Returns true if the iteration has more elements.

  Returns true if the iteration has more elements. (In other
words, returns true if next would return an element
rather than throwing an exception.)
Returns: true if the iterator has more elements.

  Returns the next element in the iteration.

  Returns the next element in the iteration.
Returns: the next element in the iteration.
Throws:
- NoSuchElementException - iteration has no more elements.

  Removes from the underlying collection the last element returned by the iterator (optional operation).

  Removes from the underlying collection the last element returned by the
iterator (optional operation). This method can be called only once per
call to next. The behavior of an iterator is unspecified if
the underlying collection is modified while the iteration is in
progress in any way other than by calling this method.
Throws:
- UnsupportedOperationException - if the remove operation is not supported by this Iterator.
- IllegalStateException - if the next method has not yet been called, or the remove method has already been called after the last call to the next method.