ListIterator

Posted 2020-09-17 wqkant

public interface ListIterator<E>
extends Iterator<E>

An iterator for lists that allows the programmer to traverse the list in either direction, modify the list during iteration, and obtain the iterator‘s current position in the list. A ListIterator has no current element; its cursor position always lies between the element that would be returned by a call to previous() and the element that would be returned by a call to next(). An iterator for a list of length n has n+1 possible cursor positions, as illustrated by the carets (^) below:

                      Element(0)   Element(1)   Element(2)   ... Element(n-1)
 cursor positions:  ^            ^            ^            ^                  ^
 

Note that the remove() and set(Object) methods are not defined in terms of the cursor position; they are defined to operate on the last element returned by a call to next() or previous().

 

 

void	add(E e) Inserts the specified element into the list (optional operation).
boolean	hasNext() Returns true if this list iterator has more elements when traversing the list in the forward direction.
boolean	hasPrevious() Returns true if this list iterator has more elements when traversing the list in the reverse direction.
E	next() Returns the next element in the list and advances the cursor position.
int	nextIndex() Returns the index of the element that would be returned by a subsequent call to next().
E	previous() Returns the previous element in the list and moves the cursor position backwards.
int	previousIndex() Returns the index of the element that would be returned by a subsequent call to previous().
void	remove() Removes from the list the last element that was returned by next() or previous() (optional operation).
void	set(E e)