Get the current value in the sequence (the one returned by the
most recent call on next()). This will be null before the first
call of next(). This method does not change the state of the iterator.
the current item, the one most recently returned by a call on
next(). Returns null if next() has not been called, or if the end
of the sequence has been reached.
Get the current position. This will usually be zero before the first call
on next(), otherwise it will be the number of times that next() has
been called. Once next() has returned null, the preferred action is
for subsequent calls on position() to return -1, but not all existing
implementations follow this practice. (In particular, the EmptyIterator
is stateless, and always returns 0 as the value of position(), whether
or not next() has been called.)
This method does not change the state of the iterator.
the current position, the position of the item returned by the
most recent call of next(). This is 1 after next() has been successfully
called once, 2 after it has been called twice, and so on. If next() has
never been called, the method returns zero. If the end of the sequence
has been reached, the value returned will always be <= 0; the preferred
value is -1.