractMessageProcessor<
 
 	@Override
 	@Nullable
+	@SuppressWarnings("unchecked")
 	public T processMessage(Message<?> message) {
 		try {
-			return this.delegate.process(message);
+			return (T) this.delegate.process(message);
 		}
-		catch (Exception e) {
+		catch (Exception ex) {
 			throw IntegrationUtils.wrapInHandlingExceptionIfNecessary(message,
-					() -> "error occurred during processing message in 'MethodInvokingMessageProcessor' [" + this + "]",
-					e);
+					() -> "error occurred during processing message in 'MethodInvokingMessageProcessor' [" + this +
+							"]", ex);
 		}
 	}
 

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

@@ -124,13 +124,13 @@ import org.springframework.util.StringUtils;
  *
  * @since 2.0
  */
-public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator implements Lifecycle {
+public class MessagingMethodInvokerHelper extends AbstractExpressionEvaluator implements Lifecycle {
 
 	private static final String CANDIDATE_METHODS = "CANDIDATE_METHODS";
 
 	private static final String CANDIDATE_MESSAGE_METHODS = "CANDIDATE_MESSAGE_METHODS";
 
-	private static final Log logger = LogFactory.getLog(MessagingMethodInvokerHelper.class);
+	private static final Log LOGGER = LogFactory.getLog(MessagingMethodInvokerHelper.class);
 
 	// Number of times to try an InvocableHandlerMethod before giving up in favor of an expression.
 	private static final int FAILED_ATTEMPTS_THRESHOLD = 100;
@@ -151,16 +151,12 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 
 	private static final Map<SpelCompilerMode, ExpressionParser> SPEL_COMPILERS = new HashMap<>();
 
-	private static final TypeDescriptor messageTypeDescriptor = TypeDescriptor.valueOf(Message.class);
+	private static final TypeDescriptor MESSAGE_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Message.class);
 
-	@SuppressWarnings("unused")
-	private static final Collection<Message<?>> dummyMessages = Collections.emptyList();
+	private static final TypeDescriptor MESSAGE_LIST_TYPE_DESCRIPTOR =
+			TypeDescriptor.collection(Collection.class, TypeDescriptor.valueOf(Message.class));
 
-	private static final TypeDescriptor messageListTypeDescriptor =
-			new TypeDescriptor(ReflectionUtils.findField(MessagingMethodInvokerHelper.class, // NOSONAR never null
-					"dummyMessages"));
-
-	private static final TypeDescriptor messageArrayTypeDescriptor = TypeDescriptor.valueOf(Message[].class);
+	private static final TypeDescriptor MESSAGE_ARRAY_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Message[].class);
 
 	static {
 		SPEL_COMPILERS.put(SpelCompilerMode.OFF, EXPRESSION_PARSER_OFF);
@@ -175,38 +171,38 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 
 	private final JsonObjectMapper<?, ?> jsonObjectMapper;
 
-	private volatile String displayString;
-
-	private volatile boolean requiresReply;
-
 	private final Map<Class<?>, HandlerMethod> handlerMethods;
 
 	private final Map<Class<?>, HandlerMethod> handlerMessageMethods;
 
 	private final List<Map<Class<?>, HandlerMethod>> handlerMethodsList;
 
-	private HandlerMethod handlerMethod;
-
 	private final TypeDescriptor expectedType;
 
 	private final boolean canProcessMessageList;
 
-	private Class<? extends Annotation> annotationType;
+	private HandlerMethod handlerMethod;
 
-	private volatile boolean initialized;
+	private Class<? extends Annotation> annotationType;
 
 	private String methodName;
 
 	private Method method;
 
-	private boolean useSpelInvoker;
-
 	private HandlerMethod defaultHandlerMethod;
 
 	private BeanExpressionResolver resolver = new StandardBeanExpressionResolver();
 
 	private BeanExpressionContext expressionContext;
 
+	private volatile String displayString;
+
+	private volatile boolean requiresReply;
+
+	private volatile boolean initialized;
+
+	private boolean useSpelInvoker;
+
 	public MessagingMethodInvokerHelper(Object targetObject, Method method, Class<?> expectedType,
 			boolean canProcessMessageList) {
 
@@ -309,13 +305,13 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 	}
 
 	@Nullable
-	public T process(Message<?> message) throws Exception {
+	public Object process(Message<?> message) {
 		ParametersWrapper parameters = new ParametersWrapper(message);
 		return processInternal(parameters);
 	}
 
