Java.util.ArrayList.add() Method in Java

Below are the add() methods of ArrayList in Java:

1. boolean add(Object o) : This method appends the specified element to the end of this list.

   Parameters:    
   object o: The element to be appended to this list.
   Exception: NA

   // Java code to illustrate add(Object o)
   import java.io.*;
   import java.util.ArrayList;
   
   public class ArrayListDemo {
   public static void main(String[] args)
       {
   
           // create an empty array list with an initial capacity
           ArrayList<Integer> arrlist = new ArrayList<Integer>(5);
   
           // use add() method to add elements in the list
           arrlist.add(15);
           arrlist.add(20);
           arrlist.add(25);
   
           // prints all the elements available in list
           for (Integer number : arrlist) {
               System.out.println("Number = " + number);
           }
       }
   }

   Output:

   Number = 15
   Number = 20
   Number = 25
   

2. void add(int index, Object element) : This method inserts the specified element E at the specified position in this list.It shifts the element currently at that position (if any) and any subsequent elements to the right (will add one to their indices).

   Parameters:
   index : The index at which the specified element is to be inserted.
   element : The element to be inserted.
   
   Exception:
   Throws IndexOutOfBoundsException if the specified
   index is out of range (index  size()).

   // Java code to illustrate
   // void add(int index, Object element)
   import java.io.*;
   import java.util.ArrayList;
   
   public class ArrayListDemo {
   public static void main(String[] args)
       {
   
           // create an empty array list with an initial capacity
           ArrayList<Integer> arrlist = new ArrayList<Integer>(5);
   
           // use add() method to add elements in the list
           arrlist.add(10);
           arrlist.add(22);
           arrlist.add(30);
           arrlist.add(40);
   
           // adding element 35 at fourth position
           arrlist.add(3, 35);
   
           // let us print all the elements available in list
           for (Integer number : arrlist) {
               System.out.println("Number = " + number);
           }
       }
   }

   Output:

   Number = 10
   Number = 22
   Number = 30
   Number = 35
   Number = 40
   

This article is contributed by Shambhavi Singh. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.