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咱们直接看一下AbstractBeanFactory的继承和实现结构:

大体描述一下:AbstractBeanFactory功能结构主要有两部分,1.实现了BeanFactory相关的功能,2.实现了别名,单列注册以及工厂支持. BeanFactory相关接口前面已经描述过,这里不再重复,接下来看一下2)部分: 1.AliasRegistry别名注册

//给指定的bean注册别名	void registerAlias(String name, String alias);	//移除别名	void removeAlias(String alias);	//别名判断	boolean isAlias(String name);	//获取所有的别名	String[] getAliases(String name);

2.SimpleAliasRegistry别名注册的简单实现类,核心结构如下:

//别名map,键是别名,值是name	private final Map
   
     aliasMap = new ConcurrentHashMap<>(16);
   

3.SingletonBeanRegistry单例bean注册支持

void registerSingleton(String beanName, Object singletonObject);	Object getSingleton(String beanName);	boolean containsSingleton(String beanName);	String[] getSingletonNames();	int getSingletonCount();	//注册单例的锁,同步对单例结构的更改	Object getSingletonMutex();

4.DefaultSingletonBeanRegistry对单列注册的结构性实现

看一下核心结构:

/** Cache of singleton objects: bean name to bean instance. */所有的单列都存储在这个map中	private final Map
   
     singletonObjects = new ConcurrentHashMap<>(256);	/** Cache of singleton factories: bean name to ObjectFactory. */单列对象的创建工厂	private final Map
    
     > singletonFactories = new HashMap<>(16);	/** Cache of early singleton objects: bean name to bean instance. */正在创建中的bean	private final Map
     
       earlySingletonObjects = new HashMap<>(16);	/** Set of registered singletons, containing the bean names in registration order. */按注册顺序的所有注册beanname的集合	private final Set
      
        registeredSingletons = new LinkedHashSet<>(256);	/** Names of beans that are currently in creation. */当前正在创建中的bean	private final Set
       
         singletonsCurrentlyInCreation =			Collections.newSetFromMap(new ConcurrentHashMap<>(16));	/** Names of beans currently excluded from in creation checks. */排除在创建检查之外的beanname	private final Set
        
          inCreationCheckExclusions = Collections.newSetFromMap(new ConcurrentHashMap<>(16)); /** List of suppressed Exceptions, available for associating related causes. */ @Nullable private Set
         
           suppressedExceptions; /** Flag that indicates whether we're currently within destroySingletons. */ private boolean singletonsCurrentlyInDestruction = false; /** Disposable bean instances: bean name to disposable instance. */需要执行destroy接口的bean的map private final Map
          
            disposableBeans = new LinkedHashMap<>(); /** Map between containing bean names: bean name to Set of bean names that the bean contains. */描述了bean和内部bean之间关系 private final Map
           
            > containedBeanMap = new ConcurrentHashMap<>(16); /** Map between dependent bean names: bean name to Set of dependent bean names. */描述了当前bean被那些bean依赖的关系 private final Map
            
             > dependentBeanMap = new ConcurrentHashMap<>(64); /** Map between depending bean names: bean name to Set of bean names for the bean's dependencies. */描述了bean和依赖bean之间的关系 private final Map
             
              > dependenciesForBeanMap = new ConcurrentHashMap<>(64);
             
            
           
          
         
        
       
      
     
    
   

5.FactoryBeanRegistrySupport工厂支持bean

看一下核心结构:

/** Cache of singleton objects created by FactoryBeans: FactoryBean name to object. */private final Map
   
     factoryBeanObjectCache = new ConcurrentHashMap<>(16);
   

6.AbstractBeanFactory第一个带有BeanFactory结尾的抽象类,基本成型,先来了解一下他的核心结构:

/** Parent bean factory, for bean inheritance support. */垂直工程结构的支持	@Nullable	private BeanFactory parentBeanFactory;	/** ClassLoader to resolve bean class names with, if necessary. */类加载器	@Nullable	private ClassLoader beanClassLoader = ClassUtils.getDefaultClassLoader();	/** ClassLoader to temporarily resolve bean class names with, if necessary. */一般在lwt中使用	@Nullable	private ClassLoader tempClassLoader;	/** Whether to cache bean metadata or rather reobtain it for every access. */是否缓存bean的元数据,不缓存的话每次创建bean都会重新加载bean的定义	private boolean cacheBeanMetadata = true;	/** Resolution strategy for expressions in bean definition values. */表达式解析spel	@Nullable	private BeanExpressionResolver beanExpressionResolver;	/** Spring ConversionService to use instead of PropertyEditors. */类型安全转换服务	@Nullable	private ConversionService conversionService;	/** Custom PropertyEditorRegistrars to apply to the beans of this factory. */属性注册	private final Set
   
     propertyEditorRegistrars = new LinkedHashSet<>(4);	/** Custom PropertyEditors to apply to the beans of this factory. */定制的属性编辑器	private final Map
    
