Spring系列之-Aware系列接口

 Aware是一个空接口，其目的是标明一些列接口，这些接口主要用于获取一些上下文的实现。从Spring文档中可以看到，目前一Aware结尾的接口主要有下列接口:[ApplicationContextAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/context/ApplicationContextAware.html), [ApplicationEventPublisherAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/context/ApplicationEventPublisherAware.html), [BeanClassLoaderAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/beans/factory/BeanClassLoaderAware.html), [BeanFactoryAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/beans/factory/BeanFactoryAware.html), [BeanNameAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/beans/factory/BeanNameAware.html), [BootstrapContextAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/jca/context/BootstrapContextAware.html), [EmbeddedValueResolverAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/context/EmbeddedValueResolverAware.html), [EnvironmentAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/context/EnvironmentAware.html), [ImportAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/context/annotation/ImportAware.html), [LoadTimeWeaverAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/context/weaving/LoadTimeWeaverAware.html), [MessageSourceAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/context/MessageSourceAware.html), [NotificationPublisherAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/jmx/export/notification/NotificationPublisherAware.html), [ResourceLoaderAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/context/ResourceLoaderAware.html), [SchedulerContextAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/scheduling/quartz/SchedulerContextAware.html), [ServletConfigAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/web/context/ServletConfigAware.html), [ServletContextAware](https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/web/context/ServletContextAware.html)。

 下面将对这些接口具体功能及其实现原理做简要分析：

功能介绍:

1.ApplicationContextAware

实现ApplicationContextAware接口的Bean可以获得Spring上下文信息ApplicationContext，ApplicationContextAware接口内部只有一个方法：

void setApplicationContext(ApplicationContext applicationContext) throws BeansException;

该方法会在Spring容器加载完后被调用，用户只要实现这个接口就能拿到Spring上下文信息。

2.ApplicationEventPublisherAware

该接口主要用于发布一些事件时使用，接口方法如下:

void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher);

实现该接口能获取到ApplicationEventPublisher，这个接口具备发布事件功能。

3.BeanClassLoaderAware

该接口可以获取到加载当前类的类加载器，

void setBeanClassLoader(ClassLoader classLoader);