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