code: int write(final ByteBuf buffer, int offset, int length) {
          int index = buffer.forEachByte(offset, length, writeProcessor);
          return index == -1 ? length : index - offset;
      }
docs: Writes an array to the block.
  @param buffer The buffer to write
  @param offset The offset within the input data to write from
  @param length The number of bytes of input data to write
  @return The actual number of input bytes written. May be less than the number requested, or
  zero if the block is already full