[flutter] mobile_scanner 사용시 :app:checkDebugDuplicateClasses 오류 문제

QR Code를 스캔하기 위해 mobile_scanner을 설치했다. flutter create하고 이 패키지만 설치했는데 다음과 같은 오류 메세지가 나왔다.

오류 코드

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:checkDebugDuplicateClasses'.
> A failure occurred while executing com.android.build.gradle.internal.tasks.CheckDuplicatesRunnable
   > Duplicate class kotlin.collections.jdk8.CollectionsJDK8Kt found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.internal.jdk7.JDK7PlatformImplementations found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.internal.jdk7.JDK7PlatformImplementations$ReflectSdkVersion found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.internal.jdk8.JDK8PlatformImplementations found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.internal.jdk8.JDK8PlatformImplementations$ReflectSdkVersion found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.io.path.DirectoryEntriesReader found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.ExperimentalPathApi found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.FileVisitorBuilder found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.FileVisitorBuilderImpl found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.FileVisitorImpl found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.LinkFollowing found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.PathNode found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.PathRelativizer found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.PathTreeWalk found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.PathTreeWalk$bfsIterator$1 found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.PathTreeWalk$dfsIterator$1 found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.PathTreeWalkKt found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.PathWalkOption found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.PathsKt found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.PathsKt__PathReadWriteKt found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.io.path.PathsKt__PathUtilsKt found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.jdk7.AutoCloseableKt found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk7-1.7.22 (org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.22)
     Duplicate class kotlin.jvm.jdk8.JvmRepeatableKt found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.jvm.optionals.OptionalsKt found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.random.jdk8.PlatformThreadLocalRandom found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.streams.jdk8.StreamsKt found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.streams.jdk8.StreamsKt$asSequence$$inlined$Sequence$1 found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.streams.jdk8.StreamsKt$asSequence$$inlined$Sequence$2 found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.streams.jdk8.StreamsKt$asSequence$$inlined$Sequence$3 found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.streams.jdk8.StreamsKt$asSequence$$inlined$Sequence$4 found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.text.jdk8.RegexExtensionsJDK8Kt found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)
     Duplicate class kotlin.time.jdk8.DurationConversionsJDK8Kt found in modules jetified-kotlin-stdlib-1.8.22 (org.jetbrains.kotlin:kotlin-stdlib:1.8.22) and jetified-kotlin-stdlib-jdk8-1.7.10 (org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10)

     Go to the documentation to learn how to <a href="d.android.com/r/tools/classpath-sync-errors">Fix dependency resolution errors</a>.

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 6s
Error: Gradle task assembleDebug failed with exit code 1

원인

읽어보니 Kotlin 버전 관련해서 발생한 문제였다.

• Github: Error when building app:checkDebugDuplicateClasses

해결

Kotlin 버전을 1.8.22로 올린다.
이때 Flutter 버전에 따라 해결하는 방법이 조금 다르다.(<3.16방식으로 해도 되긴 하는데, Flutter 문서에서 deprecated되었다고 한다.)

<3.16: {project_name}/android/app/build.gradle에 코드 추가

configurations.all {
    resolutionStrategy {
        force 'org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.8.22'
    }
}

>=3.16: {project_name}\android\settings.gradle의 org.jetbrains.kotlin.android 버전을 1.8.22로 수정

plugins {
    id "dev.flutter.flutter-plugin-loader" version "1.0.0"
    id "com.android.application" version "7.3.0" apply false
//    id "org.jetbrains.kotlin.android" version "1.7.10" apply false // before
    id "org.jetbrains.kotlin.android" version "1.8.22" apply false // after
}

해결!

참고 링크

• Github: Error when building app:checkDebugDuplicateClasses #957
• Stack Overflow: Flutter version 3.19.2 requires a newer version of the Kotlin Gradle plugin. /android/build.gradle: ext.kotlin_version = '<latest-version>'
• Flutter Docs - https://docs.flutter.dev/release/breaking-changes/flutter-gradle-plugin-apply