1. flip

    public void flip(int fromIndex,
                 int toIndex)

   -- as per document ----
   Returns:
      the index of the next set bit.
 --correction ----
  this method returns void

2. public void clear(int fromIndex,
                  int toIndex)

   Sets the bits from the specified fromIndex(inclusive) to the specified
   toIndex(exclusive) to false.
   Parameters:
      fromIndex - index of the first bit to be set.
      toIndex - index after the last bit to be set.
  --correction-----
  Parameters:
      fromIndex - index of the first bit to be cleared.
      toIndex - index after the last bit to be cleared.