项目场景：

spring-boot-version: 2.4.2
spring-cloud-version: 2020.0.1
spring-cloud-alibaba-version: 2021.1

问题描述

在配置过devtools热更新之后，更新报错为

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'requestMappingHandlerAdapter' defined in class path resource [org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfiguration$EnableWebMvcConfiguration.class]: Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'springApplicationAdminRegistrar' defined in class path resource [org/springframework/boot/autoconfigure/admin/SpringApplicationAdminJmxAutoConfiguration.class]: Invocation of init method failed; nested exception is javax.management.InstanceAlreadyExistsException: org.springframework.boot:type=Admin,name=SpringApplication
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:617) ~[spring-beans-5.3.3.jar:5.3.3]
	...

主要错误为nested exception is javax.management.InstanceAlreadyExistsException: org.springframework.boot:type=Admin,name=SpringApplication

直接粘贴错误，经过各种google搜索，并没有找到相关解决方案

原因分析：

再次分析更新过程，发现spring的banner输出了2次

29秒一次

36秒又一次

再次google搜索devtools restarts twice

找到相关解决方法：
DevTools restarts twice in Intellij

解决方案：

参考添加配置

spring:
  devtools:
    restart:
      quiet-period: 900

问题解决