Spring Event handling Example

In Spring Event handling in the ApplicationContext is provided through the ApplicationEvent class and ApplicationListener interface
In general spring has the following events

• ContextRefreshedEvent
• ContextStartedEvent
• ContextStoppedEvent
• ContextClosedEvent
• RequestHandledEvent 

ApplicationEvent is the super class, all the above classes are extending this class, here is one example to log the spring events

Create a class which implements ApplicationListener

package com.vinod.test;

import org.springframework.context.ApplicationEvent;
import org.springframework.context.ApplicationListener;
import org.springframework.stereotype.Component;
@Component
public class MyEventListener implements ApplicationListener<ApplicationEvent> {    
    public void onApplicationEvent(ApplicationEvent applicationEvent) {
        System.out.println("Current Event is "+ applicationEvent.getClass().getName() + " received!");     
    }

}
 

Create a Simple bean 

package com.vinod.test;
import org.springframework.stereotype.Component;

@Component
public class Customer {
    public String getCustomer() {
        return "Thomas....Regular customer";
    }
}
 

Spring Configuration

package com.vinod.test;

import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
@Configuration
@ComponentScan("com.vinod.test")
public class MySpringConifg {
   
}
 

Create a Test class

package com.vinod.test;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class EventTest {

    public static void main(String[] args) {

        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
        context.register(MySpringConifg.class);
        context.refresh();
        Customer cd = context.getBean(Customer.class);
        System.out.println(cd.getCustomer());

    }

}
 

Output

Current Event is org.springframework.context.event.ContextRefreshedEvent received!

Thomas....Regular customer

Download this example

https://github.com/kkvinodkumaran/spring