Defining jUnit Test cases Correctly
- by Epitaph
I am new to Unit Testing and therefore wanted to do some practical exercise to get familiar with the jUnit framework.
I created a program that implements a String multiplier
public String multiply(String number1, String number2)
In order to test the multiplier method, I created a test suite consisting of the following test cases (with all the needed integer parsing, etc)
@Test
public class MultiplierTest {
Multiplier multiplier = new Multiplier();
// Test for 2 positive integers
assertEquals("Result", 5, multiplier.multiply("5", "1"));
// Test for 1 positive integer and 0
assertEquals("Result", 0, multiplier.multiply("5", "0"));
// Test for 1 positive and 1 negative integer
assertEquals("Result", -1, multiplier.multiply("-1", "1"));
// Test for 2 negative integers
assertEquals("Result", 10, multiplier.multiply("-5", "-2"));
// Test for 1 positive integer and 1 non number
assertEquals("Result", , multiplier.multiply("x", "1"));
// Test for 1 positive integer and 1 empty field
assertEquals("Result", , multiplier.multiply("5", ""));
// Test for 2 empty fields
assertEquals("Result", , multiplier.multiply("", ""));
In a similar fashion, I can create test cases involving boundary cases (considering numbers are int values) or even imaginary values.
1) But, what should be the expected value for the last 3 test cases above? (a special number indicating error?)
2) What additional test cases did I miss?
3) Is assertEquals() method enough for testing the multiplier method or do I need other methods like assertTrue(), assertFalse(), assertSame() etc
4) Is this the RIGHT way to go about developing test cases? How am I "exactly" benefiting from this exercise?
5)What should be the ideal way to test the multiplier method?
I am pretty clueless here. If anyone can help answer these queries I'd greatly appreciate it. Thank you.
