jar包冲突了，具体冲突是log4j-slf4j-impl-2.10.0.jar和log4j-to-slf4j-2.10.0.jar，把log4j-slf4j-impl-2.10.0.jar在pom文件里排除引用即可，使用exclusions，解决方法如下：

    1. <dependency>
    2.     <groupId>org.springframework.boot</groupId>
    3.     <artifactId>spring-boot-starter-web</artifactId>
    4.     <exclusions>
    5.         <exclusion>
    6.             <groupId>org.springframework.boot</groupId>
    7.             <artifactId>spring-boot-starter-logging</artifactId>
    8.         </exclusion>
    9.     </exclusions>
    10. </dependency>
    11. <dependency>
    12.     <groupId>org.springframework.boot</groupId>
    13.     <artifactId>spring-boot-starter-log4j2</artifactId>
    14. </dependency>