（Spring源碼分析）AnnotationConfigApplicationContext容器初始化 refresh()#registerBeanPostProcessors

AnnotationConfigApplicationContext容器初始化目錄
（Spring源碼分析）AnnotationConfigApplicationContext容器初始化 this() && register()
（Spring源碼分析）AnnotationConfigApplicationContext容器初始化 refresh()#invokeBeanFactoryPostProcessors
（Spring源碼分析）AnnotationConfigApplicationContext容器初始化 refresh()#registerBeanPostProcessors
（Spring源碼分析）AnnotationConfigApplicationContext容器初始化 refresh()#finishBeanFactoryInitialization

3.2、registerBeanPostProcessors(beanFactory)

protected void registerBeanPostProcessors(ConfigurableListableBeanFactory beanFactory) {
  PostProcessorRegistrationDelegate.registerBeanPostProcessors(beanFactory, this);
}

PostProcessorRegistrationDelegate.registerBeanPostProcessors(beanFactory, this)

public static void registerBeanPostProcessors(
  ConfigurableListableBeanFactory beanFactory, AbstractApplicationContext applicationContext) {
  // 查詢beanDefinitionMap中所有實現了BeanPostProcessor接口的類名稱數組
  String[] postProcessorNames = beanFactory.getBeanNamesForType(BeanPostProcessor.class, true, false);

  // Register BeanPostProcessorChecker that logs an info message when
  // a bean is created during BeanPostProcessor instantiation, i.e. when
  // a bean is not eligible for getting processed by all BeanPostProcessors.
  // 將beanFactory作爲BeanPostProcessors作爲後置處理器添加到的beanPostProcessors中
  int beanProcessorTargetCount = beanFactory.getBeanPostProcessorCount() + 1 + postProcessorNames.length;
  beanFactory.addBeanPostProcessor(new BeanPostProcessorChecker(beanFactory, beanProcessorTargetCount));

  // Separate between BeanPostProcessors that implement PriorityOrdered,
  // Ordered, and the rest.
  // 對實現了不同接口的後置處理器進行分類
  List<BeanPostProcessor> priorityOrderedPostProcessors = new ArrayList<>();
  List<BeanPostProcessor> internalPostProcessors = new ArrayList<>();
  List<String> orderedPostProcessorNames = new ArrayList<>();
  List<String> nonOrderedPostProcessorNames = new ArrayList<>();
  for (String ppName : postProcessorNames) {
    if (beanFactory.isTypeMatch(ppName, PriorityOrdered.class)) {
      BeanPostProcessor pp = beanFactory.getBean(ppName, BeanPostProcessor.class);
      priorityOrderedPostProcessors.add(pp);
      if (pp instanceof MergedBeanDefinitionPostProcessor) {
        internalPostProcessors.add(pp);
      }
    }
    else if (beanFactory.isTypeMatch(ppName, Ordered.class)) {
      orderedPostProcessorNames.add(ppName);
    }
    else {
      nonOrderedPostProcessorNames.add(ppName);
    }
  }

  // 註冊實現了PriorityOrdered接口的處理器
  // First, register the BeanPostProcessors that implement PriorityOrdered.
  sortPostProcessors(priorityOrderedPostProcessors, beanFactory);
  registerBeanPostProcessors(beanFactory, priorityOrderedPostProcessors);

  // Next, register the BeanPostProcessors that implement Ordered.
  // 註冊實現了Ordered接口的處理器
  List<BeanPostProcessor> orderedPostProcessors = new ArrayList<>();
  for (String ppName : orderedPostProcessorNames) {
    BeanPostProcessor pp = beanFactory.getBean(ppName, BeanPostProcessor.class);
    orderedPostProcessors.add(pp);
    if (pp instanceof MergedBeanDefinitionPostProcessor) {
      internalPostProcessors.add(pp);
    }
  }
  sortPostProcessors(orderedPostProcessors, beanFactory);
  registerBeanPostProcessors(beanFactory, orderedPostProcessors);

  // Now, register all regular BeanPostProcessors.
  // 註冊既沒有實現PriorityOrdered接口的也沒有實現Ordered接口的處理器
  List<BeanPostProcessor> nonOrderedPostProcessors = new ArrayList<>();
  for (String ppName : nonOrderedPostProcessorNames) {
    BeanPostProcessor pp = beanFactory.getBean(ppName, BeanPostProcessor.class);
    nonOrderedPostProcessors.add(pp);
    if (pp instanceof MergedBeanDefinitionPostProcessor) {
      internalPostProcessors.add(pp);
    }
  }
  registerBeanPostProcessors(beanFactory, nonOrderedPostProcessors);

  // Finally, re-register all internal BeanPostProcessors.
  // 最後，重新註冊所有的後置處理器
  sortPostProcessors(internalPostProcessors, beanFactory);
  registerBeanPostProcessors(beanFactory, internalPostProcessors);

  // Re-register post-processor for detecting inner beans as ApplicationListeners,
  // moving it to the end of the processor chain (for picking up proxies etc).
  beanFactory.addBeanPostProcessor(new ApplicationListenerDetector(applicationContext));
}

registerBeanPostProcessors(beanFactory, priorityOrderedPostProcessors)

private static void registerBeanPostProcessors(
  ConfigurableListableBeanFactory beanFactory, List<BeanPostProcessor> postProcessors) {
  for (BeanPostProcessor postProcessor : postProcessors) {
    beanFactory.addBeanPostProcessor(postProcessor);
  }
}

beanFactory.addBeanPostProcessor(postProcessor)

@Override
public void addBeanPostProcessor(BeanPostProcessor beanPostProcessor) {
  Assert.notNull(beanPostProcessor, "BeanPostProcessor must not be null");
  // Remove from old position, if any
  this.beanPostProcessors.remove(beanPostProcessor);
  // Track whether it is instantiation/destruction aware
  if (beanPostProcessor instanceof InstantiationAwareBeanPostProcessor) {
    this.hasInstantiationAwareBeanPostProcessors = true;
  }
  if (beanPostProcessor instanceof DestructionAwareBeanPostProcessor) {
    this.hasDestructionAwareBeanPostProcessors = true;
  }
  // Add to end of list
  this.beanPostProcessors.add(beanPostProcessor);
}