• 监听springboot应用生命周期的事件

新建一个ApplicationContextListener.java

package com.wangxh.email.listener;

import org.apache.commons.lang3.builder.ToStringBuilder;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanInitializationException;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.mail.MailProperties;
import org.springframework.boot.autoconfigure.web.ServerProperties;
import org.springframework.boot.context.event.ApplicationEnvironmentPreparedEvent;
import org.springframework.boot.context.event.ApplicationPreparedEvent;
import org.springframework.boot.context.event.ApplicationReadyEvent;
import org.springframework.context.*;
import org.springframework.context.event.*;
import org.springframework.core.style.ToStringCreator;
import org.springframework.stereotype.Component;
import org.springframework.util.ObjectUtils;
import org.springframework.util.StringUtils;


public class ApplicationContextListener implements  ApplicationListener {

    ApplicationContext applicationContext;

    MailProperties mailProperties;

    ServerProperties serverProperties;
  
    @Override
    public void onApplicationEvent(ApplicationEvent event) {


        // 在这里可以监听到Spring Boot的生命周期
        if (event instanceof ApplicationEnvironmentPreparedEvent) {
            System.out.println("初始化环境变量:ApplicationEnvironmentPreparedEvent");
            // 初始化环境变量
        } else if (event instanceof ApplicationPreparedEvent) {
            System.out.println("初始化完成:ApplicationPreparedEvent");

            // 初始化完成
        } else if (event instanceof ContextRefreshedEvent) {
            System.out.println("应用刷新:ContextRefreshedEvent");
            applicationContext= ((ContextRefreshedEvent) event).getApplicationContext();
            mailProperties=applicationContext.getBean(MailProperties.class);
            serverProperties=applicationContext.getBean(ServerProperties.class);
            System.out.println("serverProperties:"+ToStringBuilder.reflectionToString(serverProperties));
            System.out.println("mailProperties:"+ ToStringBuilder.reflectionToString(mailProperties));
            // 应用刷新
        } else if (event instanceof ApplicationReadyEvent) {
            System.out.println("应用已启动完成:ApplicationReadyEvent");

            // 应用已启动完成
        } else if (event instanceof ContextStartedEvent) {
            System.out.println("应用启动，需要在代码动态添加监听器才可捕获:ContextStartedEvent");
            // 应用启动，需要在代码动态添加监听器才可捕获
        } else if (event instanceof ContextStoppedEvent) {
            System.out.println("应用停止:ContextStoppedEvent");
            // 应用停止
        } else if (event instanceof ContextClosedEvent) {
            System.out.println("应用关闭:ContextClosedEvent");
            // 应用关闭
        }
    }



}

在application.properties文件中配置如下：

context.listener.classes=com.wangxh.email.listener.ApplicationContextListener

这里配置了自定义的监听器的位置。

使用此监听器可以在ContextRefreshedEvent事件完成后执行以下准备工作，在ContextStoppedEvent或者ContextCloseEvent事件之前执行收尾工作。