spring的aware是怎么被回调的

spring-ioc流程

  1:将bean放到一个容器中

  2:spring中的aware的子类规定好回调接口

public interface ApplicationContextAware extends Aware {

    void setApplicationContext(ApplicationContext applicationContext) throws BeansException;

}

  3:写一个接口,实现 ApplicationContextAware

@Component
@Configuration
public class WebApplicationContextAware implements ApplicationContextAware {

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        System.out.println("---- ApplicationContextAware ----");
    }
}

        4:遍历容器中的每个bean与Aware比较

    private void invokeAwareInterfaces(Object bean) {
        if (bean instanceof Aware) {
            if (bean instanceof EnvironmentAware) {
                ((EnvironmentAware) bean).setEnvironment(this.applicationContext.getEnvironment());
            }
            if (bean instanceof EmbeddedValueResolverAware) {
                ((EmbeddedValueResolverAware) bean).setEmbeddedValueResolver(this.embeddedValueResolver);
            }
            if (bean instanceof ResourceLoaderAware) {
                ((ResourceLoaderAware) bean).setResourceLoader(this.applicationContext);
            }
            if (bean instanceof ApplicationEventPublisherAware) {
                ((ApplicationEventPublisherAware) bean).setApplicationEventPublisher(this.applicationContext);
            }
            if (bean instanceof MessageSourceAware) {
                ((MessageSourceAware) bean).setMessageSource(this.applicationContext);
            }
            if (bean instanceof ApplicationContextAware) {
                ((ApplicationContextAware) bean).setApplicationContext(this.applicationContext);
            }
        }
    }

  当bean是  Aware 的实现类,则进行下一步处理。直到使用 bean 调用 对应的方法

 

WebApplicationContextAware 注入到ioc容器后,遍历容器中的bean的时候,判断该bean是否为Aware类型的,如果是,会用ioc容貌后期中的 webApplicationContextAware 调用 setApplicationContext 方法。。实现其他类型的Aware回调方式类似
原文地址:https://www.cnblogs.com/draymond/p/12911163.html