ApplicationEventPublisher筆記

ApplicationEventPublisher是ApplicationContext的父接口之一。這接口的作用是：Interface that encapsulates event publication functionality.

功能就是發布事件，也就是把某個事件告訴的所有與這個事件相關的監聽器。

這個接口只有兩個方法（這兩個是重載方法）。所以把整個接口的代碼都貼上來。

/**
 * Interface that encapsulates event publication functionality.
 * Serves as super-interface for {@link ApplicationContext}.
 *
 * @author Juergen Hoeller
 * @author Stephane Nicoll
 * @since 1.1.1
 * @see ApplicationContext
 * @see ApplicationEventPublisherAware
 * @see org.springframework.context.ApplicationEvent
 * @see org.springframework.context.event.EventPublicationInterceptor
 */
public interface ApplicationEventPublisher {

    /**
     * Notify all <strong>matching</strong> listeners registered with this
     * application of an application event. Events may be framework events
     * (such as RequestHandledEvent) or application-specific events.
     * @param event the event to publish
     * @see org.springframework.web.context.support.RequestHandledEvent
 
     */
    void publishEvent(ApplicationEvent event);

    /**
     * Notify all <strong>matching</strong> listeners registered with this
     * application of an event.
     * <p>If the specified {@code event} is not an {@link ApplicationEvent},
     * it is wrapped in a {@link PayloadApplicationEvent}.
     * @param event the event to publish
     * @since 4.2
     * @see PayloadApplicationEvent
     */
    void publishEvent(Object event);

}

這個方法會通知的所有與事件相匹配的監聽器。這些監聽可能是spring框架的監聽器，也有可能是特定的監聽器。