Check out example codes for "how to add to an arraylist java". It will help you in understanding the concepts better.

Code Example 1

import java.util.ArrayList;
public class Details {
    public static void main(String[] args) {

        //ArrayList<String> Declaration
        ArrayList<String> al= new ArrayList<String>();
        //add method for String ArrayList
        al.add("Ram");
        al.add("Shyam");
        al.add("CPS");
        al.add("John");
        al.add("Steve");
        System.out.println("Elements of ArrayList of String Type: "+al);

Code Example 2

// 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); 
        } 
    } 
}

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