对于想要拥有自动装配能力，并且想把这种能力暴露给外部应用的BeanFactory类需要实现此接口。
正常情况下，不要使用此接口，应该更倾向于使用BeanFactory或者ListableBeanFactory接口。此接口主要是针对框架之外，没有向Spring托管Bean的应用。通过暴露此功能，Spring框架之外的程序，具有自动装配等Spring的功能。
需要注意的是，ApplicationContext接口并没有实现此接口，因为应用代码很少用到此功能，如果确实需要的话，可以调用ApplicationContext的getAutowireCapableBeanFactory方法，来获取此接口的实例。
===================================以下中文版==================================================
如果一个类实现了此接口，那么很大程度上它还需要实现BeanFactoryAware接口。它可以在应用上下文中返回BeanFactory。
public interface AutowireCapableBeanFactory extends BeanFactory {
/**
* 常量，用于标识外部自动装配功能是否可用。但是此标识不影响正常的（基于注解的等）自动装配功能的使用
*/
int AUTOWIRE_NO = 0;
/**
* 标识按名装配的常量
*/
int AUTOWIRE_BY_NAME = 1;
/**
* 标识按类型自动装配的常量
*/
int AUTOWIRE_BY_TYPE = 2;
/**
* 标识按照贪婪策略匹配出的最符合的构造方法来自动装配的常量
*/
int AUTOWIRE_CONSTRUCTOR = 3;
/**
* 标识自动识别一种装配策略来实现自动装配的常量
*/
@Deprecated
int AUTOWIRE_AUTODETECT = 4;
/**
* 创建一个给定Class的实例。
* 执行此Bean所有的关于Bean生命周期的接口方法如BeanPostProcessor
* 此方法用于创建一个新实例，它会处理各种带有注解的域和方法，并且会调用所有Bean初始化时所需要调用的回调函数
* 此方法并不意味着by-name或者by-type方式的自动装配，如果需要使用这写功能，可以使用其重载方法
*/
<T> T createBean(Class<T> beanClass) throws BeansException;
/**
* Populate the given bean instance through applying after-instantiation callbacks
* 通过调用给定Bean的after-instantiation及post-processing接口，对bean进行配置。
* 此方法主要是用于处理Bean中带有注解的域和方法。
* 此方法并不意味着by-name或者by-type方式的自动装配，如果需要使用这写功能，可以使用其重载方法autowireBeanProperties
*/
void autowireBean(Object existingBean) throws BeansException;
/**
* Configure the given raw bean: autowiring bean properties, applying
* 配置参数中指定的bean，包括自动装配其域，对其应用如setBeanName功能的回调函数。
* 并且会调用其所有注册的post processor.
* 此方法提供的功能是initializeBean方法的超集，会应用所有注册在bean definenition中的操作。
* 不过需要BeanFactory 中有参数中指定名字的BeanDefinition。
*/
Object configureBean(Object existingBean, String beanName) throws BeansException;
/**
* 创建一个指定class的实例，通过参数可以指定其自动装配模式（by-name or by-type）.
