1    package arraylistplay;
2    
3    import java.util.ArrayList;
4    
5    public class Primes {
6        public static void main(String[] args) {
7            ArrayList<Integer> primes = new ArrayList<>();
8    
9            primes.add(2);
10           primes.add(3);
11           primes.add(5);
12           primes.add(7);
13   
14           System.out.println("size of primes list = " + primes.size());
15           System.out.println("first prime = " + primes.get(0));
16           System.out.println("last prime = " + primes.get(3));
17           System.out.println("last prime = " + primes.get(primes.size()-1));
18   
19           System.out.println("\nThe initial list ...");
20           for ( Integer prime : primes ) {
21               System.out.println(prime);
22           }
23           int temp = primes.get(0);
24           primes.set(0, primes.get(primes.size()-1));
25           primes.set(primes.size()-1,temp);
26   
27           System.out.println("\nThe final list ...");
28           for ( Integer prime : primes ) {
29               System.out.println(prime);
30           }
31       }
32   }
33