生成签名的 apk/bundle 时任务“：app：transformClassesAndResourcesWithR8ForRelease”执行失败

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【中文标题】生成签名的 apk/bundle 时任务“：app：transformClassesAndResourcesWithR8ForRelease”执行失败【英文标题】：Execution failed for task ':app:transformClassesAndResourcesWithR8ForRelease' while generating signed apk/bundle 【发布时间】：2019-09-27 07:20:22 【问题描述】：

程序编译良好，我可以生成未签名的 apk。但是"Execution failed for task ':app:transformClassesAndResourcesWithR8ForRelease'"while 生成签名的apk

我已经设置了multiDexEnabled = true 和android.enableR8 = true。即使android.enableR8 = false 也不起作用。 

org.gradle.execution.MultipleBuildFailures: Build completed with 1 failures.
    at org.gradle.initialization.DefaultGradleLauncher$ExecuteTasks.run(DefaultGradleLauncher.java:386)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:301)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:293)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:175)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:91)
    at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
    at org.gradle.initialization.DefaultGradleLauncher.runTasks(DefaultGradleLauncher.java:247)
    at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:159)
    at org.gradle.initialization.DefaultGradleLauncher.executeTasks(DefaultGradleLauncher.java:134)
    at org.gradle.internal.invocation.GradleBuildController$1.execute(GradleBuildController.java:58)
    at org.gradle.internal.invocation.GradleBuildController$1.execute(GradleBuildController.java:55)
    at org.gradle.internal.invocation.GradleBuildController$3.create(GradleBuildController.java:82)
    at org.gradle.internal.invocation.GradleBuildController$3.create(GradleBuildController.java:75)
    at org.gradle.internal.work.DefaultWorkerLeaseService.withLocks(DefaultWorkerLeaseService.java:183)
    at org.gradle.internal.work.StopShieldingWorkerLeaseService.withLocks(StopShieldingWorkerLeaseService.java:40)
    at org.gradle.internal.invocation.GradleBuildController.doBuild(GradleBuildController.java:75)
    at org.gradle.internal.invocation.GradleBuildController.run(GradleBuildController.java:55)
    at org.gradle.tooling.internal.provider.runner.BuildModelActionRunner.run(BuildModelActionRunner.java:54)
    at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
    at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
    at org.gradle.launcher.exec.BuildOutcomeReportingBuildActionRunner.run(BuildOutcomeReportingBuildActionRunner.java:58)
    at org.gradle.tooling.internal.provider.ValidatingBuildActionRunner.run(ValidatingBuildActionRunner.java:32)
    at org.gradle.launcher.exec.BuildCompletionNotifyingBuildActionRunner.run(BuildCompletionNotifyingBuildActionRunner.java:39)
    at org.gradle.launcher.exec.RunAsBuildOperationBuildActionRunner$3.call(RunAsBuildOperationBuildActionRunner.java:49)
    at org.gradle.launcher.exec.RunAsBuildOperationBuildActionRunner$3.call(RunAsBuildOperationBuildActionRunner.java:44)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:315)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:305)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:175)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor.call(DefaultBuildOperationExecutor.java:101)
    at org.gradle.internal.operations.DelegatingBuildOperationExecutor.call(DelegatingBuildOperationExecutor.java:36)
    at org.gradle.launcher.exec.RunAsBuildOperationBuildActionRunner.run(RunAsBuildOperationBuildActionRunner.java:44)
    at org.gradle.launcher.exec.InProcessBuildActionExecuter$1.transform(InProcessBuildActionExecuter.java:49)
    at org.gradle.launcher.exec.InProcessBuildActionExecuter$1.transform(InProcessBuildActionExecuter.java:46)
    at org.gradle.composite.internal.DefaultRootBuildState.run(DefaultRootBuildState.java:78)
    at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:46)
    at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:31)
    at org.gradle.launcher.exec.BuildTreeScopeBuildActionExecuter.execute(BuildTreeScopeBuildActionExecuter.java:42)
    at org.gradle.launcher.exec.BuildTreeScopeBuildActionExecuter.execute(BuildTreeScopeBuildActionExecuter.java:28)
