public static byte [ ] hexToBytes ( String s ) { try { if ( s == null ) return new byte [ 0 ] ; s = s . toUpperCase ( ) ; int len = s . length ( ) ; byte [ ] data = new byte [ len / 2 ] ; for ( int i = 0 ; i < len ; i += 2 ) { data [ i / 2 ] = ( byte ) ( ( Character . digit ( s . charAt ( i ) , 16 ) << 4 ) + Character . digit ( s . charAt ( i + 1 ) , 16 ) ) ; } return data ; } catch ( StringIndexOutOfBoundsException e ) { return null ; } }
Convert a hexadecimal string to a byte array .