Different Ways to iterate List in Java. Converting the iterator to an iterable. It can be ArrayList, LinkedList anything which implements the basic Collection Interface.With the iterator we can get all the items in the collection one by one. The collection API implements the iterator() method and hence data can be retrieved from interfaces like Map, List, Queue, Deque and Set which are all implemented from the collection framework. Introduction to Iterator in Java. The Java iterate through ArrayList programs. If the remove() method is not preceded by the next() method, then the exception IllegalStateException is thrown. Learn how to retrieve values from ArrayList in Java using for loop, while loop, iterator and stream api.. An element can be removed from a Collection using the Iterator method remove(). util package. Let’s first create a List object and add some elements to it. ` I want to ask how I can "reset" my iterator to first element. The iterator() method of ArrayList class in Java Collection Framework is used to get an iterator over the elements in this list in proper sequence. Using this interface you can iterate through any Java collections and process the collection elements. Summary. Introduction to Java Iterator. 1. Answer: The listIterator method belongs to java.util. This method removes the current element in the Collection. 3. Q #3) What is the use of the listIterator method in Java? The iterator interface is present in Java since version 1.2. Then we convert the iterable to Stream by using StreamSupport.stream() method. The tutorial has shown us how to iterate over a List or Set in Java 8.We can see that forEachRemaining and forEach are new APIs introduced in Java 8, can be used to iterate over collections like Set, List, etc. Syntax: Iterator iterator() Parameter: This method do not accept any parameter. Using JDK 5 for-each Loop; Simple For loop; Using Iterator; Using While Loop; Using JDK 8 forEach with stream() 2. overview of ways of iterate List in Java I know that I can get list iterator of the first element in this way: iter= list.listIterator(1); The returned iterator is fail-fast. Finally, we get a List from the Stream using a Collector. This method should return the Iterator object for Singly Linked List. LinkedList list; Iterator iter=list.listIterator; iter.next(); iter.next(); Over and over again and after many moves of the iterator I need to "reset" the position of iterator. Iterate through List Java example shows how to iterate over a List using for loop, enhanced for loop, Iterator, ListIterator, while loop and Java 8 forEach. There are five ways to loop ArrayList.. For Loop; Advanced for loop; List Iterator; While Loop; Java 8 Stream; 1. * package. We can iterate … Iterate through ArrayList with for loop To provide the Iterator object, we need to implement the java.util.Iterator to Singly Linked List class. 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. After implementing Iterator, we need to override the two methods, public boolean hasNext() and public T next(). 1. 2. How to iterate through List in Java? #1 iterator Array 1 Array 2 Array 3 #2 for Array 1 Array 2 Array 3 #3 for advance Array 1 Array 2 Array 3 #4 while Array 1 Array 2 Array 3 Tags : iterate java list loop Related Articles The idea here is to convert the iterator to an iterable which can be easily done by using lamdba in Java 8 and above. An Iterator is an interface that is used to fetch elements one by one in a collection. It is available in Java package called Java. 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