pom文件添加依赖包

<dependency>  
        <groupId>org.springframework.boot</groupId>  
        <artifactId>spring-boot-devtools</artifactId>  
        <optional>true</optional>  
 </dependency>
 
 
 <build>
       <plugins>
           <plugin>
               <groupId>org.springframework.boot</groupId>
               <artifactId>spring-boot-maven-plugin</artifactId>
               <configuration>
                   <fork>true</fork><!--必须添加这个配置-->
               </configuration>
           </plugin>
       </plugins>
   </build>

settings配置搜索compiler并选中确认

window快捷键 Shift+Ctrl+Alt+/选择Registry

选中以后close  重启idea即可生效