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类图

负责解析处理所有@Configuration标签类，主要流程在ConfigurationClassParser中进行

postProcessBeanDefinitionRegistry

public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) {    processConfigBeanDefinitions(registry);}

processConfigBeanDefinitions

处理full和lite

先得到Spring内置的Bean定义和AnnotationConfigApplicationContext传进来的@Configuration

String[] candidateNames = registry.getBeanDefinitionNames(); // 目前都是spring内置的bean定义和 AnnotationConfigApplicationContext构造传进来的annotatedClassesfor (String beanName : candidateNames) {	BeanDefinition beanDef = registry.getBeanDefinition(beanName);	if (ConfigurationClassUtils.isFullConfigurationClass(beanDef) ||			ConfigurationClassUtils.isLiteConfigurationClass(beanDef)) { // 已经处理过了 full 、lite 已经标记打进去了		if (logger.isDebugEnabled()) {			logger.debug("Bean definition has already been processed as a configuration class: " + beanDef);		}	}	else if (ConfigurationClassUtils.checkConfigurationClassCandidate(beanDef, this.metadataReaderFactory)) { // 这里会处理full 、lite  如果2个都不是 返回false 有1个则返回true		configCandidates.add(new BeanDefinitionHolder(beanDef, beanName));	}}

这里最终得到的configCandidates，就是传进来的annotatedClasses

循环遍历解析configCandidates

// ConfigurationClassParserpublic void parse(Set
   
     configCandidates) {	for (BeanDefinitionHolder holder : configCandidates) { // 循环遍历configCandidates		BeanDefinition bd = holder.getBeanDefinition();		try {			if (bd instanceof AnnotatedBeanDefinition) {				parse(((AnnotatedBeanDefinition) bd).getMetadata(), holder.getBeanName()); // 注解的进入这里			}			else if (bd instanceof AbstractBeanDefinition && ((AbstractBeanDefinition) bd).hasBeanClass()) {				parse(((AbstractBeanDefinition) bd).getBeanClass(), holder.getBeanName());			}			else {				parse(bd.getBeanClassName(), holder.getBeanName());			}		}	}	this.deferredImportSelectorHandler.process();}
   

checkConfigurationClassCandidate

// 如果是@Configuration 会设置fullif (isFullConfigurationCandidate(metadata)) {	beanDef.setAttribute(CONFIGURATION_CLASS_ATTRIBUTE, CONFIGURATION_CLASS_FULL);}else if (isLiteConfigurationCandidate(metadata)) {	beanDef.setAttribute(CONFIGURATION_CLASS_ATTRIBUTE, CONFIGURATION_CLASS_LITE);}else {	return false;}// It's a full or lite configuration candidate... Let's determine the order value, if any.Integer order = getOrder(metadata);if (order != null) {	beanDef.setAttribute(ORDER_ATTRIBUTE, order);}return true;

postProcessBeanFactory

public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) {		int factoryId = System.identityHashCode(beanFactory);	if (this.factoriesPostProcessed.contains(factoryId)) {		throw new IllegalStateException(				"postProcessBeanFactory already called on this post-processor against " + beanFactory);	}	this.factoriesPostProcessed.add(factoryId);	if (!this.registriesPostProcessed.contains(factoryId)) {		// BeanDefinitionRegistryPostProcessor hook apparently not supported...		// Simply call processConfigurationClasses lazily at this point then.		processConfigBeanDefinitions((BeanDefinitionRegistry) beanFactory);	}	enhanceConfigurationClasses(beanFactory); //对标记@Configuration注解的类 会cblig增强	beanFactory.addBeanPostProcessor(new ImportAwareBeanPostProcessor(beanFactory)); // 添加ImportAwareBeanPostProcessor}

isFullConfigurationClass

public static boolean isFullConfigurationClass(BeanDefinition beanDef) {		return CONFIGURATION_CLASS_FULL.equals(beanDef.getAttribute(CONFIGURATION_CLASS_ATTRIBUTE));}

ConfigurationClassUtils

判断是否有Configuration注解

public static boolean isFullConfigurationCandidate(AnnotationMetadata metadata) {	return metadata.isAnnotated(Configuration.class.getName());}

如果存在Configuration，则设置CONFIGURATION_CLASS_ATTRIBUTE属性为full

if (isFullConfigurationCandidate(metadata)) {	beanDef.setAttribute(CONFIGURATION_CLASS_ATTRIBUTE, CONFIGURATION_CLASS_FULL);}

public void setAttribute(String name, @Nullable Object value) {	super.setAttribute(name, new BeanMetadataAttribute(name, value));}

isLiteConfigurationCandidate

会判断是否存在下面4个注解中的1个，存在，则返回true

candidateIndicators.add(Component.class.getName());candidateIndicators.add(ComponentScan.class.getName());candidateIndicators.add(Import.class.getName());candidateIndicators.add(ImportResource.class.getName());

如果上面4个注解，都不存在，则判断是否存在Bean注解

return metadata.hasAnnotatedMethods(Bean.class.getName());

也就是存在上面5个中的1个，就返回true，否则返回false

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