[오류 기록]Could not resolve org.springframework.boot:spring-boot-gradle-plugin:3.0.1.

오류 로그

A problem occurred configuring root project 'helloJava'.
> Could not resolve all files for configuration ':classpath'.
   > Could not resolve org.springframework.boot:spring-boot-gradle-plugin:3.0.1.
     Required by:
         project : > org.springframework.boot:org.springframework.boot.gradle.plugin:3.0.1
      > No matching variant of org.springframework.boot:spring-boot-gradle-plugin:3.0.1 was found. The consumer was configured to find a runtime of a library compatible with Java 11, packaged as a jar, and its dependencies declared externally, as well as attribute 'org.gradle.plugin.api-version' with value '7.6' but:
          - Variant 'apiElements' capability org.springframework.boot:spring-boot-gradle-plugin:3.0.1 declares a library, packaged as a jar, and its dependencies declared externally:
              - Incompatible because this component declares an API of a component compatible with Java 17 and the consumer needed a runtime of a component compatible with Java 11
              - Other compatible attribute:
                  - Doesn't say anything about org.gradle.plugin.api-version (required '7.6')
          - Variant 'javadocElements' capability org.springframework.boot:spring-boot-gradle-plugin:3.0.1 declares a runtime of a component, and its dependencies declared externally:
              - Incompatible because this component declares documentation and the consumer needed a library
              - Other compatible attributes:
                  - Doesn't say anything about its target Java version (required compatibility with Java 11)
                  - Doesn't say anything about its elements (required them packaged as a jar)
                  - Doesn't say anything about org.gradle.plugin.api-version (required '7.6')
          - Variant 'mavenOptionalApiElements' capability org.springframework.boot:spring-boot-gradle-plugin-maven-optional:3.0.1 declares a library, packaged as a jar, and its dependencies declared externally:
              - Incompatible because this component declares an API of a component compatible with Java 17 and the consumer needed a runtime of a component compatible with Java 11
              - Other compatible attribute:
                  - Doesn't say anything about org.gradle.plugin.api-version (required '7.6')
          - Variant 'mavenOptionalRuntimeElements' capability org.springframework.boot:spring-boot-gradle-plugin-maven-optional:3.0.1 declares a runtime of a library, packaged as a jar, and its dependencies declared externally:
              - Incompatible because this component declares a component compatible with Java 17 and the consumer needed a component compatible with Java 11
              - Other compatible attribute:
                  - Doesn't say anything about org.gradle.plugin.api-version (required '7.6')
          - Variant 'runtimeElements' capability org.springframework.boot:spring-boot-gradle-plugin:3.0.1 declares a runtime of a library, packaged as a jar, and its dependencies declared externally:
              - Incompatible because this component declares a component compatible with Java 17 and the consumer needed a component compatible with Java 11
              - Other compatible attribute:
                  - Doesn't say anything about org.gradle.plugin.api-version (required '7.6')
          - Variant 'sourcesElements' capability org.springframework.boot:spring-boot-gradle-plugin:3.0.1 declares a runtime of a component, and its dependencies declared externally:
              - Incompatible because this component declares documentation and the consumer needed a library
              - Other compatible attributes:
                  - Doesn't say anything about its target Java version (required compatibility with Java 11)
                  - Doesn't say anything about its elements (required them packaged as a jar)
                  - Doesn't say anything about org.gradle.plugin.api-version (required '7.6')

원인

• 현재 spring 프로젝트를 생성하면 boot는 3.0.1이 생성이 기본으로 설정되어 있다.
• 그러나, 이는 Java 17에서 지원을 하는 것이고 Java 11에서는 지원을 하지 않는다.

Fix

• Java 17 를 사용하고 싶다면 boot 3.x번대로 설정을 해도 괜찮다. 2.x도 괜찮다.

plugins {
    id 'java'
    id 'org.springframework.boot' version '3.0.1'
    id 'io.spring.dependency-management' version '1.1.0'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '17'

repositories {
    mavenCentral()
}

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

tasks.named('test') {
    useJUnitPlatform()
}

• Java11을 사용하고 싶다면 boot 2.x 로 설정을 하자. 3.x는 빌드 실패가 난다.

plugins {
    id 'java'
    id 'org.springframework.boot' version '2.7.7'
    id 'io.spring.dependency-management' version '1.1.0'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '11'

repositories {
    mavenCentral()
}

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

tasks.named('test') {
    useJUnitPlatform()
}