Sonar fixes

* exposing internal objects
* boolean complexity
* names, methods with _
* missing `default` in switch
* lost stack trace
* unnecessary null check before instanceof
* unused parameter

* Fix method name

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

@@ -65,7 +65,7 @@ public class MessageGroupExpiredEvent extends IntegrationEvent {
 	}
 
 	public Date getExpired() {
-		return this.expired;
+		return (Date) this.expired.clone();
 	}
 
 	public boolean isDiscarded() {

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

@@ -66,7 +66,7 @@ public class GlobalChannelInterceptorWrapper implements Ordered {
 	}
 
 	public String[] getPatterns() {
-		return this.patterns;
+		return this.patterns; // NOSONAR - expose internals
 	}
 
 	@Override

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

@@ -132,9 +132,13 @@ public class FilterFactoryBean extends AbstractStandardMessageHandlerFactoryBean
 	@Override
 	protected boolean canBeUsedDirect(AbstractMessageProducingHandler handler) {
 		return handler instanceof MessageFilter
-				|| (!(handler instanceof MessageSelector)
-				&& this.discardChannel == null && this.throwExceptionOnRejection == null
-				&& this.discardWithinAdvice == null);
+				|| (!(handler instanceof MessageSelector) && noFilterAttributesProvided());
+	}
+
+	private boolean noFilterAttributesProvided() {
+		return this.discardChannel == null
+				&& this.throwExceptionOnRejection == null
+				&& this.discardWithinAdvice == null;
 	}
 
 	@Override

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

@@ -152,7 +152,7 @@ public class RouterFactoryBean extends AbstractStandardMessageHandlerFactoryBean
 	}
 
 	protected boolean noRouterAttributesProvided() {
-		return this.channelMappings == null && this.defaultOutputChannel == null
+		return this.channelMappings == null && this.defaultOutputChannel == null // NOSONAR boolean complexity
 				&& getSendTimeout() == null && this.resolutionRequired == null && this.applySequence == null
 				&& this.ignoreSendFailures == null;
 	}

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

@@ -395,9 +395,12 @@ public abstract class AbstractMethodAnnotationPostProcessor<T extends Annotation
 			String receiveTimeout = this.beanFactory.resolveEmbeddedValue(poller.receiveTimeout());
 
 			if (StringUtils.hasText(ref)) {
-				Assert.state(!StringUtils.hasText(triggerRef) && !StringUtils.hasText(executorRef) &&
-								!StringUtils.hasText(cron) && !StringUtils.hasText(fixedDelayValue) &&
-								!StringUtils.hasText(fixedRateValue) && !StringUtils.hasText(maxMessagesPerPollValue),
+				Assert.state(!StringUtils.hasText(triggerRef)
+						&& !StringUtils.hasText(executorRef)
+						&& !StringUtils.hasText(cron)
+						&& !StringUtils.hasText(fixedDelayValue)
+						&& !StringUtils.hasText(fixedRateValue)
+						&& !StringUtils.hasText(maxMessagesPerPollValue), // NOSONAR boolean complexity
 						"The '@Poller' 'ref' attribute is mutually exclusive with other attributes.");
 				pollerMetadata = this.beanFactory.getBean(ref, PollerMetadata.class);
 			}

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

@@ -147,7 +147,7 @@ public class RouterAnnotationPostProcessor extends AbstractMethodAnnotationPostP
 		String applySequence = MessagingAnnotationUtils.resolveAttribute(annotations, "applySequence", String.class);
 		String ignoreSendFailures = MessagingAnnotationUtils.resolveAttribute(annotations, "ignoreSendFailures",
 				String.class);
-		return StringUtils.hasText(defaultOutputChannel) || !ObjectUtils.isEmpty(channelMappings)
+		return StringUtils.hasText(defaultOutputChannel) || !ObjectUtils.isEmpty(channelMappings) // NOSONAR complexity
 				|| StringUtils.hasText(prefix) || StringUtils.hasText(suffix) || StringUtils.hasText(resolutionRequired)
 				|| StringUtils.hasText(applySequence) || StringUtils.hasText(ignoreSendFailures);
 	}

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

@@ -51,7 +51,7 @@ public abstract class AbstractInboundGatewayParser extends AbstractSimpleBeanDef
 
