### Question:
ProtoLiteUtils { @ExperimentalApi("https: public static void setExtensionRegistry(ExtensionRegistryLite newRegistry) { globalRegistry = checkNotNull(newRegistry, "newRegistry"); } private  ProtoLiteUtils(); @ExperimentalApi("https://github.com/grpc/grpc-java/issues/1787") static void setExtensionRegistry(ExtensionRegistryLite newRegistry); static Marshaller<T> marshaller(T defaultInstance); static Metadata.BinaryMarshaller<T> metadataMarshaller(
      T defaultInstance);  }### Answer:
@Test public void extensionRegistry_notNull() { thrown.expect(NullPointerException.class); thrown.expectMessage("newRegistry"); ProtoLiteUtils.setExtensionRegistry(null); }