CS1 Standard Demo Page

size of primes list = 4
first prime = 2
last prime = 7
last prime = 7

The initial list ...
2
3
5
7

The final list ...
7
3
5
2/*
 * Arrays with primes.
 */
package arraylistplay;

import java.util.ArrayList;

/**
 *
 * @author dmaslows
 */
public class Primes {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {

        ArrayList primes = new ArrayList<>();

        primes.add(2);
        primes.add(3);
        primes.add(5);
        primes.add(7);

        System.out.println("size of primes list = " + primes.size());
        System.out.println("first prime = " + primes.get(0));
        System.out.println("last prime = " + primes.get(3));
        System.out.println("last prime = " + primes.get(primes.size() - 1));

        System.out.println("\nThe initial list ...");
        for (Integer prime : primes) {
            System.out.println(prime);
        }

        int temp = primes.get(0);
        primes.set(0, primes.get(primes.size() - 1));
        primes.set(primes.size() - 1, temp);

        System.out.println("\nThe final list ...");
        for (Integer prime : primes) {
            System.out.println(prime);
        }

    }
}