 	@Override
 	protected boolean isEligibleAttribute(String attributeName) {
-		return !attributeName.equals("name") && !attributeName.equals("request-channel")
+		return !attributeName.equals("name") && !attributeName.equals("request-channel") // NOSONAR boolean complexity
 				&& !attributeName.equals("error-channel")
 				&& !attributeName.equals("reply-channel") && super.isEligibleAttribute(attributeName);
 	}

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

@@ -65,16 +65,16 @@ public class DefaultInboundChannelAdapterParser extends AbstractPollingInboundCh
 		boolean hasExpressionElement = expressionElement != null;
 		boolean hasMethod = StringUtils.hasText(methodName);
 
-		if (!hasInnerDef && !hasRef && !hasExpression && !hasScriptElement && !hasExpressionElement) {
+		if (!hasInnerDef && !hasRef && !hasExpression && !hasScriptElement && !hasExpressionElement) { // NOSONAR
 			parserContext.getReaderContext().error(
-					"Exactly one of the 'ref', 'expression', inner bean, <script> or <expression> is required.", element);
+				"Exactly one of the 'ref', 'expression', inner bean, <script> or <expression> is required.", element);
 		}
 
 		if (hasInnerDef) {
 			if (hasRef || hasExpression) {
 				parserContext.getReaderContext().error(
-						"Neither 'ref' nor 'expression' are permitted when an inner bean (<bean/>) is configured on element " +
-								IntegrationNamespaceUtils.createElementDescription(element) + ".", source);
+						"Neither 'ref' nor 'expression' are permitted when an inner bean (<bean/>) is configured on "
+						+ "element " + IntegrationNamespaceUtils.createElementDescription(element) + ".", source);
 				return null;
 			}
 			if (hasMethod) {
@@ -87,8 +87,9 @@ public class DefaultInboundChannelAdapterParser extends AbstractPollingInboundCh
 		else if (hasScriptElement) {
 			if (hasRef || hasMethod || hasExpression) {
 				parserContext.getReaderContext().error(
-						"Neither 'ref' and 'method' nor 'expression' are permitted when an inner script element is configured on element " +
-								IntegrationNamespaceUtils.createElementDescription(element) + ".", source);
+						"Neither 'ref' and 'method' nor 'expression' are permitted when an inner script element is "
+						+ "configured on element "
+						+ IntegrationNamespaceUtils.createElementDescription(element) + ".", source);
 				return null;
 			}
 			BeanDefinition scriptBeanDefinition = parserContext.getDelegate().parseCustomElement(scriptElement);
@@ -101,7 +102,8 @@ public class DefaultInboundChannelAdapterParser extends AbstractPollingInboundCh
 		else if (hasExpression || hasExpressionElement) {
 			if (hasRef || hasMethod) {
 				parserContext.getReaderContext().error(
-						"The 'ref' and 'method' attributes can't be used with 'expression' attribute or inner <expression>.", element);
+						"The 'ref' and 'method' attributes can't be used with 'expression' attribute or inner "
+						+ "<expression>.", element);
 				return null;
 			}
 			if (hasExpression & hasExpressionElement) {
@@ -124,9 +126,11 @@ public class DefaultInboundChannelAdapterParser extends AbstractPollingInboundCh
 		return result;
 	}
 
-	private BeanMetadataElement parseMethodInvokingSource(BeanMetadataElement targetObject, String methodName, Element element,
-			ParserContext parserContext) {
-		BeanDefinitionBuilder sourceBuilder = BeanDefinitionBuilder.genericBeanDefinition(MethodInvokingMessageSource.class);
+	private BeanMetadataElement parseMethodInvokingSource(BeanMetadataElement targetObject, String methodName,
+			Element element, ParserContext parserContext) {
+
+		BeanDefinitionBuilder sourceBuilder = BeanDefinitionBuilder
+				.genericBeanDefinition(MethodInvokingMessageSource.class);
 		sourceBuilder.addPropertyValue("object", targetObject);
 		sourceBuilder.addPropertyValue("methodName", methodName);
 		this.parseHeaderExpressions(sourceBuilder, element, parserContext);
@@ -135,7 +139,9 @@ public class DefaultInboundChannelAdapterParser extends AbstractPollingInboundCh
 
 	private BeanMetadataElement parseExpression(String expressionString, Element expressionElement, Element element,
 			ParserContext parserContext) {
-		BeanDefinitionBuilder sourceBuilder = BeanDefinitionBuilder.genericBeanDefinition(ExpressionEvaluatingMessageSource.class);
+
+		BeanDefinitionBuilder sourceBuilder = BeanDefinitionBuilder
+				.genericBeanDefinition(ExpressionEvaluatingMessageSource.class);
 
