springboot-ApplicationListener

• 監聽springboot應用生命週期的事件

新建一個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) {


        // 在這裏能夠監聽到Spring Boot的生命週期
        if (event instanceof ApplicationEnvironmentPreparedEvent) {
            System.out.println("初始化環境變量:ApplicationEnvironmentPreparedEvent");
            // 初始化環境變量
        } 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("應用刷新: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));
            // 應用刷新
        } else if (event instanceof ApplicationReadyEvent) {
            System.out.println("應用已啓動完成:ApplicationReadyEvent");

            // 應用已啓動完成
        } else if (event instanceof ContextStartedEvent) {
            System.out.println("應用啓動，須要在代碼動態添加監聽器纔可捕獲:ContextStartedEvent");
            // 應用啓動，須要在代碼動態添加監聽器纔可捕獲
        } else if (event instanceof ContextStoppedEvent) {
            System.out.println("應用中止:ContextStoppedEvent");
            // 應用中止
        } else if (event instanceof ContextClosedEvent) {
            System.out.println("應用關閉:ContextClosedEvent");
            // 應用關閉
        }
    }



}

在application.properties文件中配置以下：

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

這裏配置了自定義的監聽器的位置。

使用此監聽器能夠在ContextRefreshedEvent事件完成後執行如下準備工做，在ContextStoppedEvent或者ContextCloseEvent事件以前執行收尾工做。