, CTO at SjArc Studios, 6 years of java experience Answered September 21, 2014 Iterate over the hashmap, and then inside that foreach loop, iterate over the arraylist. ArrayList Features. To iterate over elements of ArrayList, you can use Java loop statements like Java while loop, Java For Loop or ArrayList forEach. This method traverses each element of the Iterable of ArrayList until all elements have been Processed by the method or an exception is raised. How to iterate ArrayList using ListIterator? Some of the important methods declared by the Iterator interface are hasNext() and next(). – Java ArrayList permits all elements, including null. There are 7 ways you can iterate through List. #1 normal for loop Text 1 Text 2 Text 3 #2 advance for loop Text 1 Text 2 Text 3 #3 while loop Text 1 Text 2 Text 3 #4 iterator Text 1 Text 2 Text 3 Tags : arraylist java loop Related Articles Iterating, traversing or Looping ArrayList in Java means accessing every object stored in ArrayList and performing some operations like printing them. Java Loop Arraylist Example ryan 2019-10-06T15:12:44+00:00 On this section we will be showing some java examples on how to iterate or loop through an arraylist. The Java Iterator is a reference over a collection object. It is not recommended to use ArrayList.remove () when iterating over elements. Syntax: Parameter: No parameters. + When adding new elements, Java ArrayList grows its size automatically. A program that demonstrates iteration through ArrayList using the Iterator interface is given as follows, The output of the above program is as follows, The ArrayList aList is created. The example also shows how to iterate ArrayList in backward direction using ListIterator. Most of the programs are using ArrayList over Array Because of ArrayList’s Functionality and flexibility over Array. We can print Java ArrayList object’s items using a loop. Totally different thing. next() : returns the next element from the Iterator. ArrayList: [Java, JavaScript, Python] Iterating over ArrayList using for loop: Java, JavaScript, Python, In the above example, we have created an arraylist named languages . A Computer Science portal for geeks. If you want to iterate ArrayList in reverse order, you can use for loop and start with the end index (i.e. 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. 1- Using forEach. advanced for loop, traditional for loop with size(), By using Iterator and ListIterator along with while loop etc. Java program to iterate through an arraylist of objects using … Looks like you should use an array of ArrayLists. 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 A program that demonstrates this is given as followsExample Live Demoimport java. How to iterate through Java List? The operation is performed in the order of iteration if that order is specified by the method. By default, actions are performed on elements taken in the order of iteration. forEach() is added as part of java 8 changes. A 'for' loop to iterate over an enum in Java Difference between HashMap, LinkedHashMap and TreeMap Convert ArrayList to String[] array As shown below, method simply iterate over all list elements and call action.accept() for each element. Java ArrayList Iterator() method. This may lead to ConcurrentModificationException (Refer this for a sample program with this exception). In this tutorial, we will go through each of these looping techniques to iterate over elements of ArrayList. Introduction to Java Iterator. Iterate from starting to middle of the ArrayList, and swap the element with the element on the other side of the ArrayList. Using For-Each loop (Advanced for loop), available from Java 5; Using Iterator or ListIterator (Use ListIterator only if you want to iterate both forward and backward rather than looping an ArrayList sequentially). ArrayList forEach() method. In JavaScript, you are using an Array. Iterate through ArrayList with for loop. That’s the only way we can improve. 1. There are different ways to iterate List in Java, traversal of Java List or ArrayList, Vector, LinkedList object to get its values.