一、配置idea
a、Ctrl+Alt+S => Compiler => Build project automatically；
b、Ctrl+Alt+Shift+/ => Registry... => compiler.automake.allow.when.app.running；
二、配置pom
<!-- 加入以下依赖,代码作了修改,不用重新运行 -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>springloaded</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
</dependency>
原文：https://www.cnblogs.com/linding/p/12591033.html