 		BeanDefinition expressionDef = null;
 
@@ -166,8 +172,9 @@ public class DefaultInboundChannelAdapterParser extends AbstractPollingInboundCh
 			ManagedMap<String, Object> headerExpressions = new ManagedMap<String, Object>();
 			for (Element headerElement : headerElements) {
 				String headerName = headerElement.getAttribute("name");
-				BeanDefinition expressionDef = IntegrationNamespaceUtils.createExpressionDefinitionFromValueOrExpression("value",
-						"expression", parserContext, headerElement, true);
+				BeanDefinition expressionDef = IntegrationNamespaceUtils
+						.createExpressionDefinitionFromValueOrExpression("value",
+								"expression", parserContext, headerElement, true);
 				headerExpressions.put(headerName, expressionDef);
 			}
 			builder.addPropertyValue("headerExpressions", headerExpressions);

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

@@ -60,23 +60,24 @@ public class IdempotentReceiverInterceptorParser extends AbstractBeanDefinitionP
 
 		String endpoints = element.getAttribute("endpoint");
 
-		if (!hasSelector & !(hasKeyStrategy | hasKeyExpression)) {
+		if (!hasSelector && !(hasKeyStrategy || hasKeyExpression)) {
 			parserContext.getReaderContext().error("One of the 'selector', 'key-strategy' or 'key-expression' " +
 					"attributes must be provided", source);
 		}
 
-		if (hasSelector & (hasStore | hasKeyStrategy | hasKeyExpression | hasValueStrategy | hasValueExpression)) {
+		if (hasSelector && (hasStore || hasKeyStrategy || hasKeyExpression || hasValueStrategy // NOSONAR complexity
+				|| hasValueExpression)) {
 			parserContext.getReaderContext().error("The 'selector' attribute is mutually exclusive with " +
 					"'metadata-store', 'key-strategy', 'key-expression', 'value-strategy' " +
 					"or 'value-expression'", source);
 		}
 
-		if (hasKeyStrategy & hasKeyExpression) {
+		if (hasKeyStrategy && hasKeyExpression) {
 			parserContext.getReaderContext().error("The 'key-strategy' and 'key-expression' attributes " +
 					"are mutually exclusive", source);
 		}
 
-		if (hasValueStrategy & hasValueExpression) {
+		if (hasValueStrategy && hasValueExpression) {
 			parserContext.getReaderContext().error("The 'value-strategy' and 'value-expression' attributes " +
 					"are mutually exclusive", source);
 		}

spring-integration-core/src/main/java/org/springframework/integration/dispatcher/AggregateMessageDeliveryException.java

@@ -58,7 +58,8 @@ public class AggregateMessageDeliveryException extends MessageDeliveryException
 	@Override
 	public String getMessage() {
 		String baseMessage = super.getMessage();
-		StringBuilder message = new StringBuilder(appendPeriodIfNecessary(baseMessage) + " Multiple causes:\n");
+		StringBuilder message = new StringBuilder(appendPeriodIfNecessary(baseMessage))
+				.append(" Multiple causes:\n");
 		for (Exception exception : this.aggregatedExceptions) {
 			message.append("    " + exception.getMessage() + "\n");
 		}

spring-integration-core/src/main/java/org/springframework/integration/dsl/IntegrationFlowDefinition.java

@@ -3114,7 +3114,7 @@ public abstract class IntegrationFlowDefinition<B extends IntegrationFlowDefinit
 	}
 
 	@SuppressWarnings("unchecked")
-	protected final B _this() {
+	protected final B _this() { // NOSONAR name
 		return (B) this;
 	}
 

spring-integration-core/src/main/java/org/springframework/integration/dsl/context/IntegrationFlowLifecycleAdvice.java

@@ -113,6 +113,10 @@ class IntegrationFlowLifecycleAdvice implements MethodInterceptor {
 						result = this.delegate.getPhase();
 					}
 					break;
+
+				default:
+					break;
+
 			}
 		}
 

