CSC1016S Assignment 2: Introduction to objects and classes

Assignment Instructions

This assignment involves constructing programs in Java using class declarations to model simple

types of object. It also involves the use of software testing as a means of guiding problem analysis,

solution design and evaluation.

Exercise One [25 marks]

This question concerns (i) writing a Student class to model a student's name, composed of a first

name, middle name and last name, and (ii) using a supplied test suite to drive the process.

The Student class should meet the following specification:

Class Student

A Student object represents a student. A student has a first name, middle name and last name.

Instance variables

private String firstName;

private String middleName;

private String lastName;

Methods

public void setNames(String first, String middle, String last)

// Set the first, middle and last names of this Student object.

public String getFullName()

// Obtain the full name of this Student with the middle name converted to an initial only.

Thinking of the problem in terms of testing, there are three requirements that must be met:

A. The setNames() method sets the names stored in the object i.e. the values of

firstName, middleName, lastName.

B. The getFullName() method obtains the name of the student with the middle name

converted to an initial only.

C. The getFullName() method does not change anything - i.e. it does not modify the values of

firstName, middleName, lastName.

Note that, these requirements are interdependent i.e. you can only check setNames() works by

using getFullName(), and you can only check getFullName() works by first using

setNames().

The program assumes that you 've constructed a Student class, and as its name suggests, it runs

tests on Student objects.

It codes test requirements as a set of two tests: the first test evaluates A and B in conjunction, and

the second test focuses on C.

CONTINUED

We could have written one test covering all three requirements, however, two tests offer a more

precise diagnosis of problems with code.

Use the TestStudent program to develop your Student class:

If a test fails, look at the TestStudent program to see what the test does.

If the tests pass, then your Student class will receive full marks from the automatic marker.

CONTINUED

Exercise Two [25 marks]

This question concerns Uber, in particular, (i) writing an UberService class to model an Uber

service from the point of view of price, and (ii) using a supplied test suite to drive the process.

Consider the following specification for an UberService type of object.

Class UberService

An UberService object represents an Uber service from the point of view of price. (Services differ in

characteristics such as luxury and capacity of the vehicle, and consequently, in price.)

Each service has a base fare, a cost per minute, cost per kilometre, and cancellation fee. The cost of a

journey consists of the base fare + cost for minutes + cost for distance.

Methods

void setDetails(String name, int costPerMin, int costPerKM, int baseFee, int cancellationFee)

// Set the details of this service to the given values.

void setName(String name)

// Set the service name.

String getName()

// Obtain the service name.

void setCostPerMinute(int cents)

// Set the cost per minute.

int getCostPerMinute()

// Set the cost per minute in cents.

void setCostPerKilometre(int cents)

// Set the cost per kilometre.

int getCostPerKilometre()

// get the cost per kilometre in cents.

void setBaseFare(int cents)

// Set the base fare.

int getBaseFare()

// get the base fare in cents.

void setCancellationFee(int n)

// Set the cancellation fee.

int getCancellationFee()

// Obtain the cancellation fee in cents for this service.

double calculateFare(double minutes, double distance)

// Obtain the fare (in the form of a real number of cents) for a journey of the

// given time and distance.

CONTINUED

Thinking in terms of testing, there are a number of requirements that must be met:

A. setDetails() sets the service name, cost per minute, cost per kilometre, base fee and

cancellation fee.

B. setName() sets the service name.

C. setCostPerMinute() sets the cost per minute.

D. setCostPerKilometre() sets the cost per kilometre.

E. setBaseFare() sets the base fare.

F. setCancellationFee() sets the cancellation fee.

G. getName() returns the service name.

H. getCostPerMinute() returns the cost per minute.

I. getCostPerKilometre() returns the cost per kilometre.

J. getBaseFare() returns the base fare.

K. getCancellationFee() returns the cancellation fee.

L. getName() ONLY returns the service name.

M. getCostPerMinute() ONLY returns the cost per minute.

N. getCostPerKilometre() ONLY returns the cost per kilometre.

O. getBaseFare() ONLY returns the base fare.

P. getCancellationFee() ONLY returns the cancellation fee.

Q. calculateFare() obtains the correct fare for the given trip duration and distance.

R. setName() ONLY sets the service name.

S. setCostPerMinute() ONLY sets the cost per minute.

T. setCostPerKilometre() ONLY sets the cost per kilometre.

U. setBaseFare() ONLY sets the base fare.

V. setCancellationFee() ONLY sets the cancellation fee.

W. calculateFare() ONLY obtains the correct fare for the given trip duration and distance.

Of particular note are tests 16 and 17, which evaluate requirements Q and W. The

calculateFare() method returns a real number. To test real numbers for 'equality', we usually

seek to determine whether they are within some margin of error of each other. Hence expressions

such as:

if (Math.abs(service.calculateFare(3.0, 7.0)-28710.0)

...

