Primes.java
1    /* 
2     * Creating an array list with the first four prime numbers. 
3     */
4    
5    package arraylistplay;
6    
7    import java.util.ArrayList;
8    
9    public class Primes {
10       public static void main(String[] args) {
11   
12           ArrayList<Integer> primes = new ArrayList<>();
13   
14           primes.add(2);
15           primes.add(3);
16           primes.add(5);
17           primes.add(7);
18   
19           System.out.println("size of primes list = " + primes.size());
20           System.out.println("first prime = " + primes.get(0));
21           System.out.println("last prime = " + primes.get(3));
22           System.out.println("last prime = " + primes.get(primes.size()-1));
23   
24           System.out.println("\nThe Initial List ...");
25           for ( Integer prime : primes ) {
26               System.out.println(prime);
27   
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