1    /* 
2     * The first four primes, set into an array. 
3     */
4    
5    package arrayplay;
6    
7    public class Primes {
8        public static void main(String[] args){
9            int[] primes = new int[4];
10           primes[0] = 2;
11           primes[1] = 3;
12           primes[2] = 5;
13           primes[3] = 7;
14           System.out.println("length of primes array = "+primes.length);
15           System.out.println("first prime = "+primes[0]);
16           System.out.println("last prime = "+ primes[3]);
17           System.out.println("last prime = "+ primes[primes.length-1]);
18   
19           System.out.println("\nThe initial array ...");
20           int i = 0;
21           while ( i < primes.length ) {
22               System.out.println(primes[i]);
23               i = i + 1;
24           }
25           int temp = primes[0];
26           primes[0] = primes [primes.length-1];
27           primes[primes.length-1] = temp;
28   
29           System.out.println("\nThefinal array ...");
30           for (int x = 0; x < primes.length; x=x+1) {
31               System.out.println(primes[x]);
32           }
33       }
34   }
35