 	@Nullable
-	public T process(Collection<Message<?>> messages, Map<String, Object> headers) throws Exception {
+	public Object process(Collection<Message<?>> messages, Map<String, Object> headers) {
 		ParametersWrapper parameters = new ParametersWrapper(messages, headers);
 		return processInternal(parameters);
 	}
@@ -431,7 +427,7 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 		this.displayString = sb.toString() + "]";
 	}
 
-	private void prepareEvaluationContext() throws Exception {
+	private void prepareEvaluationContext() {
 		StandardEvaluationContext context = getEvaluationContext(false);
 		Class<?> targetType = AopUtils.getTargetClass(this.targetObject);
 		if (this.method != null) {
@@ -450,8 +446,13 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 			context.registerMethodFilter(targetType, filter);
 		}
 		context.setVariable("target", this.targetObject);
-		context.registerFunction("requiredHeader", ParametersWrapper.class.getDeclaredMethod("getHeader",
-				Map.class, String.class));
+		try {
+			context.registerFunction("requiredHeader",
+					ParametersWrapper.class.getDeclaredMethod("getHeader", Map.class, String.class));
+		}
+		catch (NoSuchMethodException ex) {
+			throw new IllegalStateException(ex);
+		}
 	}
 
 	private boolean canReturnExpectedType(AnnotatedMethodFilter filter, Class<?> targetType,
@@ -469,9 +470,8 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 		return false;
 	}
 
-	@SuppressWarnings("unchecked")
 	@Nullable
-	private T processInternal(ParametersWrapper parameters) throws Exception {
+	private Object processInternal(ParametersWrapper parameters) {
 		if (!this.initialized) {
 			initialize();
 		}
@@ -485,7 +485,7 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 		}
 		Expression expression = candidate.expression;
 
-		T result;
+		Object result;
 		if (this.useSpelInvoker || candidate.spelOnly) {
 			result = invokeExpression(expression, parameters);
 		}
@@ -494,7 +494,7 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 		}
 
 		if (result != null && this.expectedType != null) {
-			return (T) getEvaluationContext(true)
+			return getEvaluationContext(true)
 					.getTypeConverter()
 					.convertValue(result, TypeDescriptor.forObject(result), this.expectedType);
 		}
@@ -520,11 +520,11 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 	}
 
 	@SuppressWarnings("deprecation")
-	private synchronized void initialize() throws Exception {
+	private synchronized void initialize() {
 		if (!this.initialized) {
 			BeanFactory beanFactory = getBeanFactory();
 			if (isProvidedMessageHandlerFactoryBean()) {
-				logger.info("Overriding default instance of MessageHandlerMethodFactory with provided one.");
+				LOGGER.info("Overriding default instance of MessageHandlerMethodFactory with provided one.");
 				this.messageHandlerMethodFactory =
 						beanFactory.getBean(IntegrationContextUtils.MESSAGE_HANDLER_FACTORY_BEAN_NAME,
 								MessageHandlerMethodFactory.class);
@@ -589,13 +589,19 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 		}
 		NullAwarePayloadArgumentResolver nullResolver = new NullAwarePayloadArgumentResolver(messageConverter);
 		PayloadExpressionArgumentResolver payloadExpressionArgumentResolver = new PayloadExpressionArgumentResolver();
-		payloadExpressionArgumentResolver.setBeanFactory(beanFactory);
+		if (beanFactory != null) {
+			payloadExpressionArgumentResolver.setBeanFactory(beanFactory);
+		}
 
 		PayloadsArgumentResolver payloadsArgumentResolver = new PayloadsArgumentResolver();
-		payloadsArgumentResolver.setBeanFactory(beanFactory);
+		if (beanFactory != null) {
+			payloadsArgumentResolver.setBeanFactory(beanFactory);
+		}
 
 		MapArgumentResolver mapArgumentResolver = new MapArgumentResolver();
-		mapArgumentResolver.setBeanFactory(beanFactory);
+		if (beanFactory != null) {
+			mapArgumentResolver.setBeanFactory(beanFactory);
+		}
 
 		List<HandlerMethodArgumentResolver> customArgumentResolvers = new LinkedList<>();
 		customArgumentResolvers.add(payloadExpressionArgumentResolver);
@@ -604,7 +610,9 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 
 		if (this.canProcessMessageList) {
 			CollectionArgumentResolver collectionArgumentResolver = new CollectionArgumentResolver(true);
-			collectionArgumentResolver.setBeanFactory(beanFactory);
+			if (beanFactory != null) {
+				collectionArgumentResolver.setBeanFactory(beanFactory);
+			}
 			customArgumentResolvers.add(collectionArgumentResolver);
 		}
 
