spring源码 AutowireCapableBeanFactory接口

Posted 2020-12-05 李科技

 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引用的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。

/* * Copyright 2002-2016 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
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 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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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;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.beans.factory.NoUniqueBeanDefinitionException;

/**
　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。如果一个类实现了此接口，那么很大程序上它还需要实现BeanFactoryAware接口
　　它可以在应用上下文中返回BeanFactory

 *
 * @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.
　　常量，用于表示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
     * @see #createBean
     * @see #autowire
     * @see #autowireBeanProperties
     */
    int AUTOWIRE_NO = 0;

    /**
     * Constant that indicates autowiring bean properties by name
     * (applying to all bean property setters).
　　　　常量，表示按照名称自动装配bean属性（适用于所有bean属性设置器）
     * @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).
　　　　常量，表示按类型自动装配bean属性（适用于所有bean属性设置器）
     * @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).
　　　　常量，表示按照贪婪策略匹配出最符合的构造方法来自动装配（）
     * @see #createBean
     * @see #autowire
     */
    int AUTOWIRE_CONSTRUCTOR = 3;

    /**
     * Constant that indicates determining an appropriate autowire strategy
     * through introspection of the bean class.
　　　　常量，表示自动识别一种装配策略来自动装配的常量
     * @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 initialization callbacks.
     * It does <i>not</> imply traditional by-name or by-type autowiring of properties;
     * use {@link #createBean(Class, int, boolean)} for those purposes.
     * @param beanClass the class of the bean to create
     * @return the new bean instance
     * @throws BeansException if instantiation or wiring failed
　　　　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
     * and bean property post-processing (e.g. for annotation-driven injection).
通过调用给定bean的after-instantiation及post-processing接口，对bean进行配置。
     * <p>Note: This is essentially intended for (re-)populating annotated fields and
     * methods, 
　　　　此方法主要是用于处理Bean中带有注解的域和方法
　　　　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 those purposes.
　此方法并不意味着by-name或者by-type方式的自动装配，如果需要使用这些功能，可以使用其重载方法autowireBeanProperties
     * @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).
　　　　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。

     * <p>This is effectively a superset of what {@link #initializeBean} provides,
     * fully applying the configuration specified by the corresponding bean definition.
　　　　此方法提供的功能是initializeBean方法的超集，会应用所有注册在bean defineneition中的操作
　　　　不过需要BeanFactory中有参数中指定名字的BeanDefinition.

     * <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;


    //-------------------------------------------------------------------------
    // 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
　　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;

    /**
     * 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
　　　　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 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
　　　　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;

    /**
     * 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
　　　　讲参数中指定的那个bean，注入给定实力当中
　　　　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，
　　　　　autowierBeanProperties方法
　　　　此方法需要BeanFactory中存在指定名字的Bean。除了InstantiationAwareBeanPostProcessor的回调函数外
　　　　此方法不会再bean上应用其它的例如BeanPostProcessors
　　　　等回调方法。不过可以调用其它诸如initializeBean等方法来达到目的

     */
    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
　　　　初始化参数中指定的bean,调用任何其注册的回调函数如setBean,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;

    /**
     * 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
　　　　调用参数中指定bean的postProcessBeforeInitialization方法
     */
    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
　　　　调用参数中指定bean的postProcessAfterInitialization方法
     */
    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
　　　　　销毁参数中给定的bean，同时调用此bean上的DisposableBean和DestructionAwareBeanPostProce
　　　　　在销毁途中，任何的异常情况都只应该被捕获和记录，而不应该向外抛出。

     */
    void destroyBean(Object existingBean);


    //-------------------------------------------------------------------------
    // Delegate methods for resolving injection points
    //-------------------------------------------------------------------------

    /**
     * Resolve the bean instance that uniquely matches the given object type, if any,
     * including its bean name.
     * <p>This is effectively a variant of {@link #getBean(Class)} which preserves the
     * bean name of the matching instance.
     * @param requiredType type the bean must match; can be an interface or superclass.
     * {@code null} is disallowed.
     * @return the bean name plus bean instance
     * @throws NoSuchBeanDefinitionException if no matching bean was found
     * @throws NoUniqueBeanDefinitionException if more than one matching bean was found
     * @throws BeansException if the bean could not be created
     * @since 4.3.3
     * @see #getBean(Class)
　　　　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;

    /**
     * Resolve the specified dependency against the beans defined in this factory.
     * @param descriptor the descriptor for the dependency (field/method/constructor)
     * @param requestingBeanName the name of the bean which declares the given dependency
     * @return the resolved object, or {@code null} if none found
     * @throws NoSuchBeanDefinitionException if no matching bean was found
     * @throws NoUniqueBeanDefinitionException if more than one matching bean was found
     * @throws BeansException if dependency resolution failed for any other reason
     * @since 2.5
     * @see #resolveDependency(DependencyDescriptor, String, Set, TypeConverter)
　　　　解析出在Factory中与指定bean有指定依赖关系的bean
     */
    Object resolveDependency(DependencyDescriptor descriptor, String requestingBeanName) throws BeansException;

    /**
     * Resolve the specified dependency against the beans defined in this factory.
　　　　解析指定bean在Factory中的依赖关系
     * @param descriptor the descriptor for the dependency (field/method/constructor)
　　　　　　　　　　　　　　　　依赖描述（field/method/constructor）
     * @param requestingBeanName the name of the bean which declares the given dependency
　　　　　　　　　　　　　　　　　　　　依赖描述所属的Bean
     * @param autowiredBeanNames a Set that all names of autowired beans (used for
     * resolving the given dependency) are supposed to be added to
　　　　　　　　　autowireBeanNames 与指定bean有依赖关系的Bean
     * @param typeConverter the TypeConverter to use for populating arrays and collections
　　　　　　　　　　　　　　　　　　用以转换数组和连表的转换器
     * @return the resolved object, or {@code null} if none found
　　　　　　　　　　解析结果，可能为null
     * @throws NoSuchBeanDefinitionException if no matching bean was found
     * @throws NoUniqueBeanDefinitionException if more than one matching bean was found
     * @throws BeansException if dependency resolution failed for any other reason
     * @since 2.5
     * @see DependencyDescriptor

　　　　

     */
    Object resolveDependency(DependencyDescriptor descriptor, String requestingBeanName,
            Set<String> autowiredBeanNames, TypeConverter typeConverter) throws BeansException;

}

 

学习参考原创的网址：https://blog.csdn.net/weixin_39165515/article/details/77096774