    at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:78)
    at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:52)
    at org.gradle.tooling.internal.provider.SubscribableBuildActionExecuter.execute(SubscribableBuildActionExecuter.java:59)
    at org.gradle.tooling.internal.provider.SubscribableBuildActionExecuter.execute(SubscribableBuildActionExecuter.java:36)
    at org.gradle.tooling.internal.provider.SessionScopeBuildActionExecuter.execute(SessionScopeBuildActionExecuter.java:68)
    at org.gradle.tooling.internal.provider.SessionScopeBuildActionExecuter.execute(SessionScopeBuildActionExecuter.java:38)
    at org.gradle.tooling.internal.provider.GradleThreadBuildActionExecuter.execute(GradleThreadBuildActionExecuter.java:37)
    at org.gradle.tooling.internal.provider.GradleThreadBuildActionExecuter.execute(GradleThreadBuildActionExecuter.java:26)
    at org.gradle.tooling.internal.provider.ParallelismConfigurationBuildActionExecuter.execute(ParallelismConfigurationBuildActionExecuter.java:43)
    at org.gradle.tooling.internal.provider.ParallelismConfigurationBuildActionExecuter.execute(ParallelismConfigurationBuildActionExecuter.java:29)
    at org.gradle.tooling.internal.provider.StartParamsValidatingActionExecuter.execute(StartParamsValidatingActionExecuter.java:60)
    at org.gradle.tooling.internal.provider.StartParamsValidatingActionExecuter.execute(StartParamsValidatingActionExecuter.java:32)
    at org.gradle.tooling.internal.provider.SessionFailureReportingActionExecuter.execute(SessionFailureReportingActionExecuter.java:55)
    at org.gradle.tooling.internal.provider.SessionFailureReportingActionExecuter.execute(SessionFailureReportingActionExecuter.java:41)
    at org.gradle.tooling.internal.provider.SetupLoggingActionExecuter.execute(SetupLoggingActionExecuter.java:48)
    at org.gradle.tooling.internal.provider.SetupLoggingActionExecuter.execute(SetupLoggingActionExecuter.java:32)
    at org.gradle.launcher.daemon.server.exec.ExecuteBuild.doBuild(ExecuteBuild.java:67)
    at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
    at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:104)
    at org.gradle.launcher.daemon.server.exec.WatchForDisconnection.execute(WatchForDisconnection.java:37)
    at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:104)
    at org.gradle.launcher.daemon.server.exec.ResetDeprecationLogger.execute(ResetDeprecationLogger.java:26)
    at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:104)
    at org.gradle.launcher.daemon.server.exec.RequestStopIfSingleUsedDaemon.execute(RequestStopIfSingleUsedDaemon.java:34)
    at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:104)
    at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:74)
    at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:72)
    at org.gradle.util.Swapper.swap(Swapper.java:38)
    at org.gradle.launcher.daemon.server.exec.ForwardClientInput.execute(ForwardClientInput.java:72)
    at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:104)
    at org.gradle.launcher.daemon.server.exec.LogAndCheckHealth.execute(LogAndCheckHealth.java:55)
    at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:104)
    at org.gradle.launcher.daemon.server.exec.LogToClient.doBuild(LogToClient.java:62)
    at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
    at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:104)
    at org.gradle.launcher.daemon.server.exec.EstablishBuildEnvironment.doBuild(EstablishBuildEnvironment.java:81)
    at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
    at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:104)
    at org.gradle.launcher.daemon.server.exec.StartBuildOrRespondWithBusy$1.run(StartBuildOrRespondWithBusy.java:50)
    at org.gradle.launcher.daemon.server.DaemonStateCoordinator$1.run(DaemonStateCoordinator.java:295)
    at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
    at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:transformClassesAndResourcesWithR8ForRelease'.
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:95)
    at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:91)