@@ -614,67 +622,83 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 				.setCustomArgumentResolvers(customArgumentResolvers);
 	}
 
-	@SuppressWarnings("unchecked")
-	private T invokeHandlerMethod(HandlerMethod handlerMethod, ParametersWrapper parameters) throws Exception {
+	private Object invokeHandlerMethod(HandlerMethod handlerMethod, ParametersWrapper parameters) {
 		try {
-			return (T) handlerMethod.invoke(parameters);
+			return handlerMethod.invoke(parameters);
 		}
-		catch (MethodArgumentResolutionException | MessageConversionException | IllegalStateException e) {
-			if (e instanceof MessageConversionException) {
-				if (e.getCause() instanceof ConversionFailedException &&
-						!(e.getCause().getCause() instanceof ConverterNotFoundException)) {
-					throw e;
-				}
-			}
-			else if (e instanceof IllegalStateException) {
-				if (!(e.getCause() instanceof IllegalArgumentException) ||
-						!e.getStackTrace()[0].getClassName().equals(InvocableHandlerMethod.class.getName()) ||
-						(!"argument type mismatch".equals(e.getCause().getMessage()) &&
-								// JVM generates GeneratedMethodAccessor### after several calls with less error
-								// checking
-								!e.getCause().getMessage().startsWith("java.lang.ClassCastException@"))) {
-					throw e;
-				}
-			}
-
-			Expression expression = handlerMethod.expression;
-
-			if (++handlerMethod.failedAttempts >= FAILED_ATTEMPTS_THRESHOLD) {
-				handlerMethod.spelOnly = true;
-				if (logger.isInfoEnabled()) {
-					logger.info("Failed to invoke [ " + handlerMethod.invocableHandlerMethod +
-							"] with provided arguments [ " + parameters + " ]. \n" +
-							"Falling back to SpEL invocation for expression [ " +
-							expression.getExpressionString() + " ]");
-				}
-			}
-
-			return invokeExpression(expression, parameters);
+		catch (MethodArgumentResolutionException | MessageConversionException | IllegalStateException ex) {
+			return processInvokeExceptionAndFallbackToExpressionIfAny(handlerMethod, parameters, ex);
+		}
+		catch (RuntimeException ex) { // NOSONAR no way to handle conditional catch according Sonar rules
+			throw ex;
+		}
+		catch (Exception ex) {
+			throw new IllegalStateException("HandlerMethod invocation error", ex);
 		}
 	}
 
-	@SuppressWarnings("unchecked")
-	private T invokeExpression(Expression expression, ParametersWrapper parameters) throws Exception {
+	private Object processInvokeExceptionAndFallbackToExpressionIfAny(HandlerMethod handlerMethod,
+			ParametersWrapper parameters, RuntimeException ex) {
+
+		if (ex instanceof MessageConversionException) {
+			if (ex.getCause() instanceof ConversionFailedException &&
+					!(ex.getCause().getCause() instanceof ConverterNotFoundException)) {
+				throw ex;
+			}
+		}
+		else if (ex instanceof IllegalStateException && // NOSONAR complex boolean expression
+				(!(ex.getCause() instanceof IllegalArgumentException) ||
+				!ex.getStackTrace()[0].getClassName().equals(InvocableHandlerMethod.class.getName()) ||
+				(!"argument type mismatch".equals(ex.getCause().getMessage()) &&
+						// JVM generates GeneratedMethodAccessor### after several calls with less error
+						// checking
+						!ex.getCause().getMessage().startsWith("java.lang.ClassCastException@")))) {
+			throw ex;
+		}
+
+		return fallbackToInvokeExpression(handlerMethod, parameters);
+	}
+
+	private Object fallbackToInvokeExpression(HandlerMethod handlerMethod, ParametersWrapper parameters) {
+		Expression expression = handlerMethod.expression;
+
+		if (++handlerMethod.failedAttempts >= FAILED_ATTEMPTS_THRESHOLD) {
+			handlerMethod.spelOnly = true;
+			if (LOGGER.isInfoEnabled()) {
+				LOGGER.info("Failed to invoke [ " + handlerMethod.invocableHandlerMethod +
+						"] with provided arguments [ " + parameters + " ]. \n" +
+						"Falling back to SpEL invocation for expression [ " +
+						expression.getExpressionString() + " ]");
+			}
+		}
+
+		return invokeExpression(expression, parameters);
+	}
+
+	private Object invokeExpression(Expression expression, ParametersWrapper parameters) {
 		try {
 
 			convertJsonPayloadIfNecessary(parameters);
-			return (T) evaluateExpression(expression, parameters);
+			return evaluateExpression(expression, parameters);
 		}
-		catch (Exception e) {
-			Throwable evaluationException = e;
-			if ((e instanceof EvaluationException || e instanceof MessageHandlingException)
-					&& e.getCause() != null) {
-				evaluationException = e.getCause();
-			}
-			if (evaluationException instanceof Exception) {
-				throw (Exception) evaluationException;
-			}
-			else {
-				throw new IllegalStateException("Cannot process message", evaluationException);
-			}
+		catch (Exception ex) {
+			throw processEvaluationException(ex);
 		}
 	}
 
