public static int nextClearBit(long v,int start){
  if (start >= Long.SIZE) {
    return -1;
  }
  long cur=~v & (LONG_ALL_BITS << start);
  if (cur == 0) {
    return -1;
  }
  return Long.numberOfTrailingZeros(cur);
}

public static int nextClearBit ( long v , int start ) { if ( start >= Long . SIZE ) { return - 1 ; } long cur = ~ v & ( LONG_ALL_BITS << start ) ; if ( cur == 0 ) { return - 1 ; } return Long . numberOfTrailingZeros ( cur ) ; }
find the next clear bit .
