ArrayList get(index) Method in Java with Examples

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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);
    }
}

Output

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)