![]() Iterator returned by ArrayList is a fail-fast. Moving cursor to next element using reference variable itr. Checking the next element availability using reference variable itr. At the beginning, itr(cursor) will point to index just before the first element in al. Create an object of Iterator by calling iterator() method using reference variable al. (al) // It will print all elements at a time. Creating an ArrayList object of type String. We will also remove the last element returned by the iterator. Let’s write a Java program in which we will iterate elements of ArrayList by using iterator. This method must be called after calling next() method otherwise, it will throw “IllegalStateException”.įor more detail with diagram, go to this tutorial: Iterator in Java ![]() remove(): The remove() method removes the last element returned by the iterator. If the iteration has no more elements then it will throw “NoSuchElementException”.ģ. next(): It returns the next element in the iteration. hasNext(): This method returns true if the iteration has more elements in the forward direction.Ģ. The Iterator interface defines three methods. It is useful when we want to remove the last element during iteration. The iterator() method is used to iterate over elements of ArrayList in Java. ![]() ("Iteration using while loop") Ģ0 25 null 30 25 How to iterate ArrayList in Java using Iterator Iteration of ArrayList using while loop. Create an object of ArrayList of type Integer. That means that we can not add or remove an element in the ArrayList during Iteration otherwise, it will throw ConcurrentModificationException. Iteration over elements in the ArrayList using Enhanced for loop is fail-fast. Iterating ArrayList using Enhance for loop. Call get() method to return elements on specified index after iterating.Īl.set(2, "G") // It will replace current element at position 2 with element G.Īl.set(3, null) // adding null element at position 3. Therefore, we will store it using variable elementsize of type int. Since the return type of size method is an integer. Iterating ArrayList using for loop and call size() method to get the size of elements. (al) // It will display all elements of ArrayList at a time. Displaying original elements of the ArrayList. Call add() method to add the elements in the list using reference variable al.Īl.add("A") // Adding element at index 0.Īl.add("B") // Adding element at index 1.Īl.add("C") // Adding element at index 2.Īl.add("D") // Adding element at index 3.Īl.add("E") // Adding element at index 4. In the list, we can add only String type of elements. Create object of ArrayList of type String. Let’s take an example program where we will implement the concepts of simple for loop and enhanced for loop to understand better.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |