code: public static ByteBuf writeAscii(ByteBufAllocator alloc, CharSequence seq) {
          // ASCII uses 1 byte per char
          ByteBuf buf = alloc.buffer(seq.length());
          writeAscii(buf, seq);
          return buf;
      }
docs: Encode a {@link CharSequence} in <a href="http://en.wikipedia.org/wiki/ASCII">ASCII</a> and write
  it to a {@link ByteBuf} allocated with {@code alloc}.
  @param alloc The allocator used to allocate a new {@link ByteBuf}.
  @param seq The characters to write into a buffer.
  @return The {@link ByteBuf} which contains the <a href="http://en.wikipedia.org/wiki/ASCII">ASCII</a> encoded
  result.