Android Studio :Null pointer exception when assembleDebugUnitTest gradle task is run

Question

I am trying to run a simple JUNIT test for a test class in android studio. Build goes fine. When i try to run the JUNIT test i get the following error

*

Execution failed for task ':app:mockableAndroidJar'.
> java.lang.NullPointerException (no error message)

*

When i dumped the stacktrace i get the following. I am clueless as to why this is happening.

:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:mockableAndroidJar'.
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteAc
tionsTaskExecuter.java:69)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTa
skExecuter.java:46)
        at org.gradle.api.internal.tasks.execution.PostExecutionAnalysisTaskExecuter.execute(PostExecu
tionAnalysisTaskExecuter.java:35)
        at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskEx
ecuter.java:64)
        at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecut
er.java:58)
        at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptyS
ourceFilesTaskExecuter.java:42)
        at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithN
oActionsExecuter.java:52)
        at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecut
er.java:53)
        at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMost
OnceTaskExecuter.java:43)
        at org.gradle.api.internal.AbstractTask.executeWithoutThrowingTaskFailure(AbstractTask.java:31
0)
        at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.executeTask(Abst
ractTaskPlanExecutor.java:79)
        at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.processTask(Abst
ractTaskPlanExecutor.java:63)
        at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.run(AbstractTask
PlanExecutor.java:51)
        at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.process(DefaultTaskPlanExecutor.java
:23)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.ja
va:88)
        at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:3
7)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:62)
        at org.gradle.execution.DefaultBuildExecuter.access$200(DefaultBuildExecuter.java:23)
        at org.gradle.execution.DefaultBuildExecuter$2.proceed(DefaultBuildExecuter.java:68)
        at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32)

        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:62)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:55)
        at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:14
9)
        at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:106)
        at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:86)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter$DefaultBuildController.run(InProcessB
uildActionExecuter.java:90)
        at org.gradle.tooling.internal.provider.ExecuteBuildActionRunner.run(ExecuteBuildActionRunner.
java:28)
        at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.
java:41)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.
java:28)
        at org.gradle.launcher.exec.DaemonUsageSuggestingBuildActionExecuter.execute(DaemonUsageSugges
tingBuildActionExecuter.java:50)
        at org.gradle.launcher.exec.DaemonUsageSuggestingBuildActionExecuter.execute(DaemonUsageSugges
tingBuildActionExecuter.java:27)
        at org.gradle.launcher.cli.RunBuildAction.run(RunBuildAction.java:40)
        at org.gradle.internal.Actions$RunnableActionAdapter.execute(Actions.java:169)
        at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineAct
ionFactory.java:237)
        at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineAct
ionFactory.java:210)
        at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.jav
a:35)
        at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.jav
a:24)
        at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFacto
ry.java:206)
        at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFacto
ry.java:169)
        at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:33)
        at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:22)
        at org.gradle.launcher.Main.doAction(Main.java:33)
        at org.gradle.launcher.bootstrap.EntryPoint.run(EntryPoint.java:45)
        at org.gradle.launcher.bootstrap.ProcessBootstrap.runNoExit(ProcessBootstrap.java:54)
        at org.gradle.launcher.bootstrap.ProcessBootstrap.run(ProcessBootstrap.java:35)
        at org.gradle.launcher.GradleMain.main(GradleMain.java:23)
        at org.gradle.wrapper.BootstrapMainStarter.start(BootstrapMainStarter.java:33)
        at org.gradle.wrapper.WrapperExecutor.execute(WrapperExecutor.java:130)
        at org.gradle.wrapper.GradleWrapperMain.main(GradleWrapperMain.java:48)
Caused by: java.lang.NullPointerException
        at org.objectweb.asm.MethodWriter.visitMaxs(Unknown Source)
        at org.objectweb.asm.tree.MethodNode.accept(Unknown Source)
        at org.objectweb.asm.tree.MethodNode.accept(Unknown Source)
        at org.objectweb.asm.tree.ClassNode.accept(Unknown Source)
        at com.android.builder.testing.MockableJarGenerator.rewriteClass(MockableJarGenerator.java:134
)
        at com.android.builder.testing.MockableJarGenerator.createMockableJar(MockableJarGenerator.jav
a:91)
        at com.android.build.gradle.internal.tasks.MockableAndroidJarTask.createMockableJar(MockableAn
droidJarTask.groovy:50)
        at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:75)
        at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAct
ion.doExecute(AnnotationProcessingTaskFactory.java:226)
        at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAct
ion.execute(AnnotationProcessingTaskFactory.java:219)
        at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAct
ion.execute(AnnotationProcessingTaskFactory.java:208)
        at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:589)
        at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:572)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteAct
ionsTaskExecuter.java:80)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteAc
tionsTaskExecuter.java:61)
        ... 49 more

Test Environment used:

Environment: 1.2.2 SDK Version : API 21 Build tools 22.0.1 Android Plugin version : 1.2.3 Gradle version : 2.5 JDK : 1.7.0_79

Can you please help me out with this? Is there any problem with my setup?

Build Gradle file:

apply plugin: 'com.android.application'


android {
    compileSdkVersion 21
    buildToolsVersion "22.0.1"

    defaultConfig {
        applicationId "com.example.krishnaswamyna.testmathsapplication"
        minSdkVersion 21
        targetSdkVersion 21
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    compile 'com.android.support:recyclerview-v7:22.2.1'
    compile 'com.android.support:leanback-v17:22.2.1'
    testCompile 'junit:junit:4.12'
    testCompile 'org.mockito:mockito-core:2.0.31-beta'
    testCompile 'org.robolectric:robolectric:3.0'
}

Answer 1

Jus delete the .gradle file in the project

Answer 2

I also had the same issue since a couple of weeks. I saw a hint about the issue being about the SDK from here.

What worked for me was to simply remove the SDK through the SDK Manager and then reinstalling it. You might also have to clean the project and/or invalidate cashes and restart Android Studio, between removing and reinstalling the SDK.

Answer 3

I had the same problem when i installed the Android Studio 2.0.

Uncheck Enable all test artifacts in:

File-> Settings-> Build, Execution, Deployement->Build Tools -> Gradle-> Experimental gradle

Info: link

Answer 4

Clean the build and rebuild the app this might work and fix the issue. This gradle errors might come due to some old edited files just do the above said.