Mockito Essentials

Getting started with mock objects

A mock object is a combination of a spy and a stub. It acts as an indirect output for a code under test, such as a spy, and can also stub methods to return values or throw exceptions, like a stub. A mock object fails a test if an expected method is not invoked or if the parameters of the method don't match.

The following steps demonstrate the test failure scenario:

1. Launch Eclipse, open <work_space>, and go to the 3605OS_TestDoubles project.
2. Create a com.packt.testdoubles.mock package and a StudentService class. This class will act as a course register service. The following is the code for the StudentService class:

   public class StudentService {
   
     private Map<String, List<Student>> studentCouseMap = new HashMap<>(); ...