1    package arraylistplay;
2    
3    import java.util.ArrayList;
4    
5    public class Primes {
6        public static void main(String[] args ){
7    
8            ArrayList<Integer> primes = new ArrayList<>();
9    
10           primes.add(2);
11           primes.add(3);
12           primes.add(5);
13           primes.add(7);
14   
15   
16           System.out.println("size of primes list = "  +primes.size());
17           System.out.println("first prime = " +primes.get(0));
18           System.out.println("last prime = " +primes.get(3));
19           System.out.println("last prime = " +primes.get(primes.size()-1));
20   
21           System.out.println("\nThe initial list...");
22           for(Integer prime : primes){
23               System.out.println(prime);
24           }
25   
26           int temp = primes.get(0);
27           primes.set(0, primes.get(primes.size()-1));
28           primes.set(primes.size()-1, temp);
29   
30           System.out.println("\nThe final list...");
31           for(Integer prime : primes){
32               System.out.println(prime);
33           }
34       }
35   }
36