code: private byte[] getFlagBytes()
  	{
  		byte flags[] = new byte[2];
  
  		if (tagAlterDiscard) flags[0] |= 0x40;
  		if (fileAlterDiscard) flags[0] |= 0x20;
  		if (readOnly) flags[0] |= 0x10;
  		if (grouped) flags[1] |= 0x40;
  		if (compressed) flags[1] |= 0x08;
  		if (encrypted) flags[1] |= 0x04;
  		if (unsynchronised) flags[1] |= 0x02;
  		if (lengthIndicator) flags[1] |= 0x01;
  
  		return flags;
  	}
docs: A helper function for the getFrameBytes method that processes the info
  in the frame and returns the 2 byte array of flags to be added to the
  header.
  
  @return a value of type 'byte[]'