1    package arraylistplay;
2    
3    
4    import java.util.ArrayList;
5    
6    public class Primes {
7    
8        public static void main(String[] args) {
9    
10           ArrayList<Integer> primes = new ArrayList<>();
11   
12           primes.add(2);
13           primes.add(3);
14           primes.add(5);
15           primes.add(7);
16   
17           System.out.println("size of primes list = " + primes.size() );
18           System.out.println("first prime = " + primes.get(0));
19           System.out.println("last prime = " + primes.get(3));
20           System.out.println("last prime = " + primes.get(primes.size()-1));
21   
22           System.out.println("\nThe initial list ...");
23           for (Integer prime : primes) {
24               System.out.println(prime);
25           }
26   
27           int temp = primes.get(0);
28           primes.set(0, primes.get(primes.size()-1));
29           primes.set(primes.size()-1, temp);
30   
31           System.out.println("\nThe final list ...");
32           for ( Integer prime : primes ){
33               System.out.println(prime);
34           }
35       }
36   }
37   
38