SENG 275 ASSIGNMENT 3

SENG 275 ASSIGNMENT 3 (6%)

Total Marks: 44 M
Supplement with code screenshots, diagrams, tables,
graphs, and charts wherever applicable.
Q1) You have been provided with an Assignment 3 code/repository named a3 on brightspace under
assignments, which contains the application and test files necessary for this question. Please push
assignment 3 on GitLab when you complete it. (30M)
Student numbers at Uvic are formatted according to a series of rules. Each student number begins with
an uppercase V and is followed by exactly eight digits.
It is sometimes necessary to look up the name of a student, given only a student number. To do so, the
software system below can be used, which has been partially implemented in the file
lib/src/main/java/a3/a3.java. The outlines of tests have been created for you in
lib/src/test/java/a3/A3Test.java.
Users of the Registration class can provide a Uvic ID number (as a string) to name(), and will get a
string back containing the student’s First Name, followed by a space, followed by their last name.
You have been asked to test the two functions in the Registration class. Unfortunately, the code is in an
unfinished state. Specifically, the StudentDatabaseConnect class exists only as an interface, and the
database itself won’t be ready for some time. Additionally, the name() function is incomplete – it does
not yet fulfill its Design by Contract obligations. Finally, there are no tests written yet.
 class: Registration
 isValidIDNumber()
 name()
 Class:
StudentDatabaseConnection
 nameFromIDNumber()
 isConnected()
You may assume that the following are valid students, and would be in the database if it were
connected:
Student Number Student name
V11111111 Andy Apple
V22222222 Betty Banana
V33333333 Cathy Cantaloupe
V44444444 Donald Durian
1. You must identify the code under test and set up one or more Test Doubles correctly. Use the
Mockito framework for this and refer to Lab 6 as necessary. (8 marks)
2. You must complete the Registration.name() function, implementing its pre- and post- conditions
correctly using Design by Contract principles. Refer to Lab 7 part 1 as necessary. You may not modify
any other code in a3.java; you may only add the code to Registration.name() that is necessary to fulfill
the contract. (4 marks)
3. You must write non-property (regular individual or parameterized Junit) tests to test the following
behavior:
• Does name() have the expected behavior when the database is not connected? (2 marks)
• Does name() have the expected behavior when the database is connected, but the IDs do not fit
the format of Uvic user IDs? Think about the rules above, and what sorts of edge cases there
are. (3 marks)
• Does name() function correctly for students who are in the database? (In other words, are in the
table above?) (3 marks)
• Does name() function correctly for valid student numbers that have no corresponding student in
the table above? (In other words, the student numbers are formatted correctly, but do not appear
in the table). (2 marks)
You will need to read over the specifications for the functions in a3.java to determine the correct
expected behavior for these tests. Each of these tests must establish not only that you obtained the
correct output from the function, but also that the system performed in the correct way – in other
words, you must use Mocks rather than Stubs (and therefore you must verify() that the function calls
you expected occurred, and that no other interactions with your test doubles occurred).
4. You must write property tests (using Jquik) to test the function Registration.isValidIDNumber().
Note that this is a static function, so you won’t need test doubles or verify calls to complete this task.
Specifically, you must:
• Write a test that checks one thousand valid Uvic ID numbers, generated randomly, and confirms
that the function accepts them. (4 marks)
• Write a test that checks one thousand invalid Uvic ID numbers, each of which is made up of a
lowercase letter followed by a number from 10000000 to 99999999. The sections of the Jquik
user guide at https://jqwik.net/docs/current/user-guide.html on parameter generation will be
helpful here. (4 marks)
You will complete your work for part 2 above in a3.java, and for parts 1, 3 and 4 in A3Test.java, in the
sections indicated by comments.
You must submit as part of your assignment 3 pdf:
• A screenshot of your finished Registration.name() function from a3.java, showing the additions
you made to fulfill the pre- and post-conditions.
• A screenshot of your code from A3Test.java, showing your tests. Take multiple screenshots if
necessary to show all your tests.
• A screenshot of your test results from IntelliJ (in the bottom left corner of your screen),
showing all your tests passing. Please expand tests that have been grouped together using the
Expand All button above the tests results window.
Note: Please contact shujamughal@uvic.ca for any clarification regarding the above question.

Q2) Consider a function called ComplexAddition() which is part of the Calculator class used in the
lectures on mutation testing. Submit the answer in Brightspace as a pdf file. (14M)
public int ComplexAdd(int a, int b)
{
if (a<2)
{
return (a+b) * -1;
}
else
{
return a+b;
}
}
a) Write JUnit test cases to give 100% line coverage. (4M)
b) Perform Mutation testing on this function. List all mutations done by the system. Submit the
screenshot of Mutations. (2M)
c) Write additional JUnit test cases to strengthen your test suite to kill all mutants. Specify which test
case kills which mutant. Submit screenshots after killing each mutant. (6M)
d) What is the final test suite? Are you able to achieve 100% mutation coverage? (2M)