question: private CoderResult controlSequence ( short newByte ) { if ( newByte >= 0x30 && newByte <= 0x3F ) { if ( state == CONTROL_SEQUENCE_IF ) { return malformedInput ( ERR_CTRLPI ) ; } queue . write ( newByte ) ; } else if ( newByte >= 0x20 && newByte <= 0x2F ) { state = CONTROL_SEQUENCE_IF ; queue . write ( newByte ) ; } else if ( newByte >= 0x40 && newByte <= 0x7E ) { state = NORMAL_BYTES ; queue . reset ( ) ; } else { return malformedInput ( ERR_CTRLBYTE ) ; } return CoderResult . UNDERFLOW ; }
target:  Parses directionality, as well as unknown, but valid, control sequences.