    at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:57)
    at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:119)
    at org.gradle.api.internal.tasks.execution.ResolvePreviousStateExecuter.execute(ResolvePreviousStateExecuter.java:43)
    at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:93)
    at org.gradle.api.internal.tasks.execution.FinalizePropertiesTaskExecuter.execute(FinalizePropertiesTaskExecuter.java:45)
    at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:94)
    at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:56)
    at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:55)
    at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:36)
    at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.executeTask(EventFiringTaskExecuter.java:67)
    at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:52)
    at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:49)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:315)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:305)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:175)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor.call(DefaultBuildOperationExecutor.java:101)
    at org.gradle.internal.operations.DelegatingBuildOperationExecutor.call(DelegatingBuildOperationExecutor.java:36)
    at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter.execute(EventFiringTaskExecuter.java:49)
    at org.gradle.execution.plan.LocalTaskNodeExecutor.execute(LocalTaskNodeExecutor.java:43)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:355)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:343)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:336)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:322)
    at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker$1.execute(DefaultPlanExecutor.java:134)
    at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker$1.execute(DefaultPlanExecutor.java:129)
    at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.execute(DefaultPlanExecutor.java:202)
    at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.executeNextNode(DefaultPlanExecutor.java:193)
    at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.run(DefaultPlanExecutor.java:129)
    ... 6 more
Caused by: java.lang.NullPointerException
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at java.util.concurrent.ForkJoinTask.getThrowableException(ForkJoinTask.java:598)
    at java.util.concurrent.ForkJoinTask.get(ForkJoinTask.java:1005)
    at com.android.tools.r8.utils.ThreadUtils.awaitFutures(ThreadUtils.java:21)
    at com.android.tools.r8.ir.conversion.CallGraph.forEachMethod(CallGraph.java:472)
    at com.android.tools.r8.ir.conversion.IRConverter.optimize(IRConverter.java:549)
    at com.android.tools.r8.R8.run(R8.java:508)
    at com.android.tools.r8.R8.run(R8.java:251)
    at com.android.tools.r8.R8.lambda$runForTesting$1(R8.java:242)
    at com.android.tools.r8.utils.ExceptionUtils.withCompilationHandler(ExceptionUtils.java:62)
    at com.android.tools.r8.utils.ExceptionUtils.withR8CompilationHandler(ExceptionUtils.java:50)
    at com.android.tools.r8.R8.runForTesting(R8.java:238)
    at com.android.tools.r8.R8.run(R8.java:148)
    at com.android.builder.dexing.R8Tool.runR8(r8Tool.kt:189)
    at com.android.build.gradle.internal.transforms.R8Transform.transform(R8Transform.kt:260)
    at com.android.build.gradle.internal.pipeline.TransformTask$2.call(TransformTask.java:239)
    at com.android.build.gradle.internal.pipeline.TransformTask$2.call(TransformTask.java:235)
    at com.android.builder.profile.ThreadRecorder.record(ThreadRecorder.java:102)
    at com.android.build.gradle.internal.pipeline.TransformTask.transform(TransformTask.java:230)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:73)
    at org.gradle.api.internal.project.taskfactory.IncrementalTaskAction.doExecute(IncrementalTaskAction.java:47)
    at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:41)
