Getting error java.lang.UnSupportedOperationException while obfuscating release apk

Hi, while using proguard and after commenting -dontobfuscate i get this error and I am not able to create obfuscated apk. I have checked for redundant and duplicate libraries. If i add the line -dontobfuscate in proguard rules. Then I am able to create minified apk.

Error:20:10:51.346 [ERROR] [system.err] Note: Some input files use or override a deprecated API.
20:10:51.347 [ERROR] [system.err] Note: Recompile with -Xlint:deprecation for details.
20:10:51.347 [ERROR] [system.err] Note: Some input files use unchecked or unsafe operations.
20:10:51.350 [ERROR] [system.err] Note: Recompile with -Xlint:unchecked for details.
20:12:02.859 [ERROR] [org.gradle.BuildExceptionReporter]
20:12:02.861 [ERROR] [org.gradle.BuildExceptionReporter] FAILURE: Build failed with an exception.
20:12:02.861 [ERROR] [org.gradle.BuildExceptionReporter]
20:12:02.862 [ERROR] [org.gradle.BuildExceptionReporter] * What went wrong:
20:12:02.863 [ERROR] [org.gradle.BuildExceptionReporter] Execution failed for task ':app:transformClassesWithMultidexlistForRelease'.
20:12:02.863 [ERROR] [org.gradle.BuildExceptionReporter] > java.lang.UnsupportedOperationException (no error message)
20:12:02.865 [ERROR] [org.gradle.BuildExceptionReporter]
20:12:02.865 [ERROR] [org.gradle.BuildExceptionReporter] * Exception is:
20:12:02.866 [ERROR] [org.gradle.BuildExceptionReporter] org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:transformClassesWithMultidexlistForRelease'.
20:12:02.866 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:69)
20:12:02.866 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:46)
20:12:02.866 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.tasks.execution.PostExecutionAnalysisTaskExecuter.execute(PostExecutionAnalysisTaskExecuter.java:35)
20:12:02.866 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:66)
20:12:02.866 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58)
20:12:02.867 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:52)
20:12:02.867 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52)
20:12:02.867 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:53)
20:12:02.867 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
20:12:02.867 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:203)
20:12:02.867 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:185)
20:12:02.867 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.processTask(AbstractTaskPlanExecutor.java:66)
20:12:02.867 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.run(AbstractTaskPlanExecutor.java:50)
20:12:02.867 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.process(DefaultTaskPlanExecutor.java:25)
20:12:02.867 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:110)
20:12:02.867 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:37)
20:12:02.868 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
20:12:02.868 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.DefaultBuildExecuter.access$000(DefaultBuildExecuter.java:23)
20:12:02.868 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.DefaultBuildExecuter$1.proceed(DefaultBuildExecuter.java:43)
20:12:02.868 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32)
20:12:02.868 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
20:12:02.868 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:30)
20:12:02.868 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.initialization.DefaultGradleLauncher$4.run(DefaultGradleLauncher.java:153)
20:12:02.868 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.internal.Factories$1.create(Factories.java:22)
20:12:02.868 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:91)
20:12:02.868 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:53)
20:12:02.868 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:150)
20:12:02.869 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.initialization.DefaultGradleLauncher.access$200(DefaultGradleLauncher.java:32)
20:12:02.869 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.initialization.DefaultGradleLauncher$1.create(DefaultGradleLauncher.java:98)
20:12:02.869 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.initialization.DefaultGradleLauncher$1.create(DefaultGradleLauncher.java:92)
20:12:02.869 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:91)
20:12:02.869 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:63)
20:12:02.869 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:92)
20:12:02.869 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:83)
20:12:02.869 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.exec.InProcessBuildActionExecuter$DefaultBuildController.run(InProcessBuildActionExecuter.java:99)
20:12:02.869 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.tooling.internal.provider.runner.BuildModelActionRunner.run(BuildModelActionRunner.java:46)
20:12:02.869 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
20:12:02.870 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.tooling.internal.provider.runner.SubscribableBuildActionRunner.run(SubscribableBuildActionRunner.java:58)
20:12:02.878 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
20:12:02.878 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:48)
20:12:02.878 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:30)
20:12:02.879 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.exec.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:81)