* 会执行所有注册在此class上用以初始化bean的方法，如BeanPostProcessors等
*/
Object createBean(Class<?> beanClass, int autowireMode, boolean dependencyCheck) throws BeansException;
/**
* 通过指定的自动装配策略来初始化一个Bean。
* 此方法不会调用Bean上注册的诸如BeanPostProcessors的回调方法
*/
Object autowire(Class<?> beanClass, int autowireMode, boolean dependencyCheck) throws BeansException;
/**
* 通过指定的自动装配方式来对给定的Bean进行自动装配。
* 不过会调用指定Bean注册的BeanPostProcessors等回调函数来初始化Bean。
* 如果指定装配方式为AUTOWIRE_NO的话，不会自动装配属性，但是依然会调用BeanPiostProcesser等回调方法。
*/
void autowireBeanProperties(Object existingBean, int autowireMode, boolean dependencyCheck)
throws BeansException;
/**
* 将参数中指定了那么的Bean，注入给定实例当中
* 此方法不会自动注入Bean的属性，它仅仅会应用在显式定义的属性之上。如果需要自动注入Bean属性，使用
* autowireBeanProperties方法。
* 此方法需要BeanFactory中存在指定名字的Bean。除了InstantiationAwareBeanPostProcessor的回调方法外，
* 此方法不会在Bean上应用其它的例如BeanPostProcessors
* 等回调方法。不过可以调用其他诸如initializeBean等方法来达到目的。
*/
void applyBeanPropertyValues(Object existingBean, String beanName) throws BeansException;
/**
* 初始化参数中指定的Bean，调用任何其注册的回调函数如setBeanName、setBeanFactory等。
* 另外还会调用此Bean上的所有postProcessors 方法
*/
Object initializeBean(Object existingBean, String beanName) throws BeansException;
/**
* 调用参数中指定Bean的postProcessBeforeInitialization方法
*/
Object applyBeanPostProcessorsBeforeInitialization(Object existingBean, String beanName)
throws BeansException;
/**
* 调用参数中指定Bean的postProcessAfterInitialization方法
*/
Object applyBeanPostProcessorsAfterInitialization(Object existingBean, String beanName)
throws BeansException;
/**
* 销毁参数中指定的Bean，同时调用此Bean上的DisposableBean和DestructionAwareBeanPostProcessors方法
* 在销毁途中，任何的异常情况都只应该被直接捕获和记录，而不应该向外抛出。
*/
void destroyBean(Object existingBean);
/**
* 查找唯一符合指定类的实例，如果有，则返回实例的名字和实例本身
* 和BeanFactory中的getBean(Class)方法类似，只不过多加了一个bean的名字
*/
<T> NamedBeanHolder<T> resolveNamedBean(Class<T> requiredType) throws BeansException;
/**
* 解析出在Factory中与指定Bean有指定依赖关系的Bean
* 参数建下一个方法
*/
Object resolveDependency(DependencyDescriptor descriptor, String requestingBeanName) throws BeansException;
/**
* 解析指定Bean在Factory中的依赖关系
* @param descriptor 依赖描述 (field/method/constructor)
* @param requestingBeanName 依赖描述所属的Bean
* @param autowiredBeanNames 与指定Bean有依赖关系的Bean
* @param typeConverter 用以转换数组和连表的转换器
* @return the 解析结果，可能为null
*/
Object resolveDependency(DependencyDescriptor descriptor, String requestingBeanName,
Set<String> autowiredBeanNames, TypeConverter typeConverter) throws BeansException;
==========================以下英文版==================================
/*
* Copyright 2002-2013 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.beans.factory.config;
import java.util.Set;
import org.springframework.beans.BeansException;
import org.springframework.beans.TypeConverter;
import org.springframework.beans.factory.BeanFactory;
/**
* Extension of the {@link org.springframework.beans.factory.BeanFactory}
* interface to be implemented by bean factories that are capable of
* autowiring, provided that they want to expose this functionality for
* existing bean instances.
*
* <p>This subinterface of BeanFactory is not meant to be used in normal
* application code: stick to {@link org.springframework.beans.factory.BeanFactory}
* or {@link org.springframework.beans.factory.ListableBeanFactory} for
* typical use cases.
*
* <p>Integration code for other frameworks can leverage this interface to
* wire and populate existing bean instances that Spring does not control
* the lifecycle of. This is particularly useful for WebWork Actions and
* Tapestry Page objects, for example.
*
* <p>Note that this interface is not implemented by
* {@link org.springframework.context.ApplicationContext} facades,
* as it is hardly ever used by application code. That said, it is available
* from an application context too, accessible through ApplicationContext's
* {@link org.springframework.context.ApplicationContext#getAutowireCapableBeanFactory()}
* method.
*
* <p>You may also implement the {@link org.springframework.beans.factory.BeanFactoryAware}
* interface, which exposes the internal BeanFactory even when running in an
* ApplicationContext, to get access to an AutowireCapableBeanFactory:
* simply cast the passed-in BeanFactory to AutowireCapableBeanFactory.