+	private RuntimeException processEvaluationException(Exception ex) {
+		Throwable evaluationException = ex;
+		if ((ex instanceof EvaluationException || ex instanceof MessageHandlingException)
+				&& ex.getCause() != null) {
+			evaluationException = ex.getCause();
+		}
+		if (evaluationException instanceof RuntimeException) {
+			return (RuntimeException) evaluationException;
+		}
+		return new IllegalStateException("Cannot process message", evaluationException);
+	}
+
+
 	/*
 	 * If there's a single method, it is SpEL only, the content is JSON,
 	 * the payload is a String or byte[], the parameter doesn't match the payload,
@@ -687,33 +711,36 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 				this.jsonObjectMapper != null) {
 
 			Class<?> type = this.handlerMethod.targetParameterType;
-			if ((parameters.getPayload() instanceof String && !type.equals(String.class)
+			if ((parameters.getPayload() instanceof String && !type.equals(String.class) // NOSONAR
 					|| parameters.getPayload() instanceof byte[] && !type.equals(byte[].class))
 					&& contentTypeIsJson(parameters.message)) {
 
-				try {
-					Object targetPayload = this.jsonObjectMapper.fromJson(parameters.getPayload(), type);
-
-					if (this.handlerMethod.targetParameterTypeDescriptor.isAssignableTo(messageTypeDescriptor)) {
-						parameters.message =
-								getMessageBuilderFactory()
-										.withPayload(targetPayload)
-										.copyHeaders(parameters.getHeaders())
-										.build();
-					}
-					else {
-						parameters.payload = targetPayload;
-					}
-
-
-				}
-				catch (Exception e) {
-					logger.debug("Failed to convert from JSON", e);
-				}
+				doConvertJsonPayload(parameters);
 			}
 		}
 	}
 
+	private void doConvertJsonPayload(ParametersWrapper parameters) {
+		try {
+			Object targetPayload =
+					this.jsonObjectMapper.fromJson(parameters.getPayload(), this.handlerMethod.targetParameterType);
+
+			if (this.handlerMethod.targetParameterTypeDescriptor.isAssignableTo(MESSAGE_TYPE_DESCRIPTOR)) {
+				parameters.message =
+						getMessageBuilderFactory()
+								.withPayload(targetPayload)
+								.copyHeaders(parameters.getHeaders())
+								.build();
+			}
+			else {
+				parameters.payload = targetPayload;
+			}
+		}
+		catch (Exception e) {
+			LOGGER.debug("Failed to convert from JSON", e);
+		}
+	}
+
 	private boolean contentTypeIsJson(Message<?> message) {
 		Object contentType = message.getHeaders().get(MessageHeaders.CONTENT_TYPE);
 		return contentType != null && contentType.toString().contains("json");
@@ -789,15 +816,15 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 				checkSpelInvokerRequired(targetClass, method1, handlerMethod1);
 			}
 			catch (IneligibleMethodException e) {
-				if (logger.isDebugEnabled()) {
-					logger.debug("Method [" + method1 + "] is not eligible for Message handling "
+				if (LOGGER.isDebugEnabled()) {
+					LOGGER.debug("Method [" + method1 + "] is not eligible for Message handling "
 							+ e.getMessage() + ".");
 				}
 				return;
 			}
 			catch (Exception e) {
-				if (logger.isDebugEnabled()) {
-					logger.debug("Method [" + method1 + "] is not eligible for Message handling.", e);
+				if (LOGGER.isDebugEnabled()) {
+					LOGGER.debug("Method [" + method1 + "] is not eligible for Message handling.", e);
 				}
 				return;
 			}
@@ -877,8 +904,8 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 				try {
 					if ("org.springframework.integration.gateway.RequestReplyExchanger".equals(iface.getName())) {
 						frameworkMethods.add(targetClass.getMethod("exchange", Message.class));
-						if (logger.isDebugEnabled()) {
-							logger.debug(targetObject.getClass() +
+						if (LOGGER.isDebugEnabled()) {
+							LOGGER.debug(targetObject.getClass() +
 									": Ambiguous fallback methods; using RequestReplyExchanger.exchange()");
 						}
 					}
@@ -996,8 +1023,9 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 	}
 