}

Use the TestUberService class to guide development of the UberService class.

CONTINUED

Exercise Three [25 marks]

This question concerns devising test requirements and writing tests that confirm your understanding

of the behaviour of a Collator type of object as describe in the following specification:

Class Collator

A Collator object has a label and manages information on a sequence of readings. It records the number of

readings, the maximum, the minimum and the average.

Constructors

Collator(String label)

Collator object. The number of readings is set to zero.

Methods

void label(String label)

// Change this Collator's label.

void recordReading(int reading)

// Use the given reading to update the record.

String label()

// Obtain this Collator's label.

int maximum()

// Obtain the largest reading taken. (Assumes numberOfReadings()>0.)

int minimum()

// Obtain the lowest reading taken. (Assumes numberOfReadings()>0.)

double average()

// Obtain the average of readings taken, rounded to the nearest integer. (Assumes

numberOfReadings()>0.)

int numberOfReadings()

// Obtain the number of readings which have been taken.

. Based on thespecification, devise a set of test requirements for this class, and construct a program called

TestCollator that implements tests that satisfy these requirements. You should draw on the

examples provided in questions one and two.

Your program should produce the same form of output as used by TestStudent and

TestUberService.

e.g.

...

Test 10

Pass

Test 11

Fail

...

CONTINUED

Submit TestCollator program to the automatic marker.

The marker will run it against versions of the Collator class that are faulty in various ways.

It also checks that a correct Collator class passes all the tests. If not, then the marker

deducts the full set of marks available for the question.

Exercise Four [25 marks]

Build a program called Meteorology that uses 3 Collator objects, one for temperature, one

for pressure, one for humidity, and that behaves as follows:

Meteorology Program

Make a selection and press return:

1. Record a temperature reading.

2. Record a pressure reading.

3. Record a humidity reading.

4. Print maximum values.

5. Print minimum values.

6. Print average values.

7. Quit.

1

Enter value:

17

Make a selection and press return:

1. Record a temperature reading.

2. Record a pressure reading.

3. Record a humidity reading.

4. Print maximum values.

5. Print minimum values.

6. Print average values.

7. Quit.

4

Maximum temperature: 17

Maximum pressure: -

Maximum humidity: -

Make a selection and press return:

1. Record a temperature reading.

2. Record a pressure reading.

3. Record a humidity reading.

4. Print maximum values.

5. Print minimum values.

6. Print average values.

7. Quit.

2

Enter value:

1020

Make a selection and press return:

1. Record a temperature reading.

2. Record a pressure reading.

3. Record a humidity reading.

4. Print maximum values.

5. Print minimum values.

6. Print average values.

7. Quit.

1

Enter value:

11

CONTINUED

Make a selection and press return:

1. Record a temperature reading.

2. Record a pressure reading.

3. Record a humidity reading.

4. Print maximum values.

5. Print minimum values.

6. Print average values.

7. Quit.

5

Minimum temperature: 11

Minimum pressure: 1020

Minimum humidity: -

Make a selection and press return:

1. Record a temperature reading.

2. Record a pressure reading.

3. Record a humidity reading.

4. Print maximum values.

5. Print minimum values.

6. Print average values.

7. Quit.

3

Enter value:

87

Make a selection and press return:

1. Record a temperature reading.

2. Record a pressure reading.

3. Record a humidity reading.

4. Print maximum values.

5. Print minimum values.

6. Print average values.

7. Quit.

6

Average temperature: 14.00

Average pressure: 1020.00

Average humidity: 87.00

Make a selection and press return:

1. Record a temperature reading.

2. Record a pressure reading.

3. Record a humidity reading.

4. Print maximum values.

5. Print minimum values.

6. Print average values.

7. Quit.

7

Marking and Submission

Submit the Student.java, UberService.java, TestCollator.java, and Meteorology.java files contained

within a single .ZIP folder to the automatic marker. The zipped folder should have the following

naming convention: