Spring框架的AnnotationConfigApplicationContext初始化流程（2）

书接上一回到AnnotatedBeanDefinitionReader的初始化

public class AnnotatedBeanDefinitionReader {

    private final BeanDefinitionRegistry registry;

    private ConditionEvaluator conditionEvaluator;

    ......

    public AnnotatedBeanDefinitionReader(BeanDefinitionRegistry registry) {
       this(registry, getOrCreateEnvironment(registry));
    }


    public AnnotatedBeanDefinitionReader(BeanDefinitionRegistry registry, Environment environment) {
       Assert.notNull(registry, "BeanDefinitionRegistry must not be null");
       Assert.notNull(environment, "Environment must not be null");
       this.registry = registry;
       this.conditionEvaluator = new ConditionEvaluator(registry, environment, null);
       AnnotationConfigUtils.registerAnnotationConfigProcessors(this.registry);
    }
    
    ......
 }

重点方法是AnnotationConfigUtils类的registerAnnotationConfigProcessors方法

public static void registerAnnotationConfigProcessors(BeanDefinitionRegistry registry) {
    registerAnnotationConfigProcessors(registry, null);
}

public static Set<BeanDefinitionHolder> registerAnnotationConfigProcessors(
       BeanDefinitionRegistry registry, @Nullable Object source) {

    DefaultListableBeanFactory beanFactory = unwrapDefaultListableBeanFactory(registry);
    if (beanFactory != null) {
       if (!(beanFactory.getDependencyComparator() instanceof AnnotationAwareOrderComparator)) {
          beanFactory.setDependencyComparator(AnnotationAwareOrderComparator.INSTANCE);
       }
       if (!(beanFactory.getAutowireCandidateResolver() instanceof ContextAnnotationAutowireCandidateResolver)) {
          beanFactory.setAutowireCandidateResolver(new ContextAnnotationAutowireCandidateResolver());
       }
    }

    Set<BeanDefinitionHolder> beanDefs = new LinkedHashSet<>(8);

    if (!registry.containsBeanDefinition(CONFIGURATION_ANNOTATION_PROCESSOR_BEAN_NAME)) {
       RootBeanDefinition def = new RootBeanDefinition(ConfigurationClassPostProcessor.class);
       def.setSource(source);
       beanDefs.add(registerPostProcessor(registry, def, CONFIGURATION_ANNOTATION_PROCESSOR_BEAN_NAME));
    }

    if (!registry.containsBeanDefinition(AUTOWIRED_ANNOTATION_PROCESSOR_BEAN_NAME)) {
       RootBeanDefinition def = new RootBeanDefinition(AutowiredAnnotationBeanPostProcessor.class);
       def.setSource(source);
       beanDefs.add(registerPostProcessor(registry, def, AUTOWIRED_ANNOTATION_PROCESSOR_BEAN_NAME));
    }

    // Check for JSR-250 support, and if present add the CommonAnnotationBeanPostProcessor.
    if (jsr250Present && !registry.containsBeanDefinition(COMMON_ANNOTATION_PROCESSOR_BEAN_NAME)) {
       RootBeanDefinition def = new RootBeanDefinition(CommonAnnotationBeanPostProcessor.class);
       def.setSource(source);
       beanDefs.add(registerPostProcessor(registry, def, COMMON_ANNOTATION_PROCESSOR_BEAN_NAME));
    }

    // Check for JPA support, and if present add the PersistenceAnnotationBeanPostProcessor.
    if (jpaPresent && !registry.containsBeanDefinition(PERSISTENCE_ANNOTATION_PROCESSOR_BEAN_NAME)) {
       RootBeanDefinition def = new RootBeanDefinition();
       try {
          def.setBeanClass(ClassUtils.forName(PERSISTENCE_ANNOTATION_PROCESSOR_CLASS_NAME,
                AnnotationConfigUtils.class.getClassLoader()));
       }
       catch (ClassNotFoundException ex) {
          throw new IllegalStateException(
                "Cannot load optional framework class: " + PERSISTENCE_ANNOTATION_PROCESSOR_CLASS_NAME, ex);
       }
       def.setSource(source);
       beanDefs.add(registerPostProcessor(registry, def, PERSISTENCE_ANNOTATION_PROCESSOR_BEAN_NAME));
    }

    if (!registry.containsBeanDefinition(EVENT_LISTENER_PROCESSOR_BEAN_NAME)) {
       RootBeanDefinition def = new RootBeanDefinition(EventListenerMethodProcessor.class);
       def.setSource(source);
       beanDefs.add(registerPostProcessor(registry, def, EVENT_LISTENER_PROCESSOR_BEAN_NAME));
    }

    if (!registry.containsBeanDefinition(EVENT_LISTENER_FACTORY_BEAN_NAME)) {
       RootBeanDefinition def = new RootBeanDefinition(DefaultEventListenerFactory.class);
       def.setSource(source);
       beanDefs.add(registerPostProcessor(registry, def, EVENT_LISTENER_FACTORY_BEAN_NAME));
    }

    return beanDefs;
}

一般情况下会注入 org.springframework.context.annotation.ConfigurationClassPostProcessor、org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor、 org.springframework.context.annotation.CommonAnnotationBeanPostProcessor、 org.springframework.context.event.EventListenerMethodProcessor、org.springframework.context.event.DefaultEventListenerFactory这5个类 初始化AnnotatedBeanDefinitionReader顺便会往beanListenerFactory注入辅助类