20:12:02.879 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.exec.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:46)
20:12:02.879 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.ExecuteBuild.doBuild(ExecuteBuild.java:52)
20:12:02.880 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
20:12:02.880 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
20:12:02.880 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.WatchForDisconnection.execute(WatchForDisconnection.java:37)
20:12:02.880 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
20:12:02.881 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.ResetDeprecationLogger.execute(ResetDeprecationLogger.java:26)
20:12:02.881 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
20:12:02.881 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.RequestStopIfSingleUsedDaemon.execute(RequestStopIfSingleUsedDaemon.java:34)
20:12:02.881 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
20:12:02.881 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:74)
20:12:02.881 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:72)
20:12:02.881 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.util.Swapper.swap(Swapper.java:38)
20:12:02.882 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.ForwardClientInput.execute(ForwardClientInput.java:72)
20:12:02.882 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
20:12:02.882 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.health.DaemonHealthTracker.execute(DaemonHealthTracker.java:47)
20:12:02.882 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
20:12:02.882 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.LogToClient.doBuild(LogToClient.java:60)
20:12:02.882 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
20:12:02.882 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
20:12:02.882 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.EstablishBuildEnvironment.doBuild(EstablishBuildEnvironment.java:72)
20:12:02.883 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
20:12:02.883 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
20:12:02.883 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.health.HintGCAfterBuild.execute(HintGCAfterBuild.java:41)
20:12:02.883 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
20:12:02.883 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.exec.StartBuildOrRespondWithBusy$1.run(StartBuildOrRespondWithBusy.java:50)
20:12:02.883 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.launcher.daemon.server.DaemonStateCoordinator$1.run(DaemonStateCoordinator.java:237)
20:12:02.883 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:54)
20:12:02.883 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.internal.concurrent.StoppableExecutorImpl$1.run(StoppableExecutorImpl.java:40)
20:12:02.883 [ERROR] [org.gradle.BuildExceptionReporter] Caused by: java.lang.UnsupportedOperationException
20:12:02.883 [ERROR] [org.gradle.BuildExceptionReporter] at com.android.ide.common.process.ProcessInfoBuilder$JavaProcessInfoImpl.getExecutable(ProcessInfoBuilder.java:349)
20:12:02.883 [ERROR] [org.gradle.BuildExceptionReporter] at com.android.build.gradle.internal.process.GradleProcessResult.buildProcessException(GradleProcessResult.java:74)
20:12:02.884 [ERROR] [org.gradle.BuildExceptionReporter] at com.android.build.gradle.internal.process.GradleProcessResult.assertNormalExitValue(GradleProcessResult.java:49)
20:12:02.884 [ERROR] [org.gradle.BuildExceptionReporter] at com.android.builder.core.AndroidBuilder.createMainDexList(AndroidBuilder.java:1426)
20:12:02.884 [ERROR] [org.gradle.BuildExceptionReporter] at com.android.build.gradle.internal.transforms.MultiDexTransform.callDx(MultiDexTransform.java:309)
20:12:02.884 [ERROR] [org.gradle.BuildExceptionReporter] at com.android.build.gradle.internal.transforms.MultiDexTransform.computeList(MultiDexTransform.java:265)
20:12:02.884 [ERROR] [org.gradle.BuildExceptionReporter] at com.android.build.gradle.internal.transforms.MultiDexTransform.transform(MultiDexTransform.java:186)
20:12:02.884 [ERROR] [org.gradle.BuildExceptionReporter] at com.android.build.gradle.internal.pipeline.TransformTask$2.call(TransformTask.java:178)
20:12:02.884 [ERROR] [org.gradle.BuildExceptionReporter] at com.android.build.gradle.internal.pipeline.TransformTask$2.call(TransformTask.java:174)
20:12:02.884 [ERROR] [org.gradle.BuildExceptionReporter] at com.android.builder.profile.ThreadRecorder.record(ThreadRecorder.java:156)
20:12:02.884 [ERROR] [org.gradle.BuildExceptionReporter] at com.android.build.gradle.internal.pipeline.TransformTask.transform(TransformTask.java:173)
20:12:02.885 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:75)
20:12:02.885 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$IncrementalTaskAction.doExecute(AnnotationProcessingTaskFactory.java:245)
20:12:02.885 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAction.execute(AnnotationProcessingTaskFactory.java:221)
20:12:02.885 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$IncrementalTaskAction.execute(AnnotationProcessingTaskFactory.java:232)
20:12:02.885 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAction.execute(AnnotationProcessingTaskFactory.java:210)
20:12:02.885 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:80)
20:12:02.885 [ERROR] [org.gradle.BuildExceptionReporter] at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:61)
20:12:02.885 [ERROR] [org.gradle.BuildExceptionReporter] ... 70 more
20:12:02.885 [ERROR] [org.gradle.BuildExceptionReporter]