DefaultSingletonBeanRegistry (spring-beans 5.0.15.BUILD-SNAPSHOT API)

java.lang.Object
- org.springframework.core.SimpleAliasRegistry
- - org.springframework.beans.factory.support.DefaultSingletonBeanRegistry

所有已实现的接口:

SingletonBeanRegistry, org.springframework.core.AliasRegistry

直接已知子类:

FactoryBeanRegistrySupport
```
public class DefaultSingletonBeanRegistry
extends org.springframework.core.SimpleAliasRegistry
implements SingletonBeanRegistry
```
Generic registry for shared bean instances, implementing the SingletonBeanRegistry. Allows for registering singleton instances that should be shared for all callers of the registry, to be obtained via bean name.
Also supports registration of DisposableBean instances, (which might or might not correspond to registered singletons), to be destroyed on shutdown of the registry. Dependencies between beans can be registered to enforce an appropriate shutdown order.
This class mainly serves as base class for BeanFactory implementations, factoring out the common management of singleton bean instances. Note that the ConfigurableBeanFactory interface extends the SingletonBeanRegistry interface.
Note that this class assumes neither a bean definition concept nor a specific creation process for bean instances, in contrast to AbstractBeanFactory and DefaultListableBeanFactory (which inherit from it). Can alternatively also be used as a nested helper to delegate to.

从以下版本开始:

2.0

作者:

Juergen Hoeller

另请参阅:

registerSingleton(java.lang.String, java.lang.Object), registerDisposableBean(java.lang.String, org.springframework.beans.factory.DisposableBean), DisposableBean, ConfigurableBeanFactory

字段概要
- 从类继承的字段 org.springframework.core.SimpleAliasRegistry
  logger

构造器概要

构造器
构造器和说明

DefaultSingletonBeanRegistry()

构造器
构造器和说明
`DefaultSingletonBeanRegistry()`

方法概要

所有方法实例方法具体方法
限定符和类型	方法和说明
`protected void`	`addSingleton(String beanName, Object singletonObject)` 把对象加入到单例缓存池中(所谓的一级缓存并且考虑循环依赖和正常情况下,移除二三级缓存)
`protected void`	`addSingletonFactory(String beanName, ObjectFactory<?> singletonFactory)` 该方法用于把早期对象包装成一个ObjectFactory 暴露到三级缓存中用于将解决循环依赖...
`protected void`	`afterSingletonCreation(String beanName)` Callback after singleton creation.
`protected void`	`beforeSingletonCreation(String beanName)` Callback before singleton creation.
`protected void`	`clearSingletonCache()` Clear all cached singleton instances in this registry.
`boolean`	`containsSingleton(String beanName)` Check if this registry contains a singleton instance with the given name.
`protected void`	`destroyBean(String beanName, DisposableBean bean)` 销毁bean的依赖关系
`void`	`destroySingleton(String beanName)` 发生移除，销毁当前bean的所有信息
`void`	`destroySingletons()`
`String[]`	`getDependenciesForBean(String beanName)` Return the names of all beans that the specified bean depends on, if any.
`String[]`	`getDependentBeans(String beanName)` Return the names of all beans which depend on the specified bean, if any.
`Object`	`getSingleton(String beanName)` 该方法是一个空壳方法
`protected Object`	`getSingleton(String beanName, boolean allowEarlyReference)` 在网上很多很多写源码的大佬或者是一书上,也没有说清楚为啥要使用三级缓存(二级缓存可不可以能够解决) 答案是：可以, 但是没有很好的扩展性为啥这么说.......
`Object`	`getSingleton(String beanName, ObjectFactory<?> singletonFactory)` 获取单例对象(该流程用于触发构建bean)
`int`	`getSingletonCount()` Return the number of singleton beans registered in this registry.
`Object`	`getSingletonMutex()` Exposes the singleton mutex to subclasses and external collaborators.
`String[]`	`getSingletonNames()` Return the names of singleton beans registered in this registry.
`protected boolean`	`hasDependentBean(String beanName)` Determine whether a dependent bean has been registered for the given name.
`protected boolean`	`isActuallyInCreation(String beanName)`
`boolean`	`isCurrentlyInCreation(String beanName)`
`protected boolean`	`isDependent(String beanName, String dependentBeanName)` Determine whether the specified dependent bean has been registered as dependent on the given bean or on any of its transitive dependencies.
`boolean`	`isSingletonCurrentlyInCreation(String beanName)` Return whether the specified singleton bean is currently in creation (within the entire factory).
`protected void`	`onSuppressedException(Exception ex)` Register an Exception that happened to get suppressed during the creation of a singleton bean instance, e.g. a temporary circular reference resolution problem.
`void`	`registerContainedBean(String containedBeanName, String containingBeanName)` Register a containment relationship between two beans, e.g. between an inner bean and its containing outer bean.
`void`	`registerDependentBean(String beanName, String dependentBeanName)` 注册bean之间的依赖关系 to be destroyed before the given bean is destroyed.
`void`	`registerDisposableBean(String beanName, DisposableBean bean)` Add the given bean to the list of disposable beans in this registry.
`void`	`registerSingleton(String beanName, Object singletonObject)` Register the given existing object as singleton in the bean registry, under the given bean name.
`protected void`	`removeSingleton(String beanName)` Remove the bean with the given name from the singleton cache of this factory, to be able to clean up eager registration of a singleton if creation failed.
`void`	`setCurrentlyInCreation(String beanName, boolean inCreation)`

从类继承的方法 org.springframework.core.SimpleAliasRegistry
allowAliasOverriding, canonicalName, checkForAliasCircle, getAliases, hasAlias, isAlias, registerAlias, removeAlias, resolveAliases

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- 构造器详细资料
  - DefaultSingletonBeanRegistry
```
public DefaultSingletonBeanRegistry()
```
- 方法详细资料
  - registerSingleton
```
public void registerSingleton(String beanName,
                              Object singletonObject)
                       throws IllegalStateException
```
    从接口复制的说明: SingletonBeanRegistry
    
    Register the given existing object as singleton in the bean registry, under the given bean name.
    The given instance is supposed to be fully initialized; the registry will not perform any initialization callbacks (in particular, it won't call InitializingBean's afterPropertiesSet method). The given instance will not receive any destruction callbacks (like DisposableBean's destroy method) either.
    When running within a full BeanFactory: Register a bean definition instead of an existing instance if your bean is supposed to receive initialization and/or destruction callbacks.
    Typically invoked during registry configuration, but can also be used for runtime registration of singletons. As a consequence, a registry implementation should synchronize singleton access; it will have to do this anyway if it supports a BeanFactory's lazy initialization of singletons.
    
    指定者:
    
    registerSingleton 在接口中 SingletonBeanRegistry
    
    参数:
    
    beanName - the name of the bean
    
    singletonObject - the existing singleton object
    
    抛出:
    
    IllegalStateException
    
    另请参阅:
    
    InitializingBean.afterPropertiesSet(), DisposableBean.destroy(), BeanDefinitionRegistry.registerBeanDefinition(java.lang.String, org.springframework.beans.factory.config.BeanDefinition)
  - addSingleton
```
protected void addSingleton(String beanName,
                            Object singletonObject)
```
    把对象加入到单例缓存池中(所谓的一级缓存并且考虑循环依赖和正常情况下,移除二三级缓存)
    
    参数:
    
    beanName - bean的名称
    
    singletonObject - 创建出来的单实例bean
  - addSingletonFactory
```
protected void addSingletonFactory(String beanName,
                                   ObjectFactory<?> singletonFactory)
```
    该方法用于把早期对象包装成一个ObjectFactory 暴露到三级缓存中用于将解决循环依赖...
    
    参数:
    
    beanName - the name of the bean
    
    singletonFactory - the factory for the singleton object
  - getSingleton
```
@Nullable
public Object getSingleton(String beanName)
```
    该方法是一个空壳方法
    
    指定者:
    
    getSingleton 在接口中 SingletonBeanRegistry
    
    参数:
    
    beanName - bean的名称
    
    返回:
    
    缓存中的对象(有可能是一个单例完整对象,也有可能是一个早期对象(用于解决循环依赖))
    
    另请参阅:
    
    ConfigurableListableBeanFactory.getBeanDefinition(java.lang.String)
  - getSingleton
```
@Nullable
protected Object getSingleton(String beanName,
                                         boolean allowEarlyReference)
```
    在网上很多很多写源码的大佬或者是一书上,也没有说清楚为啥要使用三级缓存(二级缓存可不可以能够解决) 答案是：可以, 但是没有很好的扩展性为啥这么说....... 原因: 获取三级缓存-----getEarlyBeanReference()经过一系列的后置处理来给我们早期对象进行特殊化处理 //从三级缓存中获取包装对象的时候，他会经过一次后置处理器的处理对我们早期对象的bean进行特殊化处理，但是spring的原生后置处理器没有经过处理，而是留给了我们程序员进行扩展 singletonObject = singletonFactory.getObject(); 把三级缓存移植到二级缓存中 this.earlySingletonObjects.put(beanName, singletonObject); //删除三级缓存中的之 this.singletonFactories.remove(beanName);
    
    参数:
    
    beanName - bean的名称
    
    allowEarlyReference - 是否允许暴露早期对象通过该参数可以控制是否能够解决循环依赖的.
    
    返回:
    
    这里可能返回一个null（IOC容器加载单实例bean的时候,第一次进来是返回null）也有可能返回一个单例对象(IOC容器加载了单实例了,第二次来获取当前的Bean) 也可能返回一个早期对象(用于解决循环依赖问题)
  - getSingleton
```
public Object getSingleton(String beanName,
                           ObjectFactory<?> singletonFactory)
```
    获取单例对象(该流程用于触发构建bean)
    
    参数:
    
    beanName - the name of the bean
    
    singletonFactory - the ObjectFactory to lazily create the singleton with, if necessary
    
    返回:
    
    the registered singleton object
  - onSuppressedException
```
protected void onSuppressedException(Exception ex)
```
    Register an Exception that happened to get suppressed during the creation of a singleton bean instance, e.g. a temporary circular reference resolution problem.
    
    参数:
    
    ex - the Exception to register
  - removeSingleton
```
protected void removeSingleton(String beanName)
```
    Remove the bean with the given name from the singleton cache of this factory, to be able to clean up eager registration of a singleton if creation failed.
    
    参数:
    
    beanName - the name of the bean
    
    另请参阅:
    
    getSingletonMutex()
  - containsSingleton
```
public boolean containsSingleton(String beanName)
```
    从接口复制的说明: SingletonBeanRegistry
    
    Check if this registry contains a singleton instance with the given name.
    Only checks already instantiated singletons; does not return true for singleton bean definitions which have not been instantiated yet.
    The main purpose of this method is to check manually registered singletons (see SingletonBeanRegistry.registerSingleton(java.lang.String, java.lang.Object)). Can also be used to check whether a singleton defined by a bean definition has already been created.
    To check whether a bean factory contains a bean definition with a given name, use ListableBeanFactory's containsBeanDefinition. Calling both containsBeanDefinition and containsSingleton answers whether a specific bean factory contains a local bean instance with the given name.
    Use BeanFactory's containsBean for general checks whether the factory knows about a bean with a given name (whether manually registered singleton instance or created by bean definition), also checking ancestor factories.
    NOTE: This lookup method is not aware of FactoryBean prefixes or aliases. You need to resolve the canonical bean name first before checking the singleton status.
    
