### Question:
HddsUtils { public static void validatePath(Path path, Path ancestor) { Preconditions.checkNotNull(path, "Path should not be null"); Preconditions.checkNotNull(ancestor, "Ancestor should not be null"); Preconditions.checkArgument( path.normalize().startsWith(ancestor.normalize()), "Path should be a descendant of %s", ancestor); } private  HddsUtils(); static InetSocketAddress getScmAddressForClients(
      ConfigurationSource conf); static InetSocketAddress getScmAddressForBlockClients(
      ConfigurationSource conf); static Optional<String> getHostNameFromConfigKeys(
      ConfigurationSource conf,
      String... keys); static Optional<String> getHostName(String value); static OptionalInt getHostPort(String value); static OptionalInt getPortNumberFromConfigKeys(
      ConfigurationSource conf, String... keys); static Collection<InetSocketAddress> getSCMAddresses(
      ConfigurationSource conf); static InetSocketAddress getReconAddresses(
      ConfigurationSource conf); static InetSocketAddress getSingleSCMAddress(
      ConfigurationSource conf); static String getHostName(ConfigurationSource conf); static boolean isReadOnly(
      ContainerProtos.ContainerCommandRequestProto proto); static boolean requireBlockToken(
      ContainerProtos.Type cmdType); static BlockID getBlockID(ContainerCommandRequestProto msg); static ObjectName registerWithJmxProperties(
      String serviceName, String mBeanName, Map<String, String> jmxProperties,
      Object mBean); static long getTime(); static void validatePath(Path path, Path ancestor); static final String OZONE_SCM_SERVICE_ID; static final String OZONE_SCM_SERVICE_INSTANCE_ID; }### Answer:
@Test public void validatePath() throws Exception { HddsUtils.validatePath(Paths.get("/"), Paths.get("/")); HddsUtils.validatePath(Paths.get("/a"), Paths.get("/")); HddsUtils.validatePath(Paths.get("/a"), Paths.get("/a")); HddsUtils.validatePath(Paths.get("/a/b"), Paths.get("/a")); HddsUtils.validatePath(Paths.get("/a/b/c"), Paths.get("/a")); HddsUtils.validatePath(Paths.get("/a/../a/b"), Paths.get("/a")); LambdaTestUtils.intercept(IllegalArgumentException.class, () -> HddsUtils.validatePath(Paths.get("/b/c"), Paths.get("/a"))); LambdaTestUtils.intercept(IllegalArgumentException.class, () -> HddsUtils.validatePath(Paths.get("/"), Paths.get("/a"))); LambdaTestUtils.intercept(IllegalArgumentException.class, () -> HddsUtils.validatePath(Paths.get("/a/.."), Paths.get("/a"))); LambdaTestUtils.intercept(IllegalArgumentException.class, () -> HddsUtils.validatePath(Paths.get("/a/../b"), Paths.get("/a"))); }