    at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:28)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$2.run(ExecuteActionsTaskExecuter.java:284)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:301)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:293)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:175)
    at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:91)
    at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:273)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:258)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.access$200(ExecuteActionsTaskExecuter.java:67)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$TaskExecution.execute(ExecuteActionsTaskExecuter.java:145)
    at org.gradle.internal.execution.impl.steps.ExecuteStep.execute(ExecuteStep.java:49)
    at org.gradle.internal.execution.impl.steps.CancelExecutionStep.execute(CancelExecutionStep.java:34)
    at org.gradle.internal.execution.impl.steps.TimeoutStep.executeWithoutTimeout(TimeoutStep.java:69)
    at org.gradle.internal.execution.impl.steps.TimeoutStep.execute(TimeoutStep.java:49)
    at org.gradle.internal.execution.impl.steps.CatchExceptionStep.execute(CatchExceptionStep.java:33)
    at org.gradle.internal.execution.impl.steps.CreateOutputsStep.execute(CreateOutputsStep.java:50)
    at org.gradle.internal.execution.impl.steps.SnapshotOutputStep.execute(SnapshotOutputStep.java:43)
    at org.gradle.internal.execution.impl.steps.SnapshotOutputStep.execute(SnapshotOutputStep.java:29)
    at org.gradle.internal.execution.impl.steps.CacheStep.executeWithoutCache(CacheStep.java:134)
    at org.gradle.internal.execution.impl.steps.CacheStep.lambda$execute$3(CacheStep.java:83)
    at java.util.Optional.orElseGet(Optional.java:267)
    at org.gradle.internal.execution.impl.steps.CacheStep.execute(CacheStep.java:82)
    at org.gradle.internal.execution.impl.steps.CacheStep.execute(CacheStep.java:36)
    at org.gradle.internal.execution.impl.steps.PrepareCachingStep.execute(PrepareCachingStep.java:33)
    at org.gradle.internal.execution.impl.steps.StoreSnapshotsStep.execute(StoreSnapshotsStep.java:38)
    at org.gradle.internal.execution.impl.steps.StoreSnapshotsStep.execute(StoreSnapshotsStep.java:23)
    at org.gradle.internal.execution.impl.steps.SkipUpToDateStep.executeBecause(SkipUpToDateStep.java:96)
    at org.gradle.internal.execution.impl.steps.SkipUpToDateStep.lambda$execute$0(SkipUpToDateStep.java:89)
    at java.util.Optional.map(Optional.java:215)
    at org.gradle.internal.execution.impl.steps.SkipUpToDateStep.execute(SkipUpToDateStep.java:52)
    at org.gradle.internal.execution.impl.steps.SkipUpToDateStep.execute(SkipUpToDateStep.java:36)
    at org.gradle.internal.execution.impl.DefaultWorkExecutor.execute(DefaultWorkExecutor.java:34)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:91)
    ... 35 more
    Suppressed: java.util.concurrent.ExecutionException: java.lang.NullPointerException
        at java.util.concurrent.ForkJoinTask.get(ForkJoinTask.java:1006)
        ... 92 more
    [CIRCULAR REFERENCE:java.lang.NullPointerException]
Caused by: java.lang.NullPointerException
    at com.android.tools.r8.ir.optimize.CodeRewriter.workaroundExceptionTargetingLoopHeaderBug(CodeRewriter.java:3839)
    at com.android.tools.r8.ir.conversion.IRConverter.performRegisterAllocation(IRConverter.java:1251)
    at com.android.tools.r8.ir.conversion.IRConverter.finalizeToDex(IRConverter.java:1207)
    at com.android.tools.r8.ir.conversion.IRConverter.finalizeIR(IRConverter.java:1181)
    at com.android.tools.r8.ir.conversion.IRConverter.rewriteCode(IRConverter.java:1122)
    at com.android.tools.r8.ir.conversion.IRConverter.processMethod(IRConverter.java:805)
    at com.android.tools.r8.ir.conversion.IRConverter.lambda$optimize$5(IRConverter.java:551)
    at com.android.tools.r8.ir.conversion.CallGraph.lambda$forEachMethod$6(CallGraph.java:468)
    at java.util.concurrent.ForkJoinTask$AdaptedCallable.exec(ForkJoinTask.java:1424)
    at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
    at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
    at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
    at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)

这是我的 build.gradle（模块：app）

apply plugin: 'com.android.application'
apply plugin: 'com.google.gms.google-services'

android 
    compileSdkVersion 28
    buildToolsVersion '28.0.3'
    defaultConfig 
        applicationId "com.microsoft.abiram.gkm"
        minSdkVersion 18
        targetSdkVersion 28
        versionCode 26
        versionName "1.7"
        multiDexEnabled true
        vectorDrawables.useSupportLibrary = true
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    
    buildTypes 
        release 
            minifyEnabled true
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        
    


dependencies 
    implementation fileTree(include: ['*.jar'], dir: 'libs')
    implementation 'androidx.appcompat:appcompat:1.0.2'

    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test:runner:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
    implementation 'com.google.firebase:firebase-core:16.0.8'
    implementation 'io.branch.sdk.android:library:3.1.2'
    implementation 'com.google.firebase:firebase-auth:16.2.1'
    implementation 'com.google.android.gms:play-services-auth:16.0.1'
    implementation 'pl.droidsonroids.gif:android-gif-drawable:1.2.16'
    implementation 'com.google.firebase:firebase-config:16.5.0'
    implementation 'com.google.firebase:firebase-messaging:17.6.0'
    implementation 'com.google.android.material:material:1.1.0-alpha05'
    implementation 'com.github.paolorotolo:expandableheightlistview:1.0.0'
    implementation 'com.github.GrenderG:Toasty:1.4.1'
    implementation 'com.getkeepsafe.taptargetview:taptargetview:1.12.0'
    implementation 'com.github.AppIntro:AppIntro:v5.1.0'
    implementation 'com.tapadoo.android:alerter:4.0.2'
    implementation 'androidx.cardview:cardview:1.0.0'
    implementation 'com.gdacciaro:iosdialog:1.0.3'

build.grade（项目）

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript 

    repositories 
        google()
        jcenter()
        mavenCentral()
    
    dependencies 
        classpath 'com.android.tools.build:gradle:3.4.0'


        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
        classpath 'com.google.gms:google-services:4.2.0'
    


allprojects 
    repositories 
        google()
        jcenter()
        mavenCentral()
        maven  url "https://jitpack.io" 
    


task clean(type: Delete) 
    delete rootProject.buildDir


subprojects
        
            project.configurations.all 
                resolutionStrategy.eachDependency  details ->
                    if (details.requested.group == 'com.android.support'
                            && !details.requested.name.contains('multidex') ) 
                        details.useVersion "26.1.0"

gradle.properties

# Project-wide Gradle settings.
# IDE (e.g. Android Studio) users:
# Gradle settings configured through the IDE *will override*
# any settings specified in this file.
# For more details on how to configure your build environment visit
# http://www.gradle.org/docs/current/userguide/build_environment.html
# Specifies the JVM arguments used for the daemon process.
# The setting is particularly useful for tweaking memory settings.
org.gradle.jvmargs=-Xmx1536m
android.useAndroidX=true
android.enableJetifier=true
android.enableR8 = true
multiDexEnabled = true
# When configured, Gradle will run in incubating parallel mode.
# This option should only be used with decoupled projects. More details, visit
# http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects
# org.gradle.parallel=true

【问题讨论】：

你有什么解决办法吗？ 【参考方案1】：

问题不在于构建，而在于代码。我通过替换

解决了这个问题 
    catch (MalformedURLException paramVarArgs1)
        
            for (;;)  //which can only exit by throwing an exception
        
        catch (IOException paramVarArgs1)
        

            for (;;)  //which can only exit by throwing an exception

到

  catch (MalformedURLException paramVarArgs1)
        
            System.out.println("Caught in main(MalformedURLException)."+paramVarArgs1); //anything that can throw an exception
        
        catch (IOException paramVarArgs1)
        

            System.out.println("Caught in main(IOException)."+paramVarArgs1); //anything that can throw an exception

【讨论】：

你到底为什么在 catch 子句中写了那行 for(;;)？【参考方案2】：

在我的情况下添加

android.enableR8 = false

在gradle.properties 中修复了问题。 这是一个临时解决方案，不应被视为救世主解决方案。

【讨论】：

R8 是新的 android 收缩器，默认使用它来代替 proguard。所以你刚刚禁用了 R8，这意味着 gradle 将使用 proguard，这就是为什么你不再收到任何关于 R8 的问题。【参考方案3】：

其实新版firebase库有问题 按照这些步骤对我有用，

    从“node_modules”中手动删除“react-native-firebase”文件夹。 从终端./gradlew clean转到android文件夹运行此命令 再次尝试生成 apk。

【讨论】：

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