### Question:
LinuxContainerExecutor extends ContainerExecutor { @Override public void setConf(Configuration conf) { super.setConf(conf); resourcesHandler = ReflectionUtils.newInstance( conf.getClass(YarnConfiguration.NM_LINUX_CONTAINER_RESOURCES_HANDLER, DefaultLCEResourcesHandler.class, LCEResourcesHandler.class), conf); resourcesHandler.setConf(conf); if (conf.get(YarnConfiguration.NM_CONTAINER_EXECUTOR_SCHED_PRIORITY) != null) { containerSchedPriorityIsSet = true; containerSchedPriorityAdjustment = conf .getInt(YarnConfiguration.NM_CONTAINER_EXECUTOR_SCHED_PRIORITY, YarnConfiguration.DEFAULT_NM_CONTAINER_EXECUTOR_SCHED_PRIORITY); } nonsecureLocalUser = conf.get( YarnConfiguration.NM_NONSECURE_MODE_LOCAL_USER_KEY, YarnConfiguration.DEFAULT_NM_NONSECURE_MODE_LOCAL_USER); nonsecureLocalUserPattern = Pattern.compile( conf.get(YarnConfiguration.NM_NONSECURE_MODE_USER_PATTERN_KEY, YarnConfiguration.DEFAULT_NM_NONSECURE_MODE_USER_PATTERN)); containerLimitUsers = conf.getBoolean( YarnConfiguration.NM_NONSECURE_MODE_LIMIT_USERS, YarnConfiguration.DEFAULT_NM_NONSECURE_MODE_LIMIT_USERS); if (!containerLimitUsers) { LOG.warn(YarnConfiguration.NM_NONSECURE_MODE_LIMIT_USERS + ": impersonation without authentication enabled"); } } LinuxContainerExecutor(); @VisibleForTesting  LinuxContainerExecutor(LinuxContainerRuntime linuxContainerRuntime); @Override void setConf(Configuration conf); @Override void init(); @Override void startLocalizer(LocalizerStartContext ctx); @Override int prepareContainer(ContainerStartContext ctx); @VisibleForTesting void buildMainArgs(List<String> command, String user, String appId,
      String locId, InetSocketAddress nmAddr, List<String> localDirs); @Override int launchContainer(ContainerStartContext ctx); @Override int reacquireContainer(ContainerReacquisitionContext ctx); @Override boolean signalContainer(ContainerSignalContext ctx); @Override void deleteAsUser(DeletionAsUserContext ctx); @Override boolean isContainerAlive(ContainerLivenessContext ctx); void mountCgroups(List<String> cgroupKVs, String hierarchy);  }### Answer:
@Test public void testNonSecureRunAsSubmitter() throws Exception { Assume.assumeTrue(shouldRun()); Assume.assumeFalse(UserGroupInformation.isSecurityEnabled()); String expectedRunAsUser = appSubmitter; conf.set(YarnConfiguration.NM_NONSECURE_MODE_LIMIT_USERS, "false"); exec.setConf(conf); File touchFile = new File(workSpace, "touch-file"); int ret = runAndBlock("touch", touchFile.getAbsolutePath()); assertEquals(0, ret); FileStatus fileStatus = FileContext.getLocalFSFileContext().getFileStatus( new Path(touchFile.getAbsolutePath())); assertEquals(expectedRunAsUser, fileStatus.getOwner()); cleanupAppFiles(expectedRunAsUser); conf.unset(YarnConfiguration.NM_NONSECURE_MODE_LIMIT_USERS); exec.setConf(conf); }