### Question:
ListDeserializer { public static <E extends DataObject> List<E> deserializeHeaders(short version, int length, ByteBuf input, CodeKeyMaker keyMaker, DeserializerRegistry registry) { List<E> items = null; if (input.readableBytes() > 0) { items = new ArrayList<>(); int startIndex = input.readerIndex(); boolean exceptionLogged = false; while ((input.readerIndex() - startIndex) < length){ HeaderDeserializer<E> deserializer; MessageCodeKey key = keyMaker.make(input); try { deserializer = registry.getDeserializer(key); } catch (ClassCastException | IllegalStateException e) { if (!exceptionLogged) { LOG.warn("Problem during reading table feature property. Skipping unknown feature property: {}." + "If more information is needed, set org.opendaylight.openflowjava do DEBUG log level.", key, e.getMessage()); if (LOG.isDebugEnabled()) { LOG.debug("Detailed exception: {}", e); LOG.debug("This exception is logged only once for each multipart reply (table features) to " + "prevent log flooding. There might be more of table features related exceptions."); } exceptionLogged = true; } input.skipBytes(2 * EncodeConstants.SIZE_OF_SHORT_IN_BYTES); continue; } E item = deserializer.deserializeHeader(input); items.add(item); } } return items; } private  ListDeserializer(); static List<E> deserializeList(short version, int length,
            ByteBuf input, CodeKeyMaker keyMaker, DeserializerRegistry registry); static List<E> deserializeHeaders(short version, int length,
            ByteBuf input, CodeKeyMaker keyMaker, DeserializerRegistry registry);  }### Answer:
@Test public void test2() { ByteBuf buffer = PooledByteBufAllocator.DEFAULT.buffer(); List<DataObject> list = ListDeserializer.deserializeHeaders(EncodeConstants.OF13_VERSION_ID, 42, buffer, keyMaker, registry); Assert.assertNull("List is not null", list); }