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Android

Posted by dlpuxdzztg
dlpuxdzztg
8,243 Points

Unable to Establish Loopback Connection

Hello.

I ran 'gradlew build' in the Android Studio terminal under the gradlew.bat file in my project and I got an error that said: "java.io.IOException: Unable to establish loopback connection".

Here is alot more info on the error:

org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:testDebugUnitTest'.
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:69)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:46)
        at org.gradle.api.internal.tasks.execution.PostExecutionAnalysisTaskExecuter.execute(PostExecutionAnalysisTaskExecuter.java:35)
        at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:66)
        at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58)
        at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:52)
        at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52)
        at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:53)
        at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:203)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:185)
        at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.processTask(AbstractTaskPlanExecutor.java:66)
        at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.run(AbstractTaskPlanExecutor.java:50)
        at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.process(DefaultTaskPlanExecutor.java:25)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:110)
        at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:37)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
        at org.gradle.execution.DefaultBuildExecuter.access$000(DefaultBuildExecuter.java:23)
        at org.gradle.execution.DefaultBuildExecuter$1.proceed(DefaultBuildExecuter.java:43)
        at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:30)
        at org.gradle.initialization.DefaultGradleLauncher$4.run(DefaultGradleLauncher.java:153)
        at org.gradle.internal.Factories$1.create(Factories.java:22)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:91)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:53)
        at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:150)
        at org.gradle.initialization.DefaultGradleLauncher.access$200(DefaultGradleLauncher.java:32)
        at org.gradle.initialization.DefaultGradleLauncher$1.create(DefaultGradleLauncher.java:98)
        at org.gradle.initialization.DefaultGradleLauncher$1.create(DefaultGradleLauncher.java:92)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:91)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:63)
        at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:92)
        at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:83)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter$DefaultBuildController.run(InProcessBuildActionExecuter.java:99)
        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:48)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:30)
        at org.gradle.launcher.exec.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:81)
        at org.gradle.launcher.exec.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:46)
        at org.gradle.launcher.exec.DaemonUsageSuggestingBuildActionExecuter.execute(DaemonUsageSuggestingBuildActionExecuter.java:51)
        at org.gradle.launcher.exec.DaemonUsageSuggestingBuildActionExecuter.execute(DaemonUsageSuggestingBuildActionExecuter.java:28)
        at org.gradle.launcher.cli.RunBuildAction.run(RunBuildAction.java:43)
        at org.gradle.internal.Actions$RunnableActionAdapter.execute(Actions.java:173)
        at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:239)
        at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:212)
        at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.java:35)
        at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.java:24)
        at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:33)
        at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:22)
        at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:205)
        at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:169)
        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:55)
        at org.gradle.launcher.bootstrap.ProcessBootstrap.run(ProcessBootstrap.java:36)
        at org.gradle.launcher.GradleMain.main(GradleMain.java:23)
        at org.gradle.wrapper.BootstrapMainStarter.start(BootstrapMainStarter.java:30)
        at org.gradle.wrapper.WrapperExecutor.execute(WrapperExecutor.java:129)
        at org.gradle.wrapper.GradleWrapperMain.main(GradleWrapperMain.java:61)
Caused by: org.gradle.api.UncheckedIOException: java.io.IOException: Unable to establish loopback connection
        at org.gradle.internal.UncheckedException.throwAsUncheckedException(UncheckedException.java:43)
        at org.gradle.internal.remote.internal.inet.SocketConnection.<init>(SocketConnection.java:60)
        at org.gradle.internal.remote.internal.inet.SocketConnectCompletion.create(SocketConnectCompletion.java:39)
        at org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection.connect(MessageHubBackedObjectConnection.java:97)
        at org.gradle.api.internal.tasks.testing.worker.ForkingTestClassProcessor.forkProcess(ForkingTestClassProcessor.java:85)
        at org.gradle.api.internal.tasks.testing.worker.ForkingTestClassProcessor.processTestClass(ForkingTestClassProcessor.java:64)
        at org.gradle.api.internal.tasks.testing.processors.RestartEveryNTestClassProcessor.processTestClass(RestartEveryNTestClassProcessor.java:47)
        at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:35)
        at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
        at org.gradle.internal.dispatch.FailureHandlingDispatch.dispatch(FailureHandlingDispatch.java:29)
        at org.gradle.internal.dispatch.AsyncDispatch.dispatchMessages(AsyncDispatch.java:132)
        at org.gradle.internal.dispatch.AsyncDispatch.access$000(AsyncDispatch.java:33)
        at org.gradle.internal.dispatch.AsyncDispatch$1.run(AsyncDispatch.java:72)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:54)
        at org.gradle.internal.concurrent.StoppableExecutorImpl$1.run(StoppableExecutorImpl.java:40)
Caused by: java.io.IOException: Unable to establish loopback connection
        at org.gradle.internal.remote.internal.inet.SocketConnection$SocketInputStream.<init>(SocketConnection.java:142)
        at org.gradle.internal.remote.internal.inet.SocketConnection.<init>(SocketConnection.java:58)
        ... 13 more
Caused by: java.net.SocketException: Permission denied: connect
        ... 15 more

Please help.

1 Answer

Seth Kroger
Seth Kroger
56,413 Points
Seth Kroger
Seth Kroger
56,413 Points

A loopback connection is the computer connecting with itself, i.e. localhost or 127.0.0.1. Did you update or change your firewall recently? Have you tried restarting your PC and trying again?

dlpuxdzztg
dlpuxdzztg
8,243 Points

Well, I do have an internet filter on my computer, even though it was working before.