question: private static final void encodeQuotedPrintable ( int b , ByteArrayOutputStream buffer ) { buffer . write ( ESCAPE_CHAR ) ; char hex1 = Character . toUpperCase ( Character . forDigit ( ( b > > 4 ) & 0xF , 16 ) ) ; char hex2 = Character . toUpperCase ( Character . forDigit ( b & 0xF , 16 ) ) ; buffer . write ( hex1 ) ; buffer . write ( hex2 ) ; }
target:  Encodes byte into its quoted-printable representation.