Iterator vs. ListIterator in Java: Which statements are correct about their capabilities and APIs?

Introduction / Context: Java provides Iterator for one-way traversal and ListIterator for bidirectional traversal and in-place modification of lists. This question checks which capabilities belong to which interface.

Given Data / Assumptions:

• Statements include: the methods of Iterator, inheritance relationships, and features of ListIterator.

Concept / Approach: Iterator declares exactly three methods: hasNext(), next(), and remove(). ListIterator extends Iterator (not List) and adds backward traversal (hasPrevious(), previous()), modification methods (add(), set(), and remove() inherited), and positional queries (nextIndex(), previousIndex()).

Step-by-Step Solution:

Verification / Alternative check: The Javadoc for java.util.ListIterator lists these additional methods explicitly and shows it extends Iterator.

Why Other Options Are Wrong:

• Options containing 2 are incorrect because ListIterator does not extend List.

Common Pitfalls: Confusing List (a collection type) with ListIterator (an iterator over lists), and forgetting the backward traversal capability.

Final Answer: 1, 3, 4 and 5