Gradle

plugins {
    id 'org.springframework.boot' version '2.6.1'
    id 'io.spring.dependency-management' version '1.0.11.RELEASE'
    id 'java'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '1.8'

repositories {
    mavenCentral()
}

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter'
    implementation 'org.springframework.boot:spring-boot-starter-web'
    developmentOnly 'org.springframework.boot:spring-boot-devtools'
    testImplementation 'org.springframework.boot:spring-boot-starter-test'
}

test {
    useJUnitPlatform()
}

(1) plugins
(2) repositories : dependencies에서 선언한 의존체와 필수 라이브러리를 가져오기 위해 접속할 서버 정보를 적는다.
(3) dependencies
(4) test