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

@@ -547,10 +547,10 @@ public class GatewayProxyFactoryBean extends AbstractEndpoint
 					throw t;
 				}
 			}
-			if (t instanceof RuntimeException
+			if (t instanceof RuntimeException // NOSONAR boolean complexity
 					&& !(t instanceof MessagingException)
 					&& !(t instanceof UndeclaredThrowableException)
-					&& !(t instanceof IllegalStateException && ("Unexpected exception thrown").equals(t.getMessage()))) {
+					&& !(t instanceof IllegalStateException && "Unexpected exception thrown".equals(t.getMessage()))) {
 				throw t;
 			}
 			t = t.getCause();

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

@@ -85,9 +85,9 @@ public class LoggingHandler extends AbstractMessageHandler {
 			return Level.valueOf(level.toUpperCase());
 		}
 		catch (@SuppressWarnings("unused") IllegalArgumentException e) {
-			throw new IllegalArgumentException("Invalid log level '" + level
+			throw new IllegalArgumentException("Invalid log level '" + level // NOSONAR lost stack trace
 					+ "'. The (case-insensitive) supported values are: "
-					+ StringUtils.arrayToCommaDelimitedString(Level.values())); // NOSONAR lost stack trace
+					+ StringUtils.arrayToCommaDelimitedString(Level.values()));
 		}
 	}
 

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

@@ -40,7 +40,7 @@ public abstract class AbstractHandleMessageAdvice extends IntegrationObjectSuppo
 		Method method = invocation.getMethod();
 		Object invocationThis = invocation.getThis();
 		Object[] arguments = invocation.getArguments();
-		boolean isMessageHandler = invocationThis != null && invocationThis instanceof MessageHandler;
+		boolean isMessageHandler = invocationThis instanceof MessageHandler;
 		boolean isMessageMethod = method.getName().equals("handleMessage")
 				&& (arguments.length == 1 && arguments[0] instanceof Message);
 		if (!isMessageHandler || !isMessageMethod) {
@@ -59,6 +59,6 @@ public abstract class AbstractHandleMessageAdvice extends IntegrationObjectSuppo
 		return doInvoke(invocation, message);
 	}
 
-	protected abstract Object doInvoke(MethodInvocation invocation, Message<?> message) throws Throwable;
+	protected abstract Object doInvoke(MethodInvocation invocation, Message<?> message) throws Throwable; // NOSONAR
 
 }

spring-integration-core/src/main/java/org/springframework/integration/json/JsonPropertyAccessor.java

@@ -68,7 +68,7 @@ public class JsonPropertyAccessor implements PropertyAccessor {
 
 	@Override
 	public Class<?>[] getSpecificTargetClasses() {
-		return SUPPORTED_CLASSES;
+		return SUPPORTED_CLASSES; // NOSONAR - expose internals
 	}
 
 	@Override

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

@@ -48,7 +48,7 @@ public class MapBuilder<B extends MapBuilder<B, K, V>, K, V> {
 	}
 
 	@SuppressWarnings("unchecked")
-	protected final B _this() {
+	protected final B _this() { // NOSONAR name
 		return (B) this;
 	}
 

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

@@ -111,7 +111,7 @@ public class MutableMessage<T> implements Message<T>, Serializable {
 		if (this == obj) {
 			return true;
 		}
-		if (obj != null && obj instanceof MutableMessage<?>) {
+		if (obj instanceof MutableMessage<?>) {
 			MutableMessage<?> other = (MutableMessage<?>) obj;
 			UUID thisId = this.headers.getId();
 			UUID otherId = other.headers.getId();

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

@@ -21,7 +21,6 @@ import java.io.UncheckedIOException;
 import java.nio.ByteBuffer;
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.HashMap;
 import java.util.Map;
 import java.util.stream.Collectors;
 
@@ -260,7 +259,7 @@ public class EmbeddedJsonHeadersMessageMapper implements BytesMessageMapper {
 					buffer.position(4);
 					@SuppressWarnings("unchecked")
 					Map<String, Object> headers = this.objectMapper.readValue(bytes, buffer.position(), headersLen,
-							HashMap.class);
+							Map.class);
 
 					buffer.position(buffer.position() + headersLen);
 					buffer.getInt();

spring-integration-core/src/main/java/org/springframework/integration/transaction/TransactionSynchronizationFactoryBean.java

