An Iterator is an object that can be used to loop through collections, like ArrayList and HashSet.It is called an "iterator" because "iterating" is the technical term for looping. Ways to iterate over a list in Java. Learn more . We can use iterator() that returns an iterator to iterate over a set as shown Java Iterator. This was the default approach in Java 1.4 and older versions. 1.

Iterator interface in Java is a member of the Java Collection Framework. In Java, iteration over Map can be done in various ways. Remember that we cannot iterate over map directly using iterators, because Map interface is not the part of Collection.All maps in Java implements Map interface. Before we begin, we encourage you to read below post that points out a bug in Stack class that causes stack elements to be printed in FIFO order instead of expected LILO order. Iterator takes the place of Enumeration in the Java Collections Framework. In this tutorial, we will learn what is iterator, how to use it and what are the issues that can come up while using it. Java Iterator tutorial with examples will help you to understand how to use the Java Iterator in an easy way. This method uses java.util.Iterator to go through the HashMap. Iteration is one of the basic operations carried on a collection. Iterator vs Foreach In Java Retrieving Elements from Collection in Java (For-each, Iterator, ListIterator and EnumerationIterator) This article is contributed by Gaurav Miglani. Basically, an iteration takes elements from a collection one after another, from the first element to the last one. Iterate through HashMap using Iterator. To use an Iterator, you must import it from the java.util package. Viewed 912k times 576. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. Java Iterator with examples. Details Written by Nam Ha Minh Last Updated on 15 June 2019 | Print Email. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. Iterator is used for iterating (looping) various collection classes such as HashMap, ArrayList, LinkedList etc. Java Iterator is used to iterate over a collection to retrieve its elements. Although the following example uses Generics, so you need Java 1.5 + to execute it In this post, we will discuss various methods to iterate over Set in Java.

This interface is a member of the Java Collections Framework. By Chaitanya Singh | Filed Under: Java Collections. 199.

The 4 Methods for Iterating Collections in Java. Method names have been improved. Active 4 months ago. Iterators differ from enumerations in two ways: Iterators allow the caller to remove elements from the underlying collection during the iteration with well-defined semantics. Ask Question Asked 6 years, 10 months ago. How to iterate Map in Java.

There are following types of maps in Java: In this post, we will discuss various methods to iterate through Stack in Java.