添加pom依赖

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-devtools</artifactId>
    <optional>true</optional>
    <scope>runtime</scope>
</dependency>

maven plugin中添加

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
            <configuration>
            	<fork>true</fork>
            </configuration>
            <dependencies>
                <!-- spring热部署-->
                <dependency>
                    <groupId>org.springframework</groupId>
                    <artifactId>springloaded</artifactId>
                    <version>1.2.6.RELEASE</version>
                    <scope>provided</scope>
                </dependency>
            </dependencies>
        </plugin>
    </plugins>
</build>

application.yml中添加

spring:
  devtools:
    restart:
      #热部署生效
      enabled: true

当我们修改了java类后，IDEA默认是不自动编译的，而spring-boot-devtools又是监测classpath下的文件发生变化才会重启应用

• Ctrl+F9重新编译一下即可
• 1. File>>Settings>>Build>>Compiler>>Build Project automatically
  2. ctrl + shift + alt + /,选择Registry,勾上 Compiler autoMake allow when app running