CarTest.java Questions

Instructions

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Program listing

// REFERENCES TUTORIAL
// Copyright (C) 2001 Davin Pearson
// Website: http://www.davinpearson.com

class Car {

    /*
     * Properties of the class...
     */
    private String     model;
    public  int        value;
    private int        serialNumber;
    private static int serial = 0;

    /*
     * Constructor of the class...
     */
    public Car(String aModel, int aValue) {

       model  = aModel;
       value  = aValue;

       serialNumber = serial;

       serial++;
    }

}

class Driver {

    /*
     * Properties of the class...
     */
    private String     name;
    private int        money;
    private Car        ownersCar;

    /*
     * Constructor of the class...
     */
    public Driver(String aName, int aMoney) {
       name   = aName;
       money  = aMoney;
    }
}

class CarTest {

    /*
     *
     * The main method is the point of entry into the program...
     *
     */
    public static void main(String[] args) {

       Car f = new Car("Ford Escort",1000);
       Car n = new Car("Nissan Nivara",2000);

       Driver joe  = new Driver("Joe Bloggs",500);
       Driver mark = new Driver("Mark Smith",600);

       Car joesCar = new Car("Ford Escort",1000);
       joe.purchase(joesCar);

       mark.stealCarFrom(joe);

       mark.smashCar();                 // halves the value of
                                        // Mark's car.

       Driver.swapMoney(joe,mark);

       Driver.swapCars(joe,mark);

       Car.swapSerialNumbers(f,n);      // Swaps the serial numbers
                                        // of the cars.

       Car joesTradeIn = new Car("Datsun Coupe", 3000);
       joe.tradeIn(joesTradeIn);
                                        // Joe gets
                                        // half the value
                                        // of his old car

       joe.sellCarTo(mark);

       System.out.println("Joe's net worth = " + joe.netWorth());
                                        // Prints out Joes' money
                                        // plus the value of his
                                        // car, if he has a car.
      
   }

}

// QUESTIONS:
//
// (1) What does the line "serial++" do in the constructor for class Car?
// 
// (2) Write toString methods for the Car and Driver classes so that
// you use them in the next question for debugging.
// 
// (3) Write the methods listed in the main method. 
//
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