Avoid early initializations

This commit flags the two `BeanPostProcessors` registered by the
embedded support as `synthetic` so that they don't trigger an early
initialization of other components.

Closes gh-8467

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/EmbeddedServletContainerAutoConfiguration.java

 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -58,6 +58,7 @@ import org.springframework.util.ObjectUtils;
  * @author Phillip Webb
  * @author Dave Syer
  * @author Ivan Sopov
+ * @author Stephane Nicoll
  */
 @AutoConfigureOrder(Ordered.HIGHEST_PRECEDENCE)
 @Configuration
@@ -136,17 +137,21 @@ public class EmbeddedServletContainerAutoConfiguration {
 			if (ObjectUtils.isEmpty(this.beanFactory.getBeanNamesForType(
 					EmbeddedServletContainerCustomizerBeanPostProcessor.class, true,
 					false))) {
+				RootBeanDefinition beanDefinition = new RootBeanDefinition(
+						EmbeddedServletContainerCustomizerBeanPostProcessor.class);
+				beanDefinition.setSynthetic(true);
 				registry.registerBeanDefinition(
 						"embeddedServletContainerCustomizerBeanPostProcessor",
-						new RootBeanDefinition(
-								EmbeddedServletContainerCustomizerBeanPostProcessor.class));
+						beanDefinition);
 
 			}
 			if (ObjectUtils.isEmpty(this.beanFactory.getBeanNamesForType(
 					ErrorPageRegistrarBeanPostProcessor.class, true, false))) {
+				RootBeanDefinition beanDefinition = new RootBeanDefinition(
+						ErrorPageRegistrarBeanPostProcessor.class);
+				beanDefinition.setSynthetic(true);
 				registry.registerBeanDefinition("errorPageRegistrarBeanPostProcessor",
-						new RootBeanDefinition(
-								ErrorPageRegistrarBeanPostProcessor.class));
+						beanDefinition);
 
 			}
 		}

spring-boot/src/main/java/org/springframework/boot/context/embedded/EmbeddedServletContainerCustomizerBeanPostProcessor.java

 /*
- * Copyright 2012-2014 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -22,9 +22,10 @@ import java.util.Collections;
 import java.util.List;
 
 import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.BeanFactory;
+import org.springframework.beans.factory.BeanFactoryAware;
+import org.springframework.beans.factory.ListableBeanFactory;
 import org.springframework.beans.factory.config.BeanPostProcessor;
-import org.springframework.context.ApplicationContext;
-import org.springframework.context.ApplicationContextAware;
 import org.springframework.core.annotation.AnnotationAwareOrderComparator;
 
 /**
@@ -33,18 +34,18 @@ import org.springframework.core.annotation.AnnotationAwareOrderComparator;
  *
  * @author Dave Syer
  * @author Phillip Webb
+ * @author Stephane Nicoll
  */
 public class EmbeddedServletContainerCustomizerBeanPostProcessor
-		implements BeanPostProcessor, ApplicationContextAware {
+		implements BeanPostProcessor, BeanFactoryAware {
 
-	private ApplicationContext applicationContext;
+	private ListableBeanFactory beanFactory;
 
 	private List<EmbeddedServletContainerCustomizer> customizers;
 
 	@Override
-	public void setApplicationContext(ApplicationContext applicationContext)
-			throws BeansException {
-		this.applicationContext = applicationContext;
+	public void setBeanFactory(BeanFactory beanFactory) {
+		this.beanFactory = (ListableBeanFactory) beanFactory;
 	}
 
 	@Override
@@ -73,7 +74,7 @@ public class EmbeddedServletContainerCustomizerBeanPostProcessor
 		if (this.customizers == null) {
 			// Look up does not include the parent context
 			this.customizers = new ArrayList<EmbeddedServletContainerCustomizer>(
-					this.applicationContext
+					this.beanFactory
 							.getBeansOfType(EmbeddedServletContainerCustomizer.class,
 									false, false)
 							.values());

spring-boot/src/main/java/org/springframework/boot/web/servlet/ErrorPageRegistrarBeanPostProcessor.java

 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -22,9 +22,10 @@ import java.util.Collections;
 import java.util.List;
 
 import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.BeanFactory;
+import org.springframework.beans.factory.BeanFactoryAware;
+import org.springframework.beans.factory.ListableBeanFactory;
 import org.springframework.beans.factory.config.BeanPostProcessor;
-import org.springframework.context.ApplicationContext;
-import org.springframework.context.ApplicationContextAware;
 import org.springframework.core.annotation.AnnotationAwareOrderComparator;
 
 /**
@@ -32,19 +33,19 @@ import org.springframework.core.annotation.AnnotationAwareOrderComparator;
  * factory to {@link ErrorPageRegistry} beans.
  *
  * @author Phillip Webb
+ * @author Stephane Nicoll
  * @since 1.4.0
  */
 public class ErrorPageRegistrarBeanPostProcessor
-		implements BeanPostProcessor, ApplicationContextAware {
+		implements BeanPostProcessor, BeanFactoryAware {
 
-	private ApplicationContext applicationContext;
+	private ListableBeanFactory beanFactory;
 
 	private List<ErrorPageRegistrar> registrars;
 
 	@Override
-	public void setApplicationContext(ApplicationContext applicationContext)
-			throws BeansException {
-		this.applicationContext = applicationContext;
+	public void setBeanFactory(BeanFactory beanFactory) {
+		this.beanFactory = (ListableBeanFactory) beanFactory;
 	}
 
 	@Override
@@ -71,7 +72,7 @@ public class ErrorPageRegistrarBeanPostProcessor
 	private Collection<ErrorPageRegistrar> getRegistrars() {
 		if (this.registrars == null) {
 			// Look up does not include the parent context
-			this.registrars = new ArrayList<ErrorPageRegistrar>(this.applicationContext
+			this.registrars = new ArrayList<ErrorPageRegistrar>(this.beanFactory
 					.getBeansOfType(ErrorPageRegistrar.class, false, false).values());
 			Collections.sort(this.registrars, AnnotationAwareOrderComparator.INSTANCE);
 			this.registrars = Collections.unmodifiableList(this.registrars);