Test driven development in Java with Mockito Framework

Explore what mocking is and why it exists in test driven development. Discover how mocking isolates tests from external dependencies, speeds test runs, and lets you control simulated service behavior.

Learn how test driven development starts by writing tests before code, then creates code to pass them, refactors, and demonstrates reduced bugs and faster development with username validation examples.

Explore stubs, test doubles, and mocks, where stubs provide predefined responses to replace dependencies, and mocks enable behavior verification of method calls and parameters.

Learn how to write your first mock with Mