SpringBoot

从Spring Boot 2.1开始必须启用Bean覆盖，

https://github.com/spring-projects/spring-boot/wiki/Spring-Boot-2.1-Release-Notes

Bean Overriding
Bean overriding has been disabled by default to prevent a bean being accidentally overridden. If you are relying on overriding, you will need to set spring.main.allow-bean-definition-overriding to true.

Set

spring.main.allow-bean-definition-overriding=true

or yml,

spring:   main:     allow-bean-definition-overriding: true

再次启用覆盖。

Bean覆盖基于Bean的名称而不是其类型。例如

@Beanpublic ClassA class(){   return new ClassA();}@Beanpublic ClassB class(){   return new ClassB();}

在> 2.1中将导致此错误，默认情况下，Bean名称取自方法名称。重命名方法或将name属性添加到Bean注释将是有效的解决方案。