The get() method of ArrayList in Java is used to get the element of a specified index within the list.
Syntax:
get(index)
Parameter: Index of the elements to be returned. It is of data-type int.
Return Type: The element at the specified index in the given list.
Exception: It throws IndexOutOfBoundsException if the index is out of range (index=size())
Note: Time Complexity: ArrayList is one of the List implementations built a top an array. Hence, get(index) is always a constant time O(1) operation.
Example:
Java
// Java Program to Demonstrate the working of // get() method in ArrayList // Importing ArrayList class import java.util.ArrayList; // Main class public class GFG { // Main driver method public static void main(String[] args) { // Creating an Empty Integer ArrayList ArrayList<Integer> arr = new ArrayList<Integer>( 4 ); // Using add() to initialize values // [10, 20, 30, 40] arr.add( 10 ); arr.add( 20 ); arr.add( 30 ); arr.add( 40 ); // Printing elements of list System.out.println( "List: " + arr); // Getting element at index 2 int element = arr.get( 2 ); // Displaying element at specified index // on console inside list System.out.println( "the element at index 2 is " + element); } } |
List: [10, 20, 30, 40] the element at index 2 is 30
Example 2: Program to demonstrate the error
Java
// Java Program to Demonstrate Error Generated // while using get() method in ArrayList // Importing ArrayList class import java.util.ArrayList; // Main class public class GFG { // Main driver method public static void main(String[] args) { // Creating an Empty Integer ArrayList ArrayList<Integer> arr = new ArrayList<Integer>( 4 ); // Using add() method to insert elements // and adding custom values arr.add( 10 ); arr.add( 20 ); arr.add( 30 ); arr.add( 40 ); // Getting element at index 2 int element = arr.get( 5 ); // Print all the elements of ArrayList System.out.println( "the element at index 2 is " + element); } } |
Output :
Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 5, Size: 4 at java.util.ArrayList.rangeCheck(ArrayList.java:657) at java.util.ArrayList.get(ArrayList.java:433) at GFG.main(GFG.java:22)