    指定者:
    
    containsSingleton 在接口中 SingletonBeanRegistry
    
    参数:
    
    beanName - the name of the bean to look for
    
    返回:
    
    if this bean factory contains a singleton instance with the given name
    
    另请参阅:
    
    SingletonBeanRegistry.registerSingleton(java.lang.String, java.lang.Object), ListableBeanFactory.containsBeanDefinition(java.lang.String), BeanFactory.containsBean(java.lang.String)
  - getSingletonNames
```
public String[] getSingletonNames()
```
    从接口复制的说明: SingletonBeanRegistry
    
    Return the names of singleton beans registered in this registry.
    Only checks already instantiated singletons; does not return names for singleton bean definitions which have not been instantiated yet.
    The main purpose of this method is to check manually registered singletons (see SingletonBeanRegistry.registerSingleton(java.lang.String, java.lang.Object)). Can also be used to check which singletons defined by a bean definition have already been created.
    
    指定者:
    
    getSingletonNames 在接口中 SingletonBeanRegistry
    
    返回:
    
    the list of names as a String array (never null)
    
    另请参阅:
    
    SingletonBeanRegistry.registerSingleton(java.lang.String, java.lang.Object), BeanDefinitionRegistry.getBeanDefinitionNames(), ListableBeanFactory.getBeanDefinitionNames()
  - getSingletonCount
```
public int getSingletonCount()
```
    从接口复制的说明: SingletonBeanRegistry
    
    Return the number of singleton beans registered in this registry.
    Only checks already instantiated singletons; does not count singleton bean definitions which have not been instantiated yet.
    The main purpose of this method is to check manually registered singletons (see SingletonBeanRegistry.registerSingleton(java.lang.String, java.lang.Object)). Can also be used to count the number of singletons defined by a bean definition that have already been created.
    
    指定者:
    
    getSingletonCount 在接口中 SingletonBeanRegistry
    
    返回:
    
    the number of singleton beans
    
    另请参阅:
    
    SingletonBeanRegistry.registerSingleton(java.lang.String, java.lang.Object), BeanDefinitionRegistry.getBeanDefinitionCount(), ListableBeanFactory.getBeanDefinitionCount()
  - setCurrentlyInCreation
```
public void setCurrentlyInCreation(String beanName,
                                   boolean inCreation)
```
  - isCurrentlyInCreation
```
public boolean isCurrentlyInCreation(String beanName)
```
  - isActuallyInCreation
```
protected boolean isActuallyInCreation(String beanName)
```
  - isSingletonCurrentlyInCreation
```
public boolean isSingletonCurrentlyInCreation(String beanName)
```
    Return whether the specified singleton bean is currently in creation (within the entire factory).
    
    参数:
    
    beanName - the name of the bean
  - beforeSingletonCreation
```
protected void beforeSingletonCreation(String beanName)
```
    Callback before singleton creation.
    The default implementation register the singleton as currently in creation.
    
    参数:
    
    beanName - the name of the singleton about to be created
    
    另请参阅:
    
    isSingletonCurrentlyInCreation(java.lang.String)
  - afterSingletonCreation
```
protected void afterSingletonCreation(String beanName)
```
    Callback after singleton creation.
    The default implementation marks the singleton as not in creation anymore.
    
    参数:
    
    beanName - the name of the singleton that has been created
    
    另请参阅:
    
    isSingletonCurrentlyInCreation(java.lang.String)
  - registerDisposableBean
```
public void registerDisposableBean(String beanName,
                                   DisposableBean bean)
```
    Add the given bean to the list of disposable beans in this registry.
    Disposable beans usually correspond to registered singletons, matching the bean name but potentially being a different instance (for example, a DisposableBean adapter for a singleton that does not naturally implement Spring's DisposableBean interface).
    
    参数:
    
    beanName - the name of the bean
    
    bean - the bean instance
  - registerContainedBean
```
public void registerContainedBean(String containedBeanName,
                                  String containingBeanName)
```
    Register a containment relationship between two beans, e.g. between an inner bean and its containing outer bean.
    Also registers the containing bean as dependent on the contained bean in terms of destruction order.
    
