我正在尝试从https://android.googlesource.com/platform/frameworks/volley/构建最新版本的Volley到.jar。当我进入git文件夹并运行gradle build --stacktrace时，我收到以下错误：
* 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
因此，构建过程失败，因为javadoc无法生成。我已经四处寻找并且无法找到解决方案，所以任何反馈都会受到赞赏。