Through the ListIterator, we can iterate the list in forward and backward directions. Java provides an interface Iterator to iterate over the Collections, such as List, Map, etc. An Iterator is an object that can be used to loop through collections, like ArrayList and HashSet. https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/ListIterator.html, Mathematical Operations on Algebraic Expressions - Algebraic Expressions and Identities | Class 8 Maths, OYO Rooms Interview Experience (Virtual 2021), Difference between == and .equals() method in Java, Difference between Abstract Class and Interface in Java, Different ways of Reading a text file in Java, Write Interview The idea here is to convert the iterator to an iterable which can be easily done by using lamdba in Java 8 and above. . Java Iterator. 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() . The Iterator interface has the following major characteristics: The Iterator interface is available from the Java 1.2 collection framework onwards. Some of the important methods declared by the Iterator interface are hasNext () … Hierarchy of ListIterator. The Iterator interface of the Java collections framework allows us to access elements of a collection. default void forEachRemaining​(Consumer countriesIterator = countries.iterator(); while(countriesIterator.hasNext()) { System.out.println(countriesIterator.next()); } The hasNext() method checks if there are any elements remaining in the list. It contains two key methods next () and hasNaxt () that allows us to perform an iteration over the List. There is no current element in ListIterator. It is available since Java 8. List Iterator in Java: ListIterator is the child interface of Iterator. It performs the specified action for each element until all elements have been processed or the action throws an exception. The enhanced for loop:. It supports Bi-directional traversing i.e both forward and backward direction iteration. Throughout this section, we will use ArrayList. Performs the given action for each remaining element until all elements have been processed or the action throws an exception. It is called an "iterator" because "iterating" is the technical term for looping. It is compact, easy, and readable. If a generic list is being accessed, the iterator will return something of the list’s type. 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. The Iterable interface provides forEach() method to iterate over the List. ArrayList listIterator () method. 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