*
* @author Juergen Hoeller
* @since 04.12.2003
* @see org.springframework.beans.factory.BeanFactoryAware
* @see org.springframework.beans.factory.config.ConfigurableListableBeanFactory
* @see org.springframework.context.ApplicationContext#getAutowireCapableBeanFactory()
*/
public interface AutowireCapableBeanFactory extends BeanFactory {
/**
* Constant that indicates no externally defined autowiring. Note that
* BeanFactoryAware etc and annotation-driven injection will still be applied.
* @see #createBean
* @see #autowire
* @see #autowireBeanProperties
*/
int AUTOWIRE_NO = 0;
/**
* Constant that indicates autowiring bean properties by name
* (applying to all bean property setters).
* @see #createBean
* @see #autowire
* @see #autowireBeanProperties
*/
int AUTOWIRE_BY_NAME = 1;
/**
* Constant that indicates autowiring bean properties by type
* (applying to all bean property setters).
* @see #createBean
* @see #autowire
* @see #autowireBeanProperties
*/
int AUTOWIRE_BY_TYPE = 2;
/**
* Constant that indicates autowiring the greediest constructor that
* can be satisfied (involves resolving the appropriate constructor).
* @see #createBean
* @see #autowire
*/
int AUTOWIRE_CONSTRUCTOR = 3;
/**
* Constant that indicates determining an appropriate autowire strategy
* through introspection of the bean class.
* @see #createBean
* @see #autowire
* @deprecated as of Spring 3.0: If you are using mixed autowiring strategies,
* prefer annotation-based autowiring for clearer demarcation of autowiring needs.
*/
@Deprecated
int AUTOWIRE_AUTODETECT = 4;
//-------------------------------------------------------------------------
// Typical methods for creating and populating external bean instances
//-------------------------------------------------------------------------
/**
* Fully create a new bean instance of the given class.
* <p>Performs full initialization of the bean, including all applicable
* {@link BeanPostProcessor BeanPostProcessors}.
* <p>Note: This is intended for creating a fresh instance, populating annotated
* fields and methods as well as applying all standard bean initialiation callbacks.
* It does <i>not</> imply traditional by-name or by-type autowiring of properties;
* use {@link #createBean(Class, int, boolean)} for that purposes.
* @param beanClass the class of the bean to create
* @return the new bean instance
* @throws BeansException if instantiation or wiring failed
*/
<T> T createBean(Class<T> beanClass) throws BeansException;
/**
* Populate the given bean instance through applying after-instantiation callbacks
* and bean property post-processing (e.g. for annotation-driven injection).
* <p>Note: This is essentially intended for (re-)populating annotated fields and
* methods, either for new instances or for deserialized instances. It does
* <i>not</i> imply traditional by-name or by-type autowiring of properties;
* use {@link #autowireBeanProperties} for that purposes.
* @param existingBean the existing bean instance
* @throws BeansException if wiring failed
*/
void autowireBean(Object existingBean) throws BeansException;
/**
* Configure the given raw bean: autowiring bean properties, applying
* bean property values, applying factory callbacks such as {@code setBeanName}
* and {@code setBeanFactory}, and also applying all bean post processors
* (including ones which might wrap the given raw bean).
* <p>This is effectively a superset of what {@link #initializeBean} provides,
* fully applying the configuration specified by the corresponding bean definition.
* <b>Note: This method requires a bean definition for the given name!</b>
* @param existingBean the existing bean instance
* @param beanName the name of the bean, to be passed to it if necessary
* (a bean definition of that name has to be available)
* @return the bean instance to use, either the original or a wrapped one
* @throws org.springframework.beans.factory.NoSuchBeanDefinitionException
* if there is no bean definition with the given name
* @throws BeansException if the initialization failed
* @see #initializeBean
*/
Object configureBean(Object existingBean, String beanName) throws BeansException;
/**
* Resolve the specified dependency against the beans defined in this factory.