@@ -41,7 +41,7 @@ import org.springframework.util.StringUtils;
 public class TransactionSynchronizationFactoryBean implements FactoryBean<DefaultTransactionSynchronizationFactory>,
 		BeanFactoryAware {
 
-	private final SpelExpressionParser PARSER = new SpelExpressionParser();
+	private static final SpelExpressionParser PARSER = new SpelExpressionParser();
 
 	private final AtomicInteger counter = new AtomicInteger();
 

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

@@ -108,7 +108,7 @@ public class BeanFactoryTypeConverter implements TypeConverter, BeanFactoryAware
 		if (sourceType != null) {
 			Class<?> sourceClass = sourceType.getType();
 			Class<?> targetClass = targetType.getType();
-			if ((sourceClass == MessageHeaders.class && targetClass == MessageHeaders.class) ||
+			if ((sourceClass == MessageHeaders.class && targetClass == MessageHeaders.class) || // NOSONAR
 				(sourceClass == MessageHistory.class && targetClass == MessageHistory.class) ||
 				(sourceType.isAssignableTo(targetType) && ClassUtils.isPrimitiveArray(sourceClass))) {
 				return value;

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

@@ -72,7 +72,7 @@ public final class MessagingAnnotationUtils {
 	}
 
 	public static boolean hasValue(Object value) {
-		return value != null && (!(value instanceof String) || (StringUtils.hasText((String) value)))
+		return value != null && (!(value instanceof String) || (StringUtils.hasText((String) value))) // NOSONAR
 				&& (!value.getClass().isArray() || ((Object[]) value).length > 0);
 	}
 
@@ -103,7 +103,7 @@ public final class MessagingAnnotationUtils {
 		Annotation match = null;
 		for (Annotation annotation : annotations) {
 			Class<? extends Annotation> type = annotation.annotationType();
-			if (type.equals(Payload.class)
+			if (type.equals(Payload.class) // NOSONAR boolean complexity
 					|| type.equals(Header.class)
 					|| type.equals(Headers.class)
 					|| (payloads && type.equals(Payloads.class))) {

spring-integration-core/src/test/java/org/springframework/integration/support/json/EmbeddedJsonHeadersMessageMapperTests.java

@@ -41,7 +41,7 @@ import com.fasterxml.jackson.databind.ObjectMapper;
 public class EmbeddedJsonHeadersMessageMapperTests {
 
 	@Test
-	public void testEmbedAll() throws Exception {
+	public void testEmbedAll() {
 		EmbeddedJsonHeadersMessageMapper mapper = new EmbeddedJsonHeadersMessageMapper();
 		GenericMessage<String> message = new GenericMessage<>("foo");
 		assertThat(mapper.toMessage(mapper.fromMessage(message))).isEqualTo(message);
@@ -92,7 +92,7 @@ public class EmbeddedJsonHeadersMessageMapperTests {
 	}
 
 	@Test
-	public void testBytesEmbedSome() throws Exception {
+	public void testBytesEmbedSome() {
 		EmbeddedJsonHeadersMessageMapper mapper = new EmbeddedJsonHeadersMessageMapper("I*");
 		GenericMessage<byte[]> message = new GenericMessage<>("foo".getBytes(), Collections.singletonMap("bar", "baz"));
 		byte[] bytes = mapper.fromMessage(message);
@@ -112,7 +112,7 @@ public class EmbeddedJsonHeadersMessageMapperTests {
 	}
 
 	@Test
-	public void testBytesEmbedAllJson() throws Exception {
+	public void testBytesEmbedAllJson() {
 		EmbeddedJsonHeadersMessageMapper mapper = new EmbeddedJsonHeadersMessageMapper();
 		mapper.setRawBytes(false);
 		GenericMessage<byte[]> message = new GenericMessage<>("foo".getBytes());
@@ -126,7 +126,7 @@ public class EmbeddedJsonHeadersMessageMapperTests {
 	}
 
 	@Test
-	public void testBytesDecodeAll() throws Exception {
+	public void testBytesDecodeAll() {
 		EmbeddedJsonHeadersMessageMapper mapper = new EmbeddedJsonHeadersMessageMapper();
 		GenericMessage<byte[]> message = new GenericMessage<>("foo".getBytes());
 		Message<?> decoded = mapper.toMessage(mapper.fromMessage(message));