Black
and White Box Tests
Please have a look at black-box
and white-box
testing before class.
- Getting started:
Together with your team write down the equivalence classes for
testing a method that returns the absolute value of an integer
passed in as a parameter using the black-box methodology. Don't
peek at the code yet! Now download the implementation absolute.java
and give the equivalence classes for a white-box test. Develop
one test case for each equivalence class. Now implement the
test case using JUnit, if you are programming in Java. You are
welcome, however, to use any programming language you wish.
- Black-box test: Look
at this grading scale at the bottom of the page. Give the
equivalence classes for a program that loops until a -1 is
entered, asking for the number of points on this scale, prints
the appropriate letter grade (A-F), and then prints the
average number of points when -1 has been entered. Develop one
test case for each equivalence class. Test your test cases
with GradingScale.class—this
is a Java program. No fair decompiling the class! Report on
the results. Did you find any errors? Document the errors
found, but don't correct the code.
Grading Scale (Points = Procent)
| Points |
Grade |
ECTS |
Points |
Grade |
ECTS |
| 95-100 |
1,0 |
A |
65-69 |
3,0 |
Cs |
| 90-94 |
1,3 |
A |
60-64 |
3,3 |
C |
| 85-89 |
1,7 |
B |
55-59 |
3,7 |
D |
| 80-84 |
2,0 |
B |
50-54 |
4,0 |
D |
| 75-79 |
2,3 |
B |
0-49 |
5,0 |
F |
| 70-74 |
2,7 |
C |
|
|
|
- White-box test /
path coverage: Examine the code for TaxTime.java.
Draw a code graph of the main class! How many independent
paths are there? What are the conditions that cause each of
the paths to be taken? Draw up a table giving you an overview
of the conditions. Design and implement test cases that
exercise each path. Are there any errors in the program
(besides the size of the tax bite)? Document the errors found,
don't correct the code.
- Test Cases: Define
some test cases (at least one per team member) for your
Shopping List App!
- Reflection: Consider
the examples TaxTime and GradingScale. What makes these
programs hard to test? How would you refactor TaxTime to make
it testable automatically with JUnit?
Your report, including all source code,
is due next week and should include all materials. Don't forget
to include your names on your report, and post the materials in
the Moodle area for each team member.