* @param descriptor the descriptor for the dependency
* @param beanName the name of the bean which declares the present dependency
* @return the resolved object, or {@code null} if none found
* @throws BeansException in dependency resolution failed
*/
Object resolveDependency(DependencyDescriptor descriptor, String beanName) throws BeansException;
//-------------------------------------------------------------------------
// Specialized methods for fine-grained control over the bean lifecycle
//-------------------------------------------------------------------------
/**
* Fully create a new bean instance of the given class with the specified
* autowire strategy. All constants defined in this interface are supported here.
* <p>Performs full initialization of the bean, including all applicable
* {@link BeanPostProcessor BeanPostProcessors}. This is effectively a superset
* of what {@link #autowire} provides, adding {@link #initializeBean} behavior.
* @param beanClass the class of the bean to create
* @param autowireMode by name or type, using the constants in this interface
* @param dependencyCheck whether to perform a dependency check for objects
* (not applicable to autowiring a constructor, thus ignored there)
* @return the new bean instance
* @throws BeansException if instantiation or wiring failed
* @see #AUTOWIRE_NO
* @see #AUTOWIRE_BY_NAME
* @see #AUTOWIRE_BY_TYPE
* @see #AUTOWIRE_CONSTRUCTOR
*/
Object createBean(Class<?> beanClass, int autowireMode, boolean dependencyCheck) throws BeansException;
/**
* Instantiate a new bean instance of the given class with the specified autowire
* strategy. All constants defined in this interface are supported here.
* Can also be invoked with {@code AUTOWIRE_NO} in order to just apply
* before-instantiation callbacks (e.g. for annotation-driven injection).
* <p>Does <i>not</i> apply standard {@link BeanPostProcessor BeanPostProcessors}
* callbacks or perform any further initialization of the bean. This interface
* offers distinct, fine-grained operations for those purposes, for example
* {@link #initializeBean}. However, {@link InstantiationAwareBeanPostProcessor}
* callbacks are applied, if applicable to the construction of the instance.
* @param beanClass the class of the bean to instantiate
* @param autowireMode by name or type, using the constants in this interface
* @param dependencyCheck whether to perform a dependency check for object
* references in the bean instance (not applicable to autowiring a constructor,
* thus ignored there)
* @return the new bean instance
* @throws BeansException if instantiation or wiring failed
* @see #AUTOWIRE_NO
* @see #AUTOWIRE_BY_NAME
* @see #AUTOWIRE_BY_TYPE
* @see #AUTOWIRE_CONSTRUCTOR
* @see #AUTOWIRE_AUTODETECT
* @see #initializeBean
* @see #applyBeanPostProcessorsBeforeInitialization
* @see #applyBeanPostProcessorsAfterInitialization
*/
Object autowire(Class<?> beanClass, int autowireMode, boolean dependencyCheck) throws BeansException;
/**
* Autowire the bean properties of the given bean instance by name or type.
* Can also be invoked with {@code AUTOWIRE_NO} in order to just apply
* after-instantiation callbacks (e.g. for annotation-driven injection).
* <p>Does <i>not</i> apply standard {@link BeanPostProcessor BeanPostProcessors}
* callbacks or perform any further initialization of the bean. This interface
* offers distinct, fine-grained operations for those purposes, for example
* {@link #initializeBean}. However, {@link InstantiationAwareBeanPostProcessor}
* callbacks are applied, if applicable to the configuration of the instance.
* @param existingBean the existing bean instance
* @param autowireMode by name or type, using the constants in this interface
* @param dependencyCheck whether to perform a dependency check for object
* references in the bean instance
* @throws BeansException if wiring failed
* @see #AUTOWIRE_BY_NAME
* @see #AUTOWIRE_BY_TYPE
* @see #AUTOWIRE_NO
*/
void autowireBeanProperties(Object existingBean, int autowireMode, boolean dependencyCheck)
throws BeansException;
/**
* Apply the property values of the bean definition with the given name to
* the given bean instance. The bean definition can either define a fully
* self-contained bean, reusing its property values, or just property values
* meant to be used for existing bean instances.
