- 执行剩下的BeanFactoryPostProcessor的后置处理器
-
- EventListenerMethodProcessor的postProcessBeanFactory
- DefaultListableBeanFactory的clearMetadataCache进行元数据缓存清除
- AbstractApplicationContext的invokeBeanFactoryPostProcessors
- 总结
- registerBeanPostProcessors注册bean后置处理器
执行剩下的BeanFactoryPostProcessor的后置处理器
首先先按PriorityOrdered，Ordered和一般的BeanFactoryPostProcessor没处理过的处理器分成三个集合，然后按顺序分别进行处理，这里面除了我们自定义的，就是内部的EventListenerMethodProcessor了。
String[] postProcessorNames =
beanFactory.getBeanNamesForType(BeanFactoryPostProcessor.class, true, false);
//三种优先级区分
// Separate between BeanFactoryPostProcessors that implement PriorityOrdered,
// Ordered, and the rest.
List<BeanFactoryPostProcessor> priorityOrderedPostProcessors = new ArrayList<>();
List<String> orderedPostProcessorNames = new ArrayList<>();
List<String> nonOrderedPostProcessorNames = new ArrayList<>();
for (String ppName : postProcessorNames) {
if (processedBeans.contains(ppName)) {
//处理过的就不处理
// skip - already processed in first phase above
}
else if (beanFactory.isTypeMatch(ppName, PriorityOrdered.class)) {
priorityOrderedPostProcessors.add(beanFactory.getBean(ppName, BeanFactoryPostProcessor.class));
}
else if (beanFactory.isTypeMatch(ppName, Ordered.class)) {
orderedPostProcessorNames.add(ppName);
}
else {
nonOrderedPostProcessorNames.add(ppName);
}
}
//先处理priorityOrderedPostProcessors排序和回调
// First, invoke the BeanFactoryPostProcessors that implement PriorityOrdered.
sortPostProcessors(priorityOrderedPostProcessors, beanFactory);
invokeBeanFactoryPostProcessors(priorityOrderedPostProcessors, beanFactory);
//再处理orderedPostProcessors排序和回调
// Next, invoke the BeanFactoryPostProcessors that implement Ordered.
List<BeanFactoryPostProcessor> orderedPostProcessors = new ArrayList<>(orderedPostProcessorNames.size());
for (String postProcessorName : orderedPostProcessorNames) {
orderedPostProcessors.add(beanFactory.getBean(postProcessorName, BeanFactoryPostProcessor.class));
}
sortPostProcessors(orderedPostProcessors, beanFactory);
invokeBeanFactoryPostProcessors(orderedPostProcessors, beanFactory);
//最后是剩下的
// Finally, invoke all other BeanFactoryPostProcessors.
List<BeanFactoryPostProcessor> nonOrderedPostProcessors = new ArrayList<>(nonOrderedPostProcessorNames.size());
for (String postProcessorName : nonOrderedPostProcessorNames) {
nonOrderedPostProcessors.add(beanFactory.getBean(postProcessorName, BeanFactoryPostProcessor.class));
}
invokeBeanFactoryPostProcessors(nonOrderedPostProcessors, beanFactory);
EventListenerMethodProcessor的postProcessBeanFactory
从bean名字中查找并创建EventListenerFactory类型的对象返回，然后保存到eventListenerFactories 中，其实就是创建事件监听工厂，后面可以创建事件监听器。
@Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) {
this.beanFactory = beanFactory;
Map<String, EventListenerFactory> beans = beanFactory.getBeansOfType(EventListenerFactory.class, false, false);
List<EventListenerFactory> factories = new ArrayList<>(beans.values());
AnnotationAwareOrderComparator.sort(factories);
this.eventListenerFactories = factories;
}
DefaultListableBeanFactory的clearMetadataCache进行元数据缓存清除
主要是判断是否已经创建了，没创建的话BeanDefinition的stale=true，创建的就不处理了。最后把allBeanNamesByType和singletonBeanNamesByType的缓存清除。
@Override
public void clearMetadataCache() {
super.clearMetadataCache();
clearByTypeCache();
}
public void clearMetadataCache() {
this.mergedBeanDefinitions.forEach((beanName, bd) -> {
if (!isBeanEligibleForMetadataCaching(beanName)) {
bd.stale = true;
}
});
}
private void clearByTypeCache() {
this.allBeanNamesByType.clear();
this.singletonBeanNamesByType.clear();
}
AbstractApplicationContext的invokeBeanFactoryPostProcessors
最后还要判断下是否要加入LoadTimeWeaverAwareProcessor处理器，这个暂时不重要。
protected void invokeBeanFactoryPostProcessors(ConfigurableListableBeanFactory beanFactory) {
PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(beanFactory, getBeanFactoryPostProcessors());
// Detect a LoadTimeWeaver and prepare for weaving, if found in the meantime
// (e.g. through an @Bean method registered by ConfigurationClassPostProcessor)
if (beanFactory.getTempClassLoader() == null && beanFactory.containsBean(LOAD_TIME_WEAVER_BEAN_NAME)) {
beanFactory.addBeanPostProcessor(new LoadTimeWeaverAwareProcessor(beanFactory));
beanFactory.setTempClassLoader(new ContextTypeMatchClassLoader(beanFactory.getBeanClassLoader()));
}
}
总结
至此调用BeanFactory的后置处理器全部完成了，我们来总结下，除去自定义的处理器，主要还是ConfigurationClassPostProcessor在处理，解析配置类，加载bean定义，配置类可能会进行CGLIB动态代理增强，最后把剩下的BeanFactoryPostProcessor处理器处理完：
后面就要进行BeanPostProcessor后置处理器注册啦，这个就是用来参与bean创建的过程啦。
registerBeanPostProcessors注册bean后置处理器
其实这个里面跟invokeBeanFactoryPostProcessors差不多，都是有优先级别处理的，然后会进行排序注册，最后就是这样的：
好了，今天就到这里了，希望对学习理解有帮助，大神看见勿喷，仅为自己的学习理解，能力有限，请多包涵。