Program 7.13: A Car class that implements Import

To actually use this interface you create a class that includes a public double calculate_tariff() method and declare that the class implements Import. For instance here's one such class:

class Car implements Import {

  String make;
  String model;
  int year;
  int max_speed;
  int weight
  float price;
  int num_passengers;
  int num_wheels = 4;
  int num_doors;

  public double calculate_tariff() {
    return price * 0.1;


Copyright 1996 Elliotte Rusty Harold
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