* <p>This method does <i>not</i> autowire bean properties; it just applies
* explicitly defined property values. Use the {@link #autowireBeanProperties}
* method to autowire an existing bean instance.
* <b>Note: This method requires a bean definition for the given name!</b>
* <p>Does <i>not</i> apply standard {@link BeanPostProcessor BeanPostProcessors}
* callbacks or perform any further initialization of the bean. This interface
* offers distinct, fine-grained operations for those purposes, for example
* {@link #initializeBean}. However, {@link InstantiationAwareBeanPostProcessor}
* callbacks are applied, if applicable to the configuration of the instance.
* @param existingBean the existing bean instance
* @param beanName the name of the bean definition in the bean factory
* (a bean definition of that name has to be available)
* @throws org.springframework.beans.factory.NoSuchBeanDefinitionException
* if there is no bean definition with the given name
* @throws BeansException if applying the property values failed
* @see #autowireBeanProperties
*/
void applyBeanPropertyValues(Object existingBean, String beanName) throws BeansException;
/**
* Initialize the given raw bean, applying factory callbacks
* such as {@code setBeanName} and {@code setBeanFactory},
* also applying all bean post processors (including ones which
* might wrap the given raw bean).
* <p>Note that no bean definition of the given name has to exist
* in the bean factory. The passed-in bean name will simply be used
* for callbacks but not checked against the registered bean definitions.
* @param existingBean the existing bean instance
* @param beanName the name of the bean, to be passed to it if necessary
* (only passed to {@link BeanPostProcessor BeanPostProcessors})
* @return the bean instance to use, either the original or a wrapped one
* @throws BeansException if the initialization failed
*/
Object initializeBean(Object existingBean, String beanName) throws BeansException;
/**
* Apply {@link BeanPostProcessor BeanPostProcessors} to the given existing bean
* instance, invoking their {@code postProcessBeforeInitialization} methods.
* The returned bean instance may be a wrapper around the original.
* @param existingBean the new bean instance
* @param beanName the name of the bean
* @return the bean instance to use, either the original or a wrapped one
* @throws BeansException if any post-processing failed
* @see BeanPostProcessor#postProcessBeforeInitialization
*/
Object applyBeanPostProcessorsBeforeInitialization(Object existingBean, String beanName)
throws BeansException;
/**
* Apply {@link BeanPostProcessor BeanPostProcessors} to the given existing bean
* instance, invoking their {@code postProcessAfterInitialization} methods.
* The returned bean instance may be a wrapper around the original.
* @param existingBean the new bean instance
* @param beanName the name of the bean
* @return the bean instance to use, either the original or a wrapped one
* @throws BeansException if any post-processing failed
* @see BeanPostProcessor#postProcessAfterInitialization
*/
Object applyBeanPostProcessorsAfterInitialization(Object existingBean, String beanName)
throws BeansException;
/**
* Destroy the given bean instance (typically coming from {@link #createBean}),
* applying the {@link org.springframework.beans.factory.DisposableBean} contract as well as
* registered {@link DestructionAwareBeanPostProcessor DestructionAwareBeanPostProcessors}.
* <p>Any exception that arises during destruction should be caught
* and logged instead of propagated to the caller of this method.
* @param existingBean the bean instance to destroy
*/
void destroyBean(Object existingBean);
/**
* Resolve the specified dependency against the beans defined in this factory.
* @param descriptor the descriptor for the dependency
* @param beanName the name of the bean which declares the present dependency
* @param autowiredBeanNames a Set that all names of autowired beans (used for
* resolving the present dependency) are supposed to be added to
* @param typeConverter the TypeConverter to use for populating arrays and
* collections
* @return the resolved object, or {@code null} if none found
* @throws BeansException in dependency resolution failed
*/
Object resolveDependency(DependencyDescriptor descriptor, String beanName,
Set<String> autowiredBeanNames, TypeConverter typeConverter) throws BeansException;
}