What is the difference between Iterator and ListIterator?

1.	What is the difference between Iterator and ListIterator?
Answer» We can traverse the elements in a LIST using Iterator in a forward direction. Using LISTITERATOR, we can traverse the elements in the forward and backward direction both. Iterator can be USED in these collection types: List, Set, and Queue. ListIterator can be used in List collection only. Iterator has the following FUNCTIONALITIES: boolean hasNext() E next() void remove() ListIterator has the following functionalities: void add (E e) boolean hasNext() boolean hasPrevious() void remove() Iterator can only perform remove operation while traversing the elements in a collection. If we TRY to add elements, it will throw ConcurrentModificationException. ListIterator can perform add, remove operation while traversing the elements in a collection. We won’t get any exception while adding element using ListIterator.

Answer»

We can traverse the elements in a LIST using Iterator in a forward direction. Using LISTITERATOR, we can traverse the elements in the forward and backward direction both. Iterator can be USED in these collection types: List, Set, and Queue.

ListIterator can be used in List collection only.

Iterator has the following FUNCTIONALITIES:

boolean hasNext()
E next()
void remove()

ListIterator has the following functionalities:

void add (E e)
boolean hasNext()
boolean hasPrevious()
void remove()

Iterator can only perform remove operation while traversing the elements in a collection. If we TRY to add elements, it will throw ConcurrentModificationException.

ListIterator can perform add, remove operation while traversing the elements in a collection. We won’t get any exception while adding element using ListIterator.

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