How to Fix “Gradle task assembleDebug failed with exit code 1”

Encountering the “Gradle task assembleDebug failed with exit code 1” error can be a frustrating experience for Android developers. This error indicates a problem during the build process when Gradle is trying to assemble the debug version of your Android application. Exit code 1 generally signifies that the build process failed due to some error. This comprehensive guide explores the common causes behind this error and provides detailed solutions to resolve it.

Understanding the Error

The “Gradle task assembleDebug failed with exit code 1” error doesn’t pinpoint the exact problem. You need to examine the error output carefully to understand the root cause. Usually, the error message is accompanied by other error logs that provide more specific information. Let’s dive into the common reasons behind this error and how to address them.

Common Causes and Solutions

Here are the most common causes and their corresponding solutions:

1. Compilation Errors

• Cause: The most frequent cause is a compilation error in your Java or Kotlin code, XML layouts, or other resources. This can include syntax errors, type mismatches, missing imports, or incorrect resource references.
• Solution:
  • Examine the Error Log: Carefully read the Gradle console output. Look for specific error messages related to your code files. The error log usually provides the file name and line number where the error occurred.
  • Fix Syntax Errors: Correct any syntax errors like missing semicolons, incorrect variable declarations, or wrong operator usage.
  • Resolve Type Mismatches: Ensure that you are using the correct data types in your code. For example, assigning a string value to an integer variable will cause a type mismatch error.
  • Check Imports: Make sure all necessary classes and libraries are imported correctly. If a class is not imported, the compiler won’t be able to find it.
  • Verify Resource References: Double-check that all resource references in your code and XML layouts are correct. For example, make sure that the ID of a view in your XML layout matches the ID you are using in your Java/Kotlin code.
  • Clean and Rebuild: After fixing the errors, clean the project (Build -> Clean Project) and then rebuild it (Build -> Rebuild Project).

2. Dependency Conflicts

• Cause: Dependency conflicts occur when different libraries or modules in your project require different versions of the same dependency. This can lead to unexpected behavior and build failures.

• Solution:

  • Gradle Dependency Report: Use the Gradle dependency report to identify conflicting dependencies. Open the Gradle tool window in Android Studio, navigate to your_module -> Tasks -> android -> dependencies, and run the dependencies task. This will generate a report showing all dependencies and their versions.
  • Exclude Conflicting Dependencies: In your build.gradle file, use the exclude keyword to exclude the conflicting dependency from one of the modules. For example:

  dependencies {
      implementation('com.example.library:1.0') {
          exclude group: 'com.google.guava', module: 'guava'
      }
      implementation 'com.google.guava:guava:27.0'
  }
  

  • Force Dependency Versions: Use the force keyword in your build.gradle file to force a specific version of a dependency. Be cautious when forcing versions, as it can lead to runtime issues if the forced version is not compatible with other parts of your project.

  configurations.all {
      resolutionStrategy {
          force 'com.google.guava:guava:27.0'
      }
  }
  

3. Resource Merging Errors

• Cause: Resource merging errors happen when there are conflicts in your resource files (e.g., duplicate resources with the same name in different modules).
• Solution:
  • Examine the Error Log: The error log usually indicates which resource files are causing the conflict.
  • Remove Duplicate Resources: Remove any duplicate resource files or rename them to avoid conflicts.
  • Use Resource Overrides: Use resource overrides to provide different resource values for different build types or product flavors. This can be useful when you need to customize resources for different environments (e.g., debug vs. release).

4. Gradle Version Incompatibility

• Cause: Using an outdated or incompatible version of Gradle can cause build errors.
• Solution:
  • Update Gradle Version: Update your Gradle version to the latest stable version or a version that is compatible with your Android Studio version. You can update the Gradle version in your gradle-wrapper.properties file.
  • Update Gradle Plugin: Ensure that you are using a compatible version of the Android Gradle plugin in your build.gradle file.

5. Insufficient Memory

• Cause: The Gradle build process can be memory-intensive. If your system doesn’t have enough memory, it can lead to build failures.

• Solution:

  • Increase Gradle Memory: Increase the Gradle memory allocation by adding the following line to your gradle.properties file:

  org.gradle.jvmargs=-Xmx4096m
  

  This will allocate 4GB of memory to the Gradle process. Adjust the value as needed.

6. Corrupted Gradle Cache

• Cause: A corrupted Gradle cache can cause build failures.

• Solution:

  • Clean Gradle Cache: Clean the Gradle cache by running the following command in your terminal:

  ./gradlew cleanBuildCache
  

  Or you can manually delete the contents of the Gradle cache directory (usually located in ~/.gradle/caches).

7. NDK Issues

• Cause: If you’re using the Native Development Kit (NDK), problems with your native code or NDK configuration can lead to build failures.
• Solution:
  • Check NDK Configuration: Verify that your NDK configuration in your build.gradle file is correct.
  • Examine Native Code: Check your C/C++ code for errors. Use a debugger to identify and fix any issues.

Troubleshooting Steps

1. Clean Project: Build -> Clean Project
2. Rebuild Project: Build -> Rebuild Project
3. Invalidate Caches / Restart: File -> Invalidate Caches / Restart -> Invalidate and Restart
4. Update Android Studio and Gradle: Make sure you are using the latest versions of Android Studio and Gradle.
5. Check System Resources: Ensure that your system has enough memory and disk space.

Conclusion

The “Gradle task assembleDebug failed with exit code 1” error can be caused by various issues. By systematically examining the error log, identifying the root cause, and applying the appropriate solution, you can resolve this error and get your Android project building successfully. Remember to always keep your Android Studio and Gradle versions up-to-date and to carefully manage your project’s dependencies.