### Question:
OSUtils { public static String getGroup() throws IOException { if (isWindows()) { String currentProcUserName = System.getProperty("user.name"); String result = exeCmd(String.format("net user \"%s\"", currentProcUserName)); String line = result.split("\n")[22]; String group = PATTERN.split(line)[1]; if (group.charAt(0) == '*') { return group.substring(1); } else { return group; } } else { String result = exeCmd("groups"); if (StringUtils.isNotEmpty(result)) { String[] groupInfo = result.split(" "); return groupInfo[0]; } } return null; } private  OSUtils(); static double memoryUsage(); static double availablePhysicalMemorySize(); static double totalMemorySize(); static double loadAverage(); static double cpuUsage(); static List<String> getUserList(); static boolean createUser(String userName); static String getGroup(); static String exeCmd(String command); static String exeShell(String[] command); static int getProcessID(); static boolean isMacOS(); static boolean isWindows(); static String getOSName(); static Boolean checkResource(double systemCpuLoad, double systemReservedMemory); static Boolean checkResource(Configuration conf, Boolean isMaster); static final ThreadLocal<Logger> taskLoggerThreadLocal; static final String TWO_DECIMAL; static final double NEGATIVE_ONE; }### Answer:
@Test public void getGroup() { try { String group = OSUtils.getGroup(); Assert.assertNotNull(group); } catch (IOException e) { Assert.fail("get group failed " + e.getMessage()); } }