Register bean for IntComponentScanRegistrar

To avoid duplication for scanning register a `IntegrationComponentScanRegistrar`
as a bean by itself and check for its presence before scanning

* Exclude this bean definition from the AOT since its logic has already passed on AOT generation
and we don't need this bean at runtime any more

Author: artembilan

spring-integration-core/src/main/java/org/springframework/integration/aot/IntegrationBeanRegistrationExcludeFilter.java

@@ -21,6 +21,7 @@
 import org.springframework.beans.factory.aot.BeanRegistrationExcludeFilter;
 import org.springframework.beans.factory.support.RegisteredBean;
 import org.springframework.integration.config.DefaultConfiguringBeanFactoryPostProcessor;
+import org.springframework.integration.config.IntegrationComponentScanRegistrar;
 import org.springframework.integration.config.IntegrationConfigurationBeanFactoryPostProcessor;
 
 /**
@@ -39,7 +40,8 @@ class IntegrationBeanRegistrationExcludeFilter implements BeanRegistrationExclud
 	public boolean isExcludedFromAotProcessing(RegisteredBean registeredBean) {
 		Class<?> beanClass = registeredBean.getBeanClass();
 		return Arrays.asList(DefaultConfiguringBeanFactoryPostProcessor.class,
-						IntegrationConfigurationBeanFactoryPostProcessor.class)
+						IntegrationConfigurationBeanFactoryPostProcessor.class,
+						IntegrationComponentScanRegistrar.class)
 				.contains(beanClass);
 	}
 

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

@@ -25,13 +25,18 @@
 import java.util.Set;
 import java.util.regex.Pattern;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
 import org.springframework.beans.BeanUtils;
 import org.springframework.beans.factory.Aware;
 import org.springframework.beans.factory.BeanClassLoaderAware;
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.BeanFactoryAware;
 import org.springframework.beans.factory.annotation.AnnotatedBeanDefinition;
+import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.beans.factory.config.ConfigurableBeanFactory;
+import org.springframework.beans.factory.support.BeanDefinitionBuilder;
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
 import org.springframework.beans.factory.support.BeanNameGenerator;
 import org.springframework.context.EnvironmentAware;
@@ -66,6 +71,10 @@
 public class IntegrationComponentScanRegistrar implements ImportBeanDefinitionRegistrar,
 		ResourceLoaderAware, EnvironmentAware {
 
+	private static final Log LOGGER = LogFactory.getLog(IntegrationComponentScanRegistrar.class);
+
+	private static final String BEAN_NAME = IntegrationComponentScanRegistrar.class.getName();
+
 	private final List<TypeFilter> defaultFilters = new ArrayList<>();
 
 	private ResourceLoader resourceLoader;
@@ -94,6 +103,16 @@ public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, B
 
 		Assert.notNull(componentScan, "The '@IntegrationComponentScan' must be present for using this registrar");
 
+		if (registry.containsBeanDefinition(BEAN_NAME)) {
+			LOGGER.warn("Only one '@IntegrationComponentScan' can be present.\nConsider to merge them all to one.");
+			return;
+		}
+
+		registry.registerBeanDefinition(BEAN_NAME,
+				BeanDefinitionBuilder.genericBeanDefinition(IntegrationComponentScanRegistrar.class, () -> this)
+						.setRole(BeanDefinition.ROLE_INFRASTRUCTURE)
+						.getBeanDefinition());
+
 		Collection<String> basePackages = getBasePackages(componentScan, registry);
 
 		if (basePackages.isEmpty()) {