How to Resolve Duplicate Class Errors in Kotlin Android Projects

How to Resolve Duplicate Class Errors in Kotlin Android Projects

6 June 2024 Stephan Petzl Leave a comment Tech-Help

Encountering duplicate class errors in your Kotlin Android project can be frustrating. These errors often occur due to conflicting dependencies within your project. Below, we provide a step-by-step guide to help you resolve these issues effectively.

Understanding the Issue

Duplicate class errors typically arise when multiple versions of the same library are included in your project. This can happen when you have dependencies that transitively include different versions of the same library. In this specific case, the error involves duplicate classes in the Kotlin standard library.

Step-by-Step Solution

Follow these steps to resolve the duplicate class errors in your Kotlin Android project:

Step 1: Update Kotlin Plugin Version

First, ensure that you are using the latest Kotlin plugin version. Update your build.gradle file as follows:

plugins {
    id '' version '1.8.0' apply false

Synchronize your project and invalidate caches if necessary.

Step 2: Override Dependency Versions

Next, override the versions of the conflicting dependencies in your app/build.gradle file:

dependencies {
    constraints {
        implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.8.0") {
            because("kotlin-stdlib-jdk7 is now a part of kotlin-stdlib")
        implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.8.0") {
            because("kotlin-stdlib-jdk8 is now a part of kotlin-stdlib")

This ensures that the correct versions of the Kotlin standard library are used, preventing conflicts.

Step 3: Remove Redundant Dependencies

If you have explicit dependencies on older versions of the Kotlin standard library, remove them. For example, remove lines like:

implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"

Step 4: Synchronize and Rebuild

Finally, synchronize your project with Gradle and rebuild it. This should resolve the duplicate class errors.

Additional Resources

For more information on managing dependencies in your Kotlin project, you can refer to our documentation on virtual test devices and running test batches.

Streamlining Testing with Repeato

Manual management of dependencies and resolving conflicts can be time-consuming. To streamline your testing process, consider using Repeato, a no-code test automation tool for iOS and Android. Repeato allows you to create, run, and maintain automated tests for your apps quickly and efficiently. By leveraging computer vision and AI, Repeato ensures that your focus remains on developing a great product while automating the testing process.

Learn more about how Repeato can enhance your development workflow by visiting our getting started guide.

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