GH-8611: Extract IntegrationConfigurationReport (#8660)

Fixes #8611

According to the latest Spring Framework requirements related to AOT the
`BeanDefinitionRegistryPostProcessor` must not do anything but only bean registrations

* Extract an `IntegrationConfigurationReport` component
and move `IntegrationProperties` printing over here out from the
`DefaultConfiguringBeanFactoryPostProcessor`
* Remove a `SmartInitializingSingleton` impl from the `DefaultConfiguringBeanFactoryPostProcessor`

Author: artembilan

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

@@ -16,17 +16,14 @@
 
 package org.springframework.integration.config;
 
-import java.io.PrintWriter;
-import java.io.StringWriter;
+import java.beans.Introspector;
 import java.util.HashSet;
-import java.util.Properties;
 import java.util.Set;
 import java.util.concurrent.ThreadPoolExecutor.CallerRunsPolicy;
 
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.HierarchicalBeanFactory;
-import org.springframework.beans.factory.SmartInitializingSingleton;
 import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.beans.factory.config.PropertiesFactoryBean;
@@ -74,8 +71,7 @@
  *
  * @see IntegrationContextUtils
  */
-public class DefaultConfiguringBeanFactoryPostProcessor
-		implements BeanDefinitionRegistryPostProcessor, SmartInitializingSingleton {
+public class DefaultConfiguringBeanFactoryPostProcessor implements BeanDefinitionRegistryPostProcessor {
 
 	private static final LogAccessor LOGGER = new LogAccessor(DefaultConfiguringBeanFactoryPostProcessor.class);
 
@@ -130,27 +126,13 @@ public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) t
 		registerArgumentResolverMessageConverter();
 		registerMessageHandlerMethodFactory();
 		registerListMessageHandlerMethodFactory();
+		registerIntegrationConfigurationReport();
 	}
 
 	@Override
 	public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
 	}
 
-	@Override
-	public void afterSingletonsInstantiated() {
-		if (LOGGER.isDebugEnabled()) {
-			Properties integrationProperties =
-					IntegrationContextUtils.getIntegrationProperties(this.beanFactory)
-							.toProperties();
-
-			StringWriter writer = new StringWriter();
-			integrationProperties.list(new PrintWriter(writer));
-			StringBuffer propertiesBuffer = writer.getBuffer()
-					.delete(0, "-- listing properties --".length());
-			LOGGER.debug("\nSpring Integration global properties:\n" + propertiesBuffer);
-		}
-	}
-
 	private void registerBeanFactoryChannelResolver() {
 		if (!this.beanFactory.containsBeanDefinition(ChannelResolverUtils.CHANNEL_RESOLVER_BEAN_NAME)) {
 			this.registry.registerBeanDefinition(ChannelResolverUtils.CHANNEL_RESOLVER_BEAN_NAME,
@@ -450,6 +432,13 @@ private void registerListMessageHandlerMethodFactory() {
 		}
 	}
 
+	private void registerIntegrationConfigurationReport() {
+		this.registry.registerBeanDefinition(Introspector.decapitalize(IntegrationConfigurationReport.class.getName()),
+				BeanDefinitionBuilder.genericBeanDefinition(IntegrationConfigurationReport.class)
+						.setRole(BeanDefinition.ROLE_INFRASTRUCTURE)
+						.getBeanDefinition());
+	}
+
 	private static BeanDefinitionBuilder createMessageHandlerMethodFactoryBeanDefinition(boolean listCapable) {
 		return BeanDefinitionBuilder.genericBeanDefinition(IntegrationMessageHandlerMethodFactory.class)
 				.addConstructorArgValue(listCapable)

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

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2023 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.integration.config;
+
+
+import java.io.PrintWriter;
+import java.io.StringWriter;
+import java.util.Properties;
+
+import org.springframework.beans.BeansException;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationContextAware;
+import org.springframework.context.ApplicationListener;
+import org.springframework.context.event.ContextRefreshedEvent;
+import org.springframework.core.log.LogAccessor;
+import org.springframework.integration.context.IntegrationContextUtils;
+
+/**
+ * An {@link org.springframework.beans.factory.config.BeanDefinition#ROLE_INFRASTRUCTURE}
+ * component to report Spring Integration relevant configuration state after application context is refreshed.
+ *
+ * @author Artem Bilan
+ *
+ * @since 6.2
+ */
+class IntegrationConfigurationReport
+		implements ApplicationContextAware, ApplicationListener<ContextRefreshedEvent> {
+
+	private static final LogAccessor LOGGER = new LogAccessor(IntegrationConfigurationReport.class);
+
+	private ApplicationContext applicationContext;
+
+	@Override
+	public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
+		this.applicationContext = applicationContext;
+	}
+
+	@Override
+	public void onApplicationEvent(ContextRefreshedEvent event) {
+		if (event.getApplicationContext().equals(this.applicationContext)) {
+			report();
+		}
+	}
+
+	private void report() {
+		printIntegrationProperties();
+	}
+
+	private void printIntegrationProperties() {
+		if (LOGGER.isDebugEnabled()) {
+			Properties integrationProperties =
+					IntegrationContextUtils.getIntegrationProperties(this.applicationContext)
+							.toProperties();
+
+			StringWriter writer = new StringWriter();
+			integrationProperties.list(new PrintWriter(writer));
+			StringBuffer propertiesBuffer = writer.getBuffer()
+					.delete(0, "-- listing properties --".length());
+			LOGGER.debug("\nSpring Integration global properties:\n" + propertiesBuffer);
+		}
+	}
+
+}