Android Studios RuntimeException: Unexpected exception in dex writer thread

Question

I have been getting this strange error the whole of today - anyone know what is going wrong here?

As far as I know, I have been using the multidex library correctly (the below is from the app.gradle file):

defaultConfig {
    applicationId "com.example.simon"
    minSdkVersion 14
    targetSdkVersion 23
    versionCode 1
    versionName "1.0"
    /*Enabling multidex*/
    multiDexEnabled true
}

dependencies {
    /*    Enabling multidex*/
    compile 'com.android.support:multidex:1.0.1'
}

My top level gradle file is very basic:

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:1.3.0'
        classpath 'com.google.gms:google-services:1.3.1'
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        jcenter()
    }
}

Error:

    Executing tasks: [:app:generateDebugSources,
:app:generateDebugAndroidTestSources]

Parallel execution with configuration on demand is an incubating
feature.
:app:preBuild UP-TO-DATE
:app:preDebugBuild UP-TO-DATE
:app:checkDebugManifest
:app:preReleaseBuild UP-TO-DATE
:app:prepareComAndroidSupportAppcompatV72301Library UP-TO-DATE
:app:prepareComAndroidSupportCardviewV72301Library UP-TO-DATE
:app:prepareComAndroidSupportDesign2301Library UP-TO-DATE
:app:prepareComAndroidSupportMultidex101Library UP-TO-DATE
:app:prepareComAndroidSupportPaletteV72301Library UP-TO-DATE
:app:prepareComAndroidSupportRecyclerviewV72301Library UP-TO-DATE
:app:prepareComAndroidSupportSupportV42301Library UP-TO-DATE
:app:prepareComDigitsSdkAndroidDigits162Library UP-TO-DATE
:app:prepareComFacebookAndroidFacebookAndroidSdk440Library UP-TO-DATE
:app:prepareComFacebookConcealConceal101Library UP-TO-DATE
:app:prepareComGithubCurioustechizenAndroidAgoLibrary130Library UP-TO-DATE
:app:prepareComGoogleAndroidGmsPlayServicesAppinvite780Library UP-TO-DATE
:app:prepareComGoogleAndroidGmsPlayServicesBase780Library UP-TO-DATE
:app:prepareComGoogleAndroidGmsPlayServicesGcm780Library UP-TO-DATE
:app:prepareComGoogleAndroidGmsPlayServicesLocation780Library UP-TO-DATE
:app:prepareComGoogleAndroidGmsPlayServicesMaps780Library UP-TO-DATE
:app:prepareComTheartofdevEdmodoAndroidImageCropper104Library UP-TO-DATE
:app:prepareComTwitterSdkAndroidTweetComposer080Library UP-TO-DATE
:app:prepareComTwitterSdkAndroidTweetUi131Library UP-TO-DATE
:app:prepareComTwitterSdkAndroidTwitter161Library UP-TO-DATE
:app:prepareComTwitterSdkAndroidTwitterCore141Library UP-TO-DATE
:app:prepareIoFabricSdkAndroidFabric134Library UP-TO-DATE
:app:prepareDebugDependencies
:app:compileDebugAidl UP-TO-DATE
:app:compileDebugRenderscript UP-TO-DATE
:app:generateDebugBuildConfig UP-TO-DATE
:app:generateDebugAssets UP-TO-DATE
:app:mergeDebugAssets UP-TO-DATE
:app:generateDebugResValues UP-TO-DATE
:app:processDebugGoogleServices
:app:generateDebugResources
:app:mergeDebugResources UP-TO-DATE
:app:processDebugManifest UP-TO-DATE
:app:fabricGenerateResourcesDebug
:app:processDebugResources
:app:generateDebugSources
:app:preDebugAndroidTestBuild UP-TO-DATE
:app:prepareDebugAndroidTestDependencies
:app:compileDebugAndroidTestAidl UP-TO-DATE
:app:processDebugAndroidTestManifest UP-TO-DATE
:app:compileDebugAndroidTestRenderscript UP-TO-DATE
:app:generateDebugAndroidTestBuildConfig UP-TO-DATE
:app:generateDebugAndroidTestAssets UP-TO-DATE
:app:mergeDebugAndroidTestAssets UP-TO-DATE
:app:generateDebugAndroidTestResValues UP-TO-DATE
:app:generateDebugAndroidTestResources UP-TO-DATE
:app:mergeDebugAndroidTestResources UP-TO-DATE
:app:processDebugAndroidTestResources UP-TO-DATE
:app:generateDebugAndroidTestSources UP-TO-DATE