 	private String resolve(String value) {
-		if (getBeanFactory() != null && getBeanFactory() instanceof ConfigurableBeanFactory) {
-			return ((ConfigurableBeanFactory) getBeanFactory()).resolveEmbeddedValue(value);
+		BeanFactory beanFactory = getBeanFactory();
+		if (beanFactory instanceof ConfigurableBeanFactory) {
+			return ((ConfigurableBeanFactory) beanFactory).resolveEmbeddedValue(value);
 		}
 		return value;
 	}
@@ -1015,7 +1043,7 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 					}
 				}
 				catch (Exception e) {
-					logger.debug("Exception trying to extract interface", e);
+					LOGGER.debug("Exception trying to extract interface", e);
 				}
 			}
 		}
@@ -1066,7 +1094,7 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 	}
 
 	private static boolean isMethodDefinedOnObjectClass(Method method) {
-		return method != null &&
+		return method != null && // NOSONAR
 				(method.getDeclaringClass().equals(Object.class) || ReflectionUtils.isEqualsMethod(method) ||
 						ReflectionUtils.isHashCodeMethod(method) || ReflectionUtils.isToStringMethod(method) ||
 						AopUtils.isFinalizeMethod(method) || (method.getName().equals("clone")
@@ -1113,13 +1141,20 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 		}
 
 
-		@SuppressWarnings("unchecked")
-		public <T> T invoke(ParametersWrapper parameters) throws Exception {
+		public Object invoke(ParametersWrapper parameters) {
 			Message<?> message = parameters.getMessage();
 			if (this.canProcessMessageList) {
 				message = new MutableMessage<>(parameters.getMessages(), parameters.getHeaders());
 			}
-			return (T) this.invocableHandlerMethod.invoke(message);
+			try {
+				return this.invocableHandlerMethod.invoke(message);
+			}
+			catch (RuntimeException ex) { // NOSONAR no way to handle conditional catch according Sonar rules
+				throw ex;
+			}
+			catch (Exception ex) {
+				throw new IllegalStateException("InvocableHandlerMethod invoke error", ex);
+			}
 		}
 
 		Class<?> getTargetParameterType() {
@@ -1191,14 +1226,14 @@ public class MessagingMethodInvokerHelper<T> extends AbstractExpressionEvaluator
 						sb.append(this.determineHeaderExpression(mappingAnnotation, methodParameter));
 					}
 				}
-				else if (parameterTypeDescriptor.isAssignableTo(messageTypeDescriptor)) {
+				else if (parameterTypeDescriptor.isAssignableTo(MESSAGE_TYPE_DESCRIPTOR)) {
 					this.messageMethod = true;
 					sb.append("message");
 					this.setExclusiveTargetParameterType(parameterTypeDescriptor, methodParameter);
 				}
 				else if (this.canProcessMessageList &&
-						(parameterTypeDescriptor.isAssignableTo(messageListTypeDescriptor)
-								|| parameterTypeDescriptor.isAssignableTo(messageArrayTypeDescriptor))) {
+						(parameterTypeDescriptor.isAssignableTo(MESSAGE_LIST_TYPE_DESCRIPTOR)
+								|| parameterTypeDescriptor.isAssignableTo(MESSAGE_ARRAY_TYPE_DESCRIPTOR))) {
 					sb.append("messages");
 					this.setExclusiveTargetParameterType(parameterTypeDescriptor, methodParameter);
 				}

spring-integration-core/src/main/java/org/springframework/integration/support/AbstractIntegrationMessageBuilder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2018 the original author or authors.
+ * Copyright 2014-2019 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.
@@ -150,7 +150,7 @@ public abstract class AbstractIntegrationMessageBuilder<T> {
 	 * @see #copyHeadersIfAbsent(Map)
 	 */
 	public AbstractIntegrationMessageBuilder<T> filterAndCopyHeadersIfAbsent(Map<String, ?> headersToCopy,
-			String... headerPatternsToFilter) {
+			@Nullable String... headerPatternsToFilter) {
 
 		Map<String, ?> headers = headersToCopy;
 

spring-integration-core/src/main/java/org/springframework/integration/support/utils/IntegrationUtils.java

