1    /* 
2     * Program to become more acquainted with ArrayList processing, and the basic concepts and mechanisms associated with it. 
3     */
4    
5    package arraylistplay;
6    
7    import java.util.ArrayList;
8    
9    public class Primes {
10   
11       public static void main(String[] args) {
12   
13           ArrayList<Integer> primes = new ArrayList<>();
14   
15           primes.add(2);
16           primes.add(3);
17           primes.add(5);
18           primes.add(7);
19   
20           System.out.println("size of primes list = " + primes.size());
21           System.out.println("first prime = " + primes.get(0));
22           System.out.println("first prime = " + primes.get(3));
23           System.out.println("last prime = " + primes.get(primes.size()-1));
24   
25           System.out.println("\nThe initial list ...");
26           for (Integer prime : primes) {
27               System.out.println(prime);
28           }
29   
30           int temp = primes.get(0);
31           primes.set(0, primes.get(primes.size()-1));
32           primes.set(primes.size()-1, temp);
33   
34           System.out.println("\nThe final list ...");
35           for ( Integer prime : primes ) {
36               System.out.println(prime);
37           }
38       }
39   }
40