BUILD SUCCESSFUL

Total time: 3.913 secs Executing tasks: [:app:assembleDebug]

Parallel execution with configuration on demand is an incubating
feature.
:app:preBuild UP-TO-DATE
:app:preDebugBuild UP-TO-DATE
:app:checkDebugManifest
:app:preReleaseBuild UP-TO-DATE
:app:prepareComAndroidSupportAppcompatV72301Library UP-TO-DATE
:app:prepareComAndroidSupportCardviewV72301Library UP-TO-DATE
:app:prepareComAndroidSupportDesign2301Library UP-TO-DATE
:app:prepareComAndroidSupportMultidex101Library UP-TO-DATE
:app:prepareComAndroidSupportPaletteV72301Library UP-TO-DATE
:app:prepareComAndroidSupportRecyclerviewV72301Library UP-TO-DATE
:app:prepareComAndroidSupportSupportV42301Library UP-TO-DATE
:app:prepareComDigitsSdkAndroidDigits162Library UP-TO-DATE
:app:prepareComFacebookAndroidFacebookAndroidSdk440Library UP-TO-DATE
:app:prepareComGithubCurioustechizenAndroidAgoLibrary130Library UP-TO-DATE
:app:prepareComGoogleAndroidGmsPlayServicesAppinvite780Library UP-TO-DATE
:app:prepareComGoogleAndroidGmsPlayServicesBase780Library UP-TO-DATE
:app:prepareComGoogleAndroidGmsPlayServicesGcm780Library UP-TO-DATE
:app:prepareComGoogleAndroidGmsPlayServicesLocation780Library UP-TO-DATE
:app:prepareComGoogleAndroidGmsPlayServicesMaps780Library UP-TO-DATE
:app:prepareComTheartofdevEdmodoAndroidImageCropper104Library
:app:prepareDebugDependencies
:app:compileDebugAidl UP-TO-DATE
:app:compileDebugRenderscript UP-TO-DATE
:app:generateDebugBuildConfig UP-TO-DATE
:app:generateDebugAssets UP-TO-DATE
:app:mergeDebugAssets UP-TO-DATE
:app:generateDebugResValues UP-TO-DATE
:app:processDebugGoogleServices
:app:generateDebugResources
:app:mergeDebugResources UP-TO-DATE
:app:processDebugManifest UP-TO-DATE
:app:fabricGenerateResourcesDebug
:app:processDebugResources
:app:generateDebugSources
:app:processDebugJavaRes UP-TO-DATE
:app:compileDebugJavaWithJavac UP-TO-DATE
:app:compileDebugNdk UP-TO-DATE
:app:compileDebugSources UP-TO-DATE
:app:collectDebugMultiDexComponents UP-TO-DATE
:app:packageAllDebugClassesForMultiDex UP-TO-DATE
:app:shrinkDebugMultiDexComponents UP-TO-DATE
:app:createDebugMainDexClassList UP-TO-DATE
:app:dexDebugExecuting
tasks: [:app:assembleDebug]