@@ -184,9 +184,11 @@ public final class IntegrationUtils {
 		RuntimeException runtimeException = (ex instanceof RuntimeException)
 				? (RuntimeException) ex
 				: new MessageHandlingException(message, text.get(), ex);
+
 		if (!(ex instanceof MessagingException) ||
 				((MessagingException) ex).getFailedMessage() == null) {
-			runtimeException = new MessageHandlingException(message, text.get(), ex);
+			runtimeException = new MessageHandlingException(message, text.get(),
+					(ex instanceof IllegalStateException && ex.getCause() != null) ? ex.getCause() : ex);
 		}
 		return runtimeException;
 	}

spring-integration-core/src/main/java/org/springframework/integration/util/AbstractExpressionEvaluator.java

@@ -47,7 +47,7 @@ import org.springframework.messaging.Message;
  */
 public abstract class AbstractExpressionEvaluator implements BeanFactoryAware, InitializingBean {
 
-	protected final Log logger = LogFactory.getLog(this.getClass());
+	protected final Log logger = LogFactory.getLog(this.getClass()); // NOSONAR final
 
 	protected static final ExpressionParser EXPRESSION_PARSER = new SpelExpressionParser();
 
@@ -131,7 +131,7 @@ public abstract class AbstractExpressionEvaluator implements BeanFactoryAware, I
 		catch (Exception ex) {
 			this.logger.debug("SpEL Expression evaluation failed with Exception.", ex);
 			Throwable cause = null;
-			if (ex instanceof EvaluationException) {
+			if (ex instanceof EvaluationException) { // NOSONAR
 				cause = ex.getCause();
 			}
 			throw IntegrationUtils.wrapInHandlingExceptionIfNecessary(message,

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

@@ -237,14 +237,13 @@ public class AggregatorParserTests {
 	}
 
 	@Test
-	@SuppressWarnings("unchecked")
 	public void testAggregatorWithPojoReleaseStrategy() {
 		MessageChannel input = this.context.getBean("aggregatorWithPojoReleaseStrategyInput", MessageChannel.class);
 		EventDrivenConsumer endpoint = this.context.getBean("aggregatorWithPojoReleaseStrategy", EventDrivenConsumer.class);
 		ReleaseStrategy releaseStrategy =
 				TestUtils.getPropertyValue(endpoint, "handler.releaseStrategy", ReleaseStrategy.class);
 		assertThat(releaseStrategy instanceof MethodInvokingReleaseStrategy).isTrue();
-		MessagingMethodInvokerHelper<Long> methodInvokerHelper =
+		MessagingMethodInvokerHelper methodInvokerHelper =
 				TestUtils.getPropertyValue(releaseStrategy, "adapter.delegate", MessagingMethodInvokerHelper.class);
 		Object handlerMethods = TestUtils.getPropertyValue(methodInvokerHelper, "handlerMethods");
 		assertThat(handlerMethods).isNull();

spring-integration-core/src/test/java/org/springframework/integration/handler/MethodInvokingMessageProcessorTests.java

@@ -446,7 +446,7 @@ public class MethodInvokingMessageProcessorTests {
 		processor.setBeanFactory(mock(BeanFactory.class));
 		assertThatExceptionOfType(MessageHandlingException.class)
 				.isThrownBy(() -> processor.processMessage(new GenericMessage<>("foo")))
-				.withCauseInstanceOf(CheckedException.class);
+				.withRootCauseInstanceOf(CheckedException.class);
 	}
 
 	@Test
@@ -896,8 +896,7 @@ public class MethodInvokingMessageProcessorTests {
 			processor.processMessage(new GenericMessage<>("foo"));
 		}
 		catch (Exception e) {
-			assertThat(e.getCause()).isInstanceOf(IllegalStateException.class);
-			assertThat(e.getCause().getCause()).isInstanceOf(IllegalArgumentException.class);
+			assertThat(e.getCause()).isInstanceOf(IllegalArgumentException.class);
 			assertThat(e.getCause().getStackTrace()[0].getClassName()).isEqualTo(A.class.getName());
 		}
 
@@ -976,8 +975,8 @@ public class MethodInvokingMessageProcessorTests {
 	@Test
 	public void testUseSpelInvoker() throws Exception {
 		UseSpelInvokerBean bean = new UseSpelInvokerBean();
-		MessagingMethodInvokerHelper<?> helper =
-				new MessagingMethodInvokerHelper<>(bean,
+		MessagingMethodInvokerHelper helper =
+				new MessagingMethodInvokerHelper(bean,
 						UseSpelInvokerBean.class.getDeclaredMethod("foo", String.class), false);
 		helper.setBeanFactory(mock(BeanFactory.class));
 		Message<?> message = new GenericMessage<>("Test");
@@ -985,28 +984,28 @@ public class MethodInvokingMessageProcessorTests {
 		assertThat(TestUtils.getPropertyValue(helper, "handlerMethod.expression.configuration.compilerMode"))
 				.isEqualTo(SpelCompilerMode.OFF);
 
