### Question:
OF10HelloInputMessageFactory implements OFSerializer<HelloInput> { @Override public void serialize(HelloInput message, ByteBuf outBuffer) { ByteBufUtils.writeOFHeader(MESSAGE_TYPE, message, outBuffer, EncodeConstants.OFHEADER_SIZE); }  @Override void serialize(HelloInput message, ByteBuf outBuffer);  }### Answer:
@Test public void testWithoutElementsSet() throws Exception { HelloInputBuilder hib = new HelloInputBuilder(); BufferHelper.setupHeader(hib, EncodeConstants.OF10_VERSION_ID); HelloInput hi = hib.build(); ByteBuf out = UnpooledByteBufAllocator.DEFAULT.buffer(); helloFactory.serialize(hi, out); BufferHelper.checkHeaderV10(out, (byte) 0, 8); }