Implementing Classes - Java Concepts - page 173

΢΢Exercise P3.5. Implement a class Car with the following properties. A car
has a certain fuel efficiency (measured in miles/gallon or liters/kmȌpick
one) and a certain amount of fuel in the gas tank. The efficiency is
specified in the constructor, and the initial fuel level is 0. Supply a method
drive that simulates driving the car for a certain distance, reducing the
amount of gasoline in the fuel tank. Also supply methods
getGasInTank , returning the current amount of gasoline in the fuel
tank, and addGas , to add gasoline to the fuel tank. Sample usage:

Car myHybrid = new Car(50); // 50 miles per gallon
myHybrid.addGas(20); // Tank 20 gallons
myHybrid.drive(100); // Drive 100 miles
double gasLeft = myHybrid.getGasInTank(); // Get
gas remaining in tank

You may assume that the drive method is never called with a distance that
consumes more than the available gas. Supply a CarTester class that
tests all methods.

΢΢Exercise P3.6. Implement a class Student . For the purpose of this
exercise, a student has a name and a total quiz score. Supply an appropriate
constructor and methods getName() , addQuiz(int score) ,
getTotalScore() , and getAverageScore() . To compute the
latter, you also need to store the number of quizzes that the student took.

Supply a StudentTester class that tests all methods.

΢ Exercise P3.7. Implement a class Product . A product has a name and a
price, for example new Product(ÑToasterÑ, 29.95) . Supply
methods getName , getPrice , and reducePrice . Supply a program
ProductPrinter that makes two products, prints the name and price,
reduces their prices by $5.00, and then prints the prices again.

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΢΢Exercise P3.8. Provide a class for authoring a simple letter. In the
constructor, supply the names of the sender and the recipient:

public Letter(String from, String to)

Supply a method