     , Class
     > customEditors = new HashMap<>(4);	/** A custom TypeConverter to use, overriding the default PropertyEditor mechanism. */类型转换	@Nullable	private TypeConverter typeConverter;	/** String resolvers to apply e.g. to annotation attribute values. */值解析	private final List
     
       embeddedValueResolvers = new CopyOnWriteArrayList<>();	/** BeanPostProcessors to apply in createBean. */各种BeanPostProcessor集合	private final List
      
        beanPostProcessors = new CopyOnWriteArrayList<>();	/** Indicates whether any InstantiationAwareBeanPostProcessors have been registered. */是否有实例化BeanPost后置处理器	private volatile boolean hasInstantiationAwareBeanPostProcessors;	/** Indicates whether any DestructionAwareBeanPostProcessors have been registered. */是否有DestructionAwareBeanPostProcessors 后置处理器	private volatile boolean hasDestructionAwareBeanPostProcessors;	/** Map from scope identifier String to corresponding Scope. */各种scope	private final Map
       
         scopes = new LinkedHashMap<>(8);	/** Security context used when running with a SecurityManager. */	@Nullable	private SecurityContextProvider securityContextProvider;	/** Map from bean name to merged RootBeanDefinition. */合并后的bean定义map	private final Map
        
          mergedBeanDefinitions = new ConcurrentHashMap<>(256); /** Names of beans that have already been created at least once. */已经创建的bean的合集 private final Set
         
           alreadyCreated = Collections.newSetFromMap(new ConcurrentHashMap<>(256)); /** Names of beans that are currently in creation. */正在创建的原型 private final ThreadLocal
          
         
        
       
      
     
    
   

7.AutowireCapableBeanFactory可注入bean工厂

   
     T createBean(Class
    
      beanClass) throws BeansException;	void autowireBean(Object existingBean) throws BeansException;	Object configureBean(Object existingBean, String beanName) throws BeansException;	Object createBean(Class
      beanClass, int autowireMode, boolean dependencyCheck) throws BeansException;	Object autowire(Class
      beanClass, int autowireMode, boolean dependencyCheck) throws BeansException;	void autowireBeanProperties(Object existingBean, int autowireMode, boolean dependencyCheck)			throws BeansException;	void applyBeanPropertyValues(Object existingBean, String beanName) throws BeansException;	Object initializeBean(Object existingBean, String beanName) throws BeansException;	Object applyBeanPostProcessorsBeforeInitialization(Object existingBean, String beanName)			throws BeansException;	Object applyBeanPostProcessorsAfterInitialization(Object existingBean, String beanName)			throws BeansException;	void destroyBean(Object existingBean);	
     
       NamedBeanHolder
      
        resolveNamedBean(Class
       
         requiredType) throws BeansException;	Object resolveDependency(DependencyDescriptor descriptor, @Nullable String requestingBeanName) throws BeansException;	Object resolveDependency(DependencyDescriptor descriptor, @Nullable String requestingBeanName,			@Nullable Set
        
          autowiredBeanNames, @Nullable TypeConverter typeConverter) throws BeansException;}
        
       
      
     
    
   

讲一个bean工厂转换成,该结构后可以单独使用手动创建bean,自动注入字段等功能.

8.DefaultListableBeanFactory默认可枚举工厂,默认的ApplicationContext创建的就是这个对象,通过他可以

简单的描述一下他的结构:

/** Map from serialized id to factory instance. */	private static final Map
   
    > serializableFactories =			new ConcurrentHashMap<>(8);	/** Optional id for this factory, for serialization purposes. */	@Nullable	private String serializationId;	/** Whether to allow re-registration of a different definition with the same name. */	private boolean allowBeanDefinitionOverriding = true;	/** Whether to allow eager class loading even for lazy-init beans. */	private boolean allowEagerClassLoading = true;	/** Optional OrderComparator for dependency Lists and arrays. */	@Nullable	private Comparator
    
   

9.BeanDefinitionRegistry接口,所有的bean的定义都是通过这里的api注入到beanfactory中,常见的有解析xml配置或注解配置,然后注入到bean工厂中,看一下他的接口视图:

void registerBeanDefinition(String beanName, BeanDefinition beanDefinition)			throws BeanDefinitionStoreException;		void removeBeanDefinition(String beanName) throws NoSuchBeanDefinitionException;		BeanDefinition getBeanDefinition(String beanName) throws NoSuchBeanDefinitionException;		boolean containsBeanDefinition(String beanName);		String[] getBeanDefinitionNames();		int getBeanDefinitionCount();	boolean isBeanNameInUse(String beanName);

下一节,我们一起看一下ApplicationContext的结构,然后进行一些必要的实践,加深对运行过程中,各个结构如何协调工作,具体存储数据的视图.

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