Volley .jar Gradle Build Failure

Estoy intentando build la última versión de Volley desde https://android.googlesource.com/platform/frameworks/volley/ en un .jar. Cuando gradle build --stacktrace en la carpeta git y ejecuto gradle build --stacktrace , obtengo el siguiente error:

 * Exception is: org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':javadoc'. 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:64) at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58) at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:42) 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.api.internal.AbstractTask.executeWithoutThrowingTaskFailure(AbstractTask.java:305) at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.executeTask(AbstractTaskPlanExecutor.java:79) at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.processTask(AbstractTaskPlanExecutor.java:63) at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.run(AbstractTaskPlanExecutor.java:51) at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.process(DefaultTaskPlanExecutor.java:23) at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:88) at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:29) at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:62) at org.gradle.execution.DefaultBuildExecuter.access$200(DefaultBuildExecuter.java:23) at org.gradle.execution.DefaultBuildExecuter$2.proceed(DefaultBuildExecuter.java:68) at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32) at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:62) at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:55) at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:149) at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:106) at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:86) at org.gradle.launcher.exec.InProcessBuildActionExecuter$DefaultBuildController.run(InProcessBuildActionExecuter.java:80) at org.gradle.launcher.cli.ExecuteBuildAction.run(ExecuteBuildAction.java:33) at org.gradle.launcher.cli.ExecuteBuildAction.run(ExecuteBuildAction.java:24) at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:36) at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:26) at org.gradle.launcher.cli.RunBuildAction.run(RunBuildAction.java:51) at org.gradle.internal.Actions$RunnableActionAdapter.execute(Actions.java:171) at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:237) at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:210) at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.java:35) at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.java:24) at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:206) at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:169) at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:33) at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:22) at org.gradle.launcher.Main.doAction(Main.java:33) at org.gradle.launcher.bootstrap.EntryPoint.run(EntryPoint.java:45) at org.gradle.launcher.bootstrap.ProcessBootstrap.runNoExit(ProcessBootstrap.java:54) at org.gradle.launcher.bootstrap.ProcessBootstrap.run(ProcessBootstrap.java:35) at org.gradle.launcher.GradleMain.main(GradleMain.java:23) Caused by: org.gradle.api.GradleException: Javadoc generation failed. Generated Javadoc options file (useful for troubleshooting): '/Users/xxxxx/git/volley/build/tmp/javadoc/javadoc.options' at org.gradle.api.tasks.javadoc.internal.JavadocGenerator.execute(JavadocGenerator.java:55) at org.gradle.api.tasks.javadoc.internal.JavadocGenerator.execute(JavadocGenerator.java:31) at org.gradle.api.tasks.javadoc.Javadoc.executeExternalJavadoc(Javadoc.java:140) at org.gradle.api.tasks.javadoc.Javadoc.generate(Javadoc.java:128) at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:63) at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAction.doExecute(AnnotationProcessingTaskFactory.java:218) at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAction.execute(AnnotationProcessingTaskFactory.java:211) at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAction.execute(AnnotationProcessingTaskFactory.java:200) at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:579) at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:562) at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:80) at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:61) ... 44 more Caused by: org.gradle.process.internal.ExecException: Process 'command '/Library/Java/JavaVirtualMachines/jdk1.8.0_25.jdk/Contents/Home/bin/javadoc'' finished with non-zero exit value 1 at org.gradle.process.internal.DefaultExecHandle$ExecResultImpl.assertNormalExitValue(DefaultExecHandle.java:365) at org.gradle.process.internal.DefaultExecAction.execute(DefaultExecAction.java:31) at org.gradle.api.tasks.javadoc.internal.JavadocGenerator.execute(JavadocGenerator.java:52) ... 55 more 

Entonces, el process de compilation falla porque el javadoc no genera. He buscado y no he podido encontrar una solución, por lo que cualquier comentario sería apreciado.