错误：com.android.dex.DexException：多个dex文件定义了Ledu / umd / cs / findbugs / annotations / NonNull；

Question

My module dependencies:

configurations.all {
    resolutionStrategy {
        force 'junit:junit:4.12'
    }
}

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    androidTestCompile('com.android.support.test.espresso:espresso-
core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-
annotations'
})

compile 'com.android.support:appcompat-v7:25.3.1'
compile 'com.android.support.constraint:constraint-layout:1.0.2'
testCompile 'junit:junit:4.12'

provided 'org.projectlombok:lombok:1.16.16'
annotationProcessor "org.projectlombok:lombok:1.16.16"

// For DL4J
compile 'org.deeplearning4j:deeplearning4j-core:0.9.1'
compile 'org.deeplearning4j:deeplearning4j-zoo:0.9.1'
compile 'org.nd4j:nd4j-native:0.9.1'
compile 'org.nd4j:nd4j-native:0.9.1:android-arm'
compile 'org.bytedeco.javacpp-presets:openblas:0.2.19-1.3:android-arm'
compile project(':dlbenchmark')
}

dlbenchmark dependencies are as below:

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile('com.android.support.test.espresso:espresso-
core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-
annotations'
    })
compile 'com.android.support:appcompat-v7:25.3.1'
testCompile 'junit:junit:4.12'
}

Whole project gradle file：

buildscript {
    repositories {
        jcenter()
        google()
    }
dependencies {
    classpath 'com.android.tools.build:gradle:3.0.1'

    // NOTE: Do not place your application dependencies here; they belong
    // in the individual module build.gradle files
}
}
allprojects {
    repositories {
        jcenter()
        google()
    }
}
task clean(type: Delete) {
    delete rootProject.buildDir
}

dependencies {
}

and when building dl4j module in Android Studio I got an error:

Error:java.lang.RuntimeException: java.lang.RuntimeException: com.android.builder.dexing.DexArchiveMergerException: Unable to merge dex

Error:com.android.dex.DexException: Multiple dex files define Ledu/umd/cs/findbugs/annotations/NonNull;

How can I fix this?

Answer 1

As the error message says there are multiple definitions for some classes. I faced the same problem and was able to solve it by looking at the dependency tree.

If you run

./gradlew app:dependencies

in the Android studio terminal, you will get a dependency tree. You will find

com.google.code.findbugs:annotations:2.0.1

This library is required for testing and need not be packed with your apk. You can exclude it from your dependencies like this:

compile('org.nd4j:nd4j-native:0.9.1') {
    exclude group: 'com.google.code.findbugs', module: 'annotations'

}

compile('org.nd4j:nd4j-native:0.9.1:android-x86')
        {
            exclude group: 'com.google.code.findbugs', module: 'annotations'

        }
compile('org.nd4j:nd4j-native:0.9.1:android-arm')
        {
            exclude group: 'com.google.code.findbugs', module: 'annotations'

        }

Now try to build and see if it works.