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;
}

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 ; }
create a internet mask .