-		helper = new MessagingMethodInvokerHelper<>(bean,
+		helper = new MessagingMethodInvokerHelper(bean,
 				UseSpelInvokerBean.class.getDeclaredMethod("bar", String.class), false);
 		helper.setBeanFactory(mock(BeanFactory.class));
 		helper.process(message);
 		assertThat(TestUtils.getPropertyValue(helper, "handlerMethod.expression.configuration.compilerMode"))
 				.isEqualTo(SpelCompilerMode.IMMEDIATE);
 
-		helper = new MessagingMethodInvokerHelper<>(bean,
+		helper = new MessagingMethodInvokerHelper(bean,
 				UseSpelInvokerBean.class.getDeclaredMethod("baz", String.class), false);
 		helper.setBeanFactory(mock(BeanFactory.class));
 		helper.process(message);
 		assertThat(TestUtils.getPropertyValue(helper, "handlerMethod.expression.configuration.compilerMode"))
 				.isEqualTo(SpelCompilerMode.MIXED);
 
-		helper = new MessagingMethodInvokerHelper<>(bean,
+		helper = new MessagingMethodInvokerHelper(bean,
 				UseSpelInvokerBean.class.getDeclaredMethod("qux", String.class), false);
 		helper.setBeanFactory(mock(BeanFactory.class));
 		helper.process(message);
 		assertThat(TestUtils.getPropertyValue(helper, "handlerMethod.expression.configuration.compilerMode"))
 				.isEqualTo(SpelCompilerMode.OFF);
 
-		helper = new MessagingMethodInvokerHelper<>(bean,
+		helper = new MessagingMethodInvokerHelper(bean,
 				UseSpelInvokerBean.class.getDeclaredMethod("fiz", String.class), false);
 		helper.setBeanFactory(mock(BeanFactory.class));
 		try {
@@ -1017,7 +1016,7 @@ public class MethodInvokingMessageProcessorTests {
 					.isEqualTo("No enum constant org.springframework.expression.spel.SpelCompilerMode.JUNK");
 		}
 
-		helper = new MessagingMethodInvokerHelper<>(bean,
+		helper = new MessagingMethodInvokerHelper(bean,
 				UseSpelInvokerBean.class.getDeclaredMethod("buz", String.class), false);
 		ConfigurableListableBeanFactory bf = mock(ConfigurableListableBeanFactory.class);
 		willAnswer(returnsFirstArg()).given(bf).resolveEmbeddedValue(anyString());
@@ -1031,13 +1030,13 @@ public class MethodInvokingMessageProcessorTests {
 		}
 
 		// Check other CTORs
-		helper = new MessagingMethodInvokerHelper<>(bean, "bar", false);
+		helper = new MessagingMethodInvokerHelper(bean, "bar", false);
 		helper.setBeanFactory(mock(BeanFactory.class));
 		helper.process(message);
 		assertThat(TestUtils.getPropertyValue(helper, "handlerMethod.expression.configuration.compilerMode"))
 				.isEqualTo(SpelCompilerMode.IMMEDIATE);
 
