question: public InetNetwork ( InetAddress inetAddress , int subnetBits ) { _inetAddress = inetAddress ; _address = inetAddress . getAddress ( ) ; if ( subnetBits < 0 ) subnetBits = 8 * _address . length ; _subnetBits = subnetBits ; _subnetByte = subnetBits / 8 ; _subnetMask = ~ ( ( 1 << ( 8 - subnetBits % 8 ) ) - 1 ) & 0xff ; }
target:  Create a internet mask.