1. dependency 추가
Maven
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
Gradle
dependencies {
developmentOnly 'org.springframework.boot:spring-boot-devtools'
}
2. application.properties 추가
spring.devtools.livereload.enabled=true
spring.thymeleaf.cache=false
3. Intellij 환경설정 수정
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Build project automatically 체크
4. Intellij Registry 수정
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compiler.automake.allow.when.app.running 체크