Collections:

ARRAYLIST - INTRODUCTION

Sample Input and Output 1:

Enter the username 1
John
Do you want to continue?(y/n)
y
Enter the username 2
Joe
Do you want to continue?(y/n)
n
The Names entered are:
John
Joe

CODE:

import java.util.ArrayList;

import java.util.Scanner;

public class Main {

    public static void main(String args[]) {

String user;

Scanner sc = new Scanner(System.in);

ArrayList<String> al = new ArrayList<String>();

int i = 1;

do {

System.out.println("Enter the username "+i);

al.add(sc.nextLine());

System.out.println("Do you want to continue?(y/n)");

user = sc.nextLine();

i++;

}while(user.equalsIgnoreCase("y"));

System.out.println("The Names entered are:");

for(String a:al) {

System.out.println(a);

}

}

}