GH-10083: Apply Nullability to HTTP module (#10319)

Related to: #10083

The change affects some core classes, since `getBeanName()` cannot be null after a proper bean initialization

* Add slight code flow improvement in the `BaseHttpInboundEndpoint` implementations regarding `validate()` method
* Fix `DefaultHttpHeaderMapper` tests where a `ConversionService` is required
* Fix `StandardIntegrationFlowContext.getBeanName()` for `this.` prefix

Author: artembilan

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

@@ -75,7 +75,6 @@ public interface ComponentSourceAware extends BeanNameAware {
 	 * Return the bean name populated by the {@link BeanNameAware#setBeanName(String)}.
 	 * @return the bean name.
 	 */
-	@Nullable
 	String getBeanName();
 
 }

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

@@ -117,7 +117,6 @@ public final void setBeanName(String beanName) {
 	}
 
 	@Override
-	@Nullable
 	public String getBeanName() {
 		return this.beanName;
 	}
@@ -127,7 +126,6 @@ public String getBeanName() {
 	 * If {@link #componentName} was not set this method will default to the 'beanName' of this component;
 	 */
 	@Override
-	@Nullable
 	public String getComponentName() {
 		return StringUtils.hasText(this.componentName) ? this.componentName : this.beanName;
 	}

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

@@ -80,7 +80,6 @@ public void setBeanName(String name) {
 		this.beanName = name;
 	}
 
-	@Nullable
 	@Override
 	public String getBeanName() {
 		return this.beanName;

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

@@ -76,7 +76,7 @@ public class StandardIntegrationFlow
 
 	private @Nullable MessageChannel inputChannel;
 
-	private @Nullable boolean running;
+	private boolean running;
 
 	@SuppressWarnings("NullAway.Init")
 	private String beanName;
@@ -125,7 +125,7 @@ public void setComponentDescription(String description) {
 	}
 
 	@Override
-	public @Nullable String getBeanName() {
+	public String getBeanName() {
 		return this.beanName;
 	}
 

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

@@ -376,6 +376,9 @@ private static final class IntegrationFlowComponentSourceAwareAdapter
 
 		private final IntegrationFlow delegate;
 
+		@SuppressWarnings("NullAway.Init")
+		private String beanName;
+
 		private @Nullable Object beanSource;
 
 		private @Nullable String beanDescription;
@@ -404,15 +407,14 @@ public void setComponentDescription(String description) {
 			return this.beanDescription;
 		}
 
-		@Nullable
 		@Override
 		public String getBeanName() {
-			return null;
+			return this.beanName;
 		}
 
 		@Override
 		public void setBeanName(String name) {
-
+			this.beanName = name;
 		}
 
 		@Override

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

@@ -74,7 +74,7 @@ public Object processMessage(Message<?> message) {
 		@SuppressWarnings("unchecked")
 		List<Object> arguments =
 				message.getHeaders().get(IntegrationMessageHeaderAccessor.CONTROL_BUS_ARGUMENTS, List.class);
-		Class<?>[] parameterTypes = new Class<?>[0];
+		Class<?>[] parameterTypes = {};
 		if (!CollectionUtils.isEmpty(arguments)) {
 			parameterTypes =
 					arguments.stream()

spring-integration-http/src/main/java/org/springframework/integration/http/config/ControlBusControllerConfiguration.java

@@ -18,6 +18,7 @@
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.beans.factory.config.BeanDefinition;
@@ -42,9 +43,10 @@
 @Role(BeanDefinition.ROLE_INFRASTRUCTURE)
 public class ControlBusControllerConfiguration {
 
-	private static final Log LOGGER = LogFactory.getLog(IntegrationGraphControllerRegistrar.class);
+	private static final Log LOGGER = LogFactory.getLog(ControlBusControllerConfiguration.class);
 
 	@Bean
+	@Nullable
 	ControlBusController controlBusController(ControlBusCommandRegistry controlBusCommandRegistry,
 			ObjectProvider<FormattingConversionService> conversionService) {
 
@@ -56,7 +58,7 @@ ControlBusController controlBusController(ControlBusCommandRegistry controlBusCo
 
 		controlBusCommandRegistry.setEagerInitialization(true);
 
-		return new ControlBusController(controlBusCommandRegistry, conversionService.getIfUnique());
+		return new ControlBusController(controlBusCommandRegistry, conversionService.getObject());
 	}
 
 }

spring-integration-http/src/main/java/org/springframework/integration/http/config/HttpContextUtils.java

@@ -19,6 +19,8 @@
 import java.util.HashMap;
 import java.util.Map;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.core.annotation.AnnotationUtils;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.ObjectUtils;
@@ -85,17 +87,18 @@ private HttpContextUtils() {
 	 * @return the {@link RequestMapping} annotation.
 	 * @since 5.0
 	 */
-	public static RequestMapping convertRequestMappingToAnnotation(
+	public static @Nullable RequestMapping convertRequestMappingToAnnotation(
 			org.springframework.integration.http.inbound.RequestMapping requestMapping) {
 
-		if (ObjectUtils.isEmpty(requestMapping.getPathPatterns())) {
+		String[] pathPatterns = requestMapping.getPathPatterns();
+		if (ObjectUtils.isEmpty(pathPatterns)) {
 			return null;
 		}
 
 		Map<String, Object> requestMappingAttributes = new HashMap<>();
 		requestMappingAttributes.put("name", requestMapping.getName());
-		requestMappingAttributes.put("value", requestMapping.getPathPatterns());
-		requestMappingAttributes.put("path", requestMapping.getPathPatterns());
+		requestMappingAttributes.put("value", pathPatterns);
+		requestMappingAttributes.put("path", pathPatterns);
 		requestMappingAttributes.put("method", requestMapping.getRequestMethods());
 		requestMappingAttributes.put("params", requestMapping.getParams());
 		requestMappingAttributes.put("headers", requestMapping.getHeaders());

spring-integration-http/src/main/java/org/springframework/integration/http/config/HttpOutboundChannelAdapterParser.java

@@ -55,7 +55,6 @@ protected AbstractBeanDefinition parseConsumer(Element element, ParserContext pa
 			if (StringUtils.hasText(mappedRequestHeaders)) {
 				parserContext.getReaderContext().error("The 'mapped-request-headers' attribute is not " +
 						"allowed when a 'header-mapper' has been specified.", parserContext.extractSource(element));
-				return null;
 			}
 			builder.addPropertyReference("headerMapper", headerMapper);
 		}

spring-integration-http/src/main/java/org/springframework/integration/http/config/HttpOutboundGatewayParser.java

@@ -58,7 +58,6 @@ protected BeanDefinitionBuilder parseHandler(Element element, ParserContext pars
 						.error("Neither 'mapped-request-headers' or 'mapped-response-headers' " +
 										"attributes are allowed when a 'header-mapper' has been specified.",
 								parserContext.extractSource(element));
-				return null;
 			}
 			builder.addPropertyReference("headerMapper", headerMapper);
 		}