    参数:
    
    containedBeanName - the name of the contained (inner) bean
    
    containingBeanName - the name of the containing (outer) bean
    
    另请参阅:
    
    registerDependentBean(java.lang.String, java.lang.String)
  - registerDependentBean
```
public void registerDependentBean(String beanName,
                                  String dependentBeanName)
```
    注册bean之间的依赖关系 to be destroyed before the given bean is destroyed.
    
    参数:
    
    beanName - the name of the bean
    
    dependentBeanName - the name of the dependent bean
  - isDependent
```
protected boolean isDependent(String beanName,
                              String dependentBeanName)
```
    Determine whether the specified dependent bean has been registered as dependent on the given bean or on any of its transitive dependencies.
    
    参数:
    
    beanName - the name of the bean to check
    
    dependentBeanName - the name of the dependent bean
    
    从以下版本开始:
    
    4.0
  - hasDependentBean
```
protected boolean hasDependentBean(String beanName)
```
    Determine whether a dependent bean has been registered for the given name.
    
    参数:
    
    beanName - the name of the bean to check
  - getDependentBeans
```
public String[] getDependentBeans(String beanName)
```
    Return the names of all beans which depend on the specified bean, if any.
    
    参数:
    
    beanName - the name of the bean
    
    返回:
    
    the array of dependent bean names, or an empty array if none
  - getDependenciesForBean
```
public String[] getDependenciesForBean(String beanName)
```
    Return the names of all beans that the specified bean depends on, if any.
    
    参数:
    
    beanName - the name of the bean
    
    返回:
    
    the array of names of beans which the bean depends on, or an empty array if none
  - destroySingletons
```
public void destroySingletons()
```
  - clearSingletonCache
```
protected void clearSingletonCache()
```
    Clear all cached singleton instances in this registry.
    
    从以下版本开始:
    
    4.3.15
  - destroySingleton
```
public void destroySingleton(String beanName)
```
    发生移除，销毁当前bean的所有信息
    
    参数:
    
    beanName - bean的名称
    
    另请参阅:
    
    destroyBean(java.lang.String, org.springframework.beans.factory.DisposableBean)
  - destroyBean
```
protected void destroyBean(String beanName,
                           @Nullable
                           DisposableBean bean)
```
    销毁bean的依赖关系
    
    参数:
    
    beanName - the name of the bean
    
    bean - the bean instance to destroy
  - getSingletonMutex
```
public final Object getSingletonMutex()
```
    Exposes the singleton mutex to subclasses and external collaborators.
    Subclasses should synchronize on the given Object if they perform any sort of extended singleton creation phase. In particular, subclasses should not have their own mutexes involved in singleton creation, to avoid the potential for deadlocks in lazy-init situations.
    
    指定者:
    
    getSingletonMutex 在接口中 SingletonBeanRegistry
    
    返回:
    
    the mutex object (never null)

类 DefaultSingletonBeanRegistry

字段概要

从类继承的字段 org.springframework.core.SimpleAliasRegistry

构造器概要

方法概要

从类继承的方法 org.springframework.core.SimpleAliasRegistry

从类继承的方法 java.lang.Object

构造器详细资料

DefaultSingletonBeanRegistry

方法详细资料

registerSingleton

addSingleton

addSingletonFactory

getSingleton

getSingleton

getSingleton

onSuppressedException

removeSingleton

containsSingleton

getSingletonNames

getSingletonCount

setCurrentlyInCreation

isCurrentlyInCreation

isActuallyInCreation

isSingletonCurrentlyInCreation

beforeSingletonCreation

afterSingletonCreation

registerDisposableBean

registerContainedBean

registerDependentBean

isDependent

hasDependentBean

getDependentBeans

getDependenciesForBean

destroySingletons

clearSingletonCache

destroySingleton

destroyBean

getSingletonMutex