1  /**

  2     This program demonstrates the measurable BankAccount and Country classes.

  3  */

  4  public class MeasurableDemo

  5  {

  6     public static void main(String[] args)

  7     {

  8        Measurable[] accounts = new Measurable[3];

  9        accounts[0] = new BankAccount(0);

 10        accounts[1] = new BankAccount(10000);

 11        accounts[2] = new BankAccount(2000);

 12  

 13        System.out.println("Average balance: " 

 14           + average(accounts));

 15  

 16        Measurable[] countries = new Measurable[3];

 17        countries[0] = new Country("Uruguay", 176220);

 18        countries[1] = new Country("Thailand", 514000);

 19        countries[2] = new Country("Belgium", 30510);

 20  

 21        System.out.println("Average area: " 

 22           + average(countries));

 23     }

 24  

 25     /**

 26        Computes the average of the measures of the given objects.

 27        @param objs an array of Measurable objects

 28        @return the average of the measures

 29     */

 30     public static double average(Measurable[] objs)

 31     {

 32        if (objs.length == 0) { return 0; }

 33        double sum = 0;

 34        for (Measurable obj : objs)

 35        {

 36           sum = sum + obj.getMeasure();

 37        }

 38        return sum / objs.length;

 39     }

 40  }