@Override
      public int capacity(final ByteBuffer source,
                          final int offset) {
        final byte headerByte0 = source.get(offset);
        final int headerBytes1_4 = source.getInt(offset + 1);
        return capacity(headerByte0, headerBytes1_4);
      }
@Override
      public int capacity(final ByteBuffer source,
                          final int offset)