1    /* 
2     *  enter code from the lab to learn how arraylist works and techniques to use them 
3     *  intelliJ asked if I wanted to import java.util.ArrayList when the first few lines were 
4     *  entered 
5     */
6    
7    package arraylistplay;
8    
9    import java.util.ArrayList;
10   
11   public class Primes {
12   
13       public static void main(String[] args) {
14   
15           ArrayList<Integer> primes = new ArrayList<>();
16   
17           primes.add(2);
18           primes.add(3);
19           primes.add(5);
20           primes.add(7);
21   
22           System.out.println("size of primes list = " + primes.size());
23           System.out.println("first prime = " + primes.get(0));
24           System.out.println("last prime = " + primes.get(3));
25           System.out.println("last prime = " + primes.get(primes.size() - 1));
26   
27           System.out.println("\nThe intitial list ...");
28           for (Integer prime : primes) {
29               System.out.println(prime);
30           }
31   
32           int temp = primes.get(0);
33           primes.set(0, primes.get(primes.size() - 1));
34           primes.set(primes.size() - 1, temp);
35   
36           System.out.println("\nThe final list ...");
37           for (Integer prime : primes){
38               System.out.println(prime);
39           }
40       }
41   }
42