-		helper = new MessagingMethodInvokerHelper<>(bean, ServiceActivator.class, false);
+		helper = new MessagingMethodInvokerHelper(bean, ServiceActivator.class, false);
 		helper.setBeanFactory(mock(BeanFactory.class));
 		helper.process(message);
 		assertThat(TestUtils.getPropertyValue(helper, "handlerMethod.expression.configuration.compilerMode"))
@@ -1047,8 +1046,8 @@ public class MethodInvokingMessageProcessorTests {
 	@Test
 	public void testSingleMethodJson() throws Exception {
 		SingleMethodJsonWithSpELBean bean = new SingleMethodJsonWithSpELBean();
-		MessagingMethodInvokerHelper<?> helper =
-				new MessagingMethodInvokerHelper<>(bean,
+		MessagingMethodInvokerHelper helper =
+				new MessagingMethodInvokerHelper(bean,
 						SingleMethodJsonWithSpELBean.class.getDeclaredMethod("foo",
 								SingleMethodJsonWithSpELBean.Foo.class),
 						false);
@@ -1063,7 +1062,7 @@ public class MethodInvokingMessageProcessorTests {
 	@Test
 	public void testSingleMethodBadJson() throws Exception {
 		SingleMethodJsonWithSpELMessageWildBean bean = new SingleMethodJsonWithSpELMessageWildBean();
-		MessagingMethodInvokerHelper<?> helper = new MessagingMethodInvokerHelper<>(bean,
+		MessagingMethodInvokerHelper helper = new MessagingMethodInvokerHelper(bean,
 				SingleMethodJsonWithSpELMessageWildBean.class.getDeclaredMethod("foo", Message.class), false);
 		helper.setBeanFactory(mock(BeanFactory.class));
 		Message<?> message = new GenericMessage<>("baz",
@@ -1075,7 +1074,7 @@ public class MethodInvokingMessageProcessorTests {
 	@Test
 	public void testSingleMethodJsonMessageFoo() throws Exception {
 		SingleMethodJsonWithSpELMessageFooBean bean = new SingleMethodJsonWithSpELMessageFooBean();
-		MessagingMethodInvokerHelper<?> helper = new MessagingMethodInvokerHelper<>(bean,
+		MessagingMethodInvokerHelper helper = new MessagingMethodInvokerHelper(bean,
 				SingleMethodJsonWithSpELMessageFooBean.class.getDeclaredMethod("foo", Message.class), false);
 		helper.setBeanFactory(mock(BeanFactory.class));
 
@@ -1088,7 +1087,7 @@ public class MethodInvokingMessageProcessorTests {
 	@Test
 	public void testSingleMethodJsonMessageWild() throws Exception {
 		SingleMethodJsonWithSpELMessageWildBean bean = new SingleMethodJsonWithSpELMessageWildBean();
-		MessagingMethodInvokerHelper<?> helper = new MessagingMethodInvokerHelper<>(bean,
+		MessagingMethodInvokerHelper helper = new MessagingMethodInvokerHelper(bean,
 				SingleMethodJsonWithSpELMessageWildBean.class.getDeclaredMethod("foo", Message.class), false);
 		helper.setBeanFactory(mock(BeanFactory.class));
 

spring-integration-core/src/test/java/org/springframework/integration/resource/ResourceInboundChannelAdapterParserTests.java

@@ -27,7 +27,6 @@ import org.junit.BeforeClass;
 import org.junit.Test;
 
 import org.springframework.beans.factory.BeanCreationException;
-import org.springframework.context.ApplicationContext;
 import org.springframework.context.support.ClassPathXmlApplicationContext;
 import org.springframework.core.io.Resource;
 import org.springframework.integration.channel.QueueChannel;
@@ -69,8 +68,8 @@ public class ResourceInboundChannelAdapterParserTests {
 
 	@Test
 	public void testDefaultConfig() {
-		ApplicationContext context = new ClassPathXmlApplicationContext("ResourcePatternResolver-config.xml",
-				this.getClass());
+		ClassPathXmlApplicationContext context =
+				new ClassPathXmlApplicationContext("ResourcePatternResolver-config.xml", getClass());
 		SourcePollingChannelAdapter resourceAdapter = context.getBean("resourceAdapterDefault",
 				SourcePollingChannelAdapter.class);
 		ResourceRetrievingMessageSource source = TestUtils.getPropertyValue(resourceAdapter, "source",
@@ -81,17 +80,18 @@ public class ResourceInboundChannelAdapterParserTests {
 
 		assertThat(TestUtils.getPropertyValue(source, "pattern")).isEqualTo("/**/*");
 		assertThat(TestUtils.getPropertyValue(source, "patternResolver")).isEqualTo(context);
+		context.close();
 	}
 
 	@Test(expected = BeanCreationException.class)
 	public void testDefaultConfigNoLocationPattern() {
-		new ClassPathXmlApplicationContext("ResourcePatternResolver-config-fail.xml", this.getClass()).close();
+		new ClassPathXmlApplicationContext("ResourcePatternResolver-config-fail.xml", getClass()).close();
 	}
 
 	@Test
 	public void testCustomPatternResolver() {
-		ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
-				"ResourcePatternResolver-config-custom.xml", this.getClass());
+		ClassPathXmlApplicationContext context =
+				new ClassPathXmlApplicationContext("ResourcePatternResolver-config-custom.xml", getClass());
 		SourcePollingChannelAdapter resourceAdapter = context.getBean("resourceAdapterDefault",
 				SourcePollingChannelAdapter.class);
 		ResourceRetrievingMessageSource source = TestUtils.getPropertyValue(resourceAdapter, "source",