Parallel execution with configuration on demand is an incubating
feature.
:app:preBuild UP-TO-DATE
:app:preDebugBuild UP-TO-DATE
:app:checkDebugManifest
:app:preReleaseBuild UP-TO-DATE
:app:prepareComAndroidSupportAppcompatV72301Library UP-TO-DATE
:app:prepareComAndroidSupportCardviewV72301Library UP-TO-DATE
:app:prepareComAndroidSupportDesign2301Library UP-TO-DATE
:app:prepareComAndroidSupportMultidex101Library UP-TO-DATE
:app:prepareComAndroidSupportPaletteV72301Library UP-TO-DATE
:app:prepareComAndroidSupportRecyclerviewV72301Library UP-TO-DATE
:app:prepareComAndroidSupportSupportV42301Library UP-TO-DATE
:app:prepareComDigitsSdkAndroidDigits162Library UP-TO-DATE
:app:prepareDebugDependencies
:app:compileDebugAidl UP-TO-DATE
:app:compileDebugRenderscript UP-TO-DATE
:app:generateDebugBuildConfig UP-TO-DATE
:app:generateDebugAssets UP-TO-DATE
:app:mergeDebugAssets UP-TO-DATE
:app:generateDebugResValues UP-TO-DATE
:app:processDebugGoogleServices
:app:generateDebugResources
:app:mergeDebugResources UP-TO-DATE
:app:processDebugManifest UP-TO-DATE
:app:fabricGenerateResourcesDebug
:app:processDebugResources
:app:generateDebugSources
:app:processDebugJavaRes UP-TO-DATE
:app:compileDebugJavaWithJavac UP-TO-DATE
:app:compileDebugNdk UP-TO-DATE
:app:compileDebugSources UP-TO-DATE
:app:collectDebugMultiDexComponents UP-TO-DATE
:app:packageAllDebugClassesForMultiDex UP-TO-DATE
:app:shrinkDebugMultiDexComponents UP-TO-DATE
:app:createDebugMainDexClassList UP-TO-DATE
:app:dexDebug AGPBI:
{"kind":"simple","text":"UNEXPECTED TOP-LEVEL
EXCEPTION:","sources":[{}]} AGPBI:
{"kind":"simple","text":"java.lang.RuntimeException: Unexpected
exception in dex writer thread","sources":[{}]} AGPBI:
{"kind":"simple","text":"\tat
com.android.dx.command.dexer.Main.runMultiDex(Main.java:397)","sources":[{}]}
AGPBI: {"kind":"simple","text":"\tat
com.android.dx.command.dexer.Main.run(Main.java:275)","sources":[{}]}
AGPBI: {"kind":"simple","text":"\tat
com.android.dx.command.dexer.Main.main(Main.java:245)","sources":[{}]}
AGPBI: {"kind":"simple","text":"\tat
com.android.dx.command.Main.main(Main.java:106)","sources":[{}]}


 FAILED

FAILURE: Build failed with an exception.

* What went wrong: Execution failed for task ':app:dexDebug'.
com.android.ide.common.process.ProcessException: org.gradle.process.internal.ExecException: Process 'command
'C:\Program Files\Java\jdk1.7.0_76\bin\java.exe'' finished with
non-zero exit value 2

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

BUILD FAILED

Total time: 1 mins 5.426 secs

Answer 1

After googling for a while, I found the problem was that not enough heap was allocated to the dex writer.

I fixed it by putting in the following in my app gradle.build:

android {
    dexOptions {
        incremental true
        javaMaxHeapSize "4g"
    }
}

This option also managed to speed up my gradle build significantly.

Extremely long build with Gradle (Android Studio)

Answer 2

Adding this to my Project level gradle.properties helped -

org.gradle.jvmargs=-Xmx1536m -XX:MaxPermSize=512m -XX:+HeapDumpOnOutOfMemoryError -Dfile.encoding=UTF-8

Answer 3

change your manifist to this

defaultConfig 
{
    applicationId "com.example.simon"
    minSdkVersion 14
    targetSdkVersion 23
    versionCode 1
    versionName "1.0"
    /*Enabling multidex*/
    multiDexEnabled true
}
android {
    dexOptions {
        incremental true
        javaMaxHeapSize "4g"
    }
}

dependencies {
    /*    Enabling multidex*/
       compile 'com.android.support:multidex:1.0.1'
}

and this problem shows when you add the :

/*Enabling multidex*/
    multiDexEnabled true

most of the times. and for more information please tell me the exact thing you didnt undestand