Spring(十)之自定义事件

编写自定义事件的简单流程如下:

(1)编写CustomEvent.java

package com.tutorialspoint;

import org.springframework.context.ApplicationEvent;

public class CustomEvent extends ApplicationEvent{
   public CustomEvent(Object source) {
      super(source);
   }
   public String toString(){
      return "My Custom Event";
   }
}

(2)编写CustomEventPublisher.java

package com.tutorialspoint;

import org.springframework.context.ApplicationEventPublisher;
import org.springframework.context.ApplicationEventPublisherAware;

public class CustomEventPublisher implements ApplicationEventPublisherAware {
   private ApplicationEventPublisher publisher;
   
   public void setApplicationEventPublisher (ApplicationEventPublisher publisher) {
      this.publisher = publisher;
   }
   public void publish() {
      CustomEvent ce = new CustomEvent(this);
      publisher.publishEvent(ce);
   }
}

(3)编写CustomEventHandler.java

package com.tutorialspoint;

import org.springframework.context.ApplicationListener;

public class CustomEventHandler implements ApplicationListener<CustomEvent> {
   public void onApplicationEvent(CustomEvent event) {
      System.out.println(event.toString());
   }
}

(4)编写MainApp.java

package com.tutorialspoint;

import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class MainApp {
   public static void main(String[] args) {
      ConfigurableApplicationContext context = 
         new ClassPathXmlApplicationContext("Beans.xml");
      
      CustomEventPublisher cvp = 
         (CustomEventPublisher) context.getBean("customEventPublisher");
      
      cvp.publish();  
      cvp.publish();
   }
}

(5)编写Beans.xml

<?xml version = "1.0" encoding = "UTF-8"?>

<beans xmlns = "http://www.springframework.org/schema/beans"
   xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation = "http://www.springframework.org/schema/beans
   http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

   <bean id = "customEventHandler" class = "com.tutorialspoint.CustomEventHandler"/>
   <bean id = "customEventPublisher" class = "com.tutorialspoint.CustomEventPublisher"/>

</beans>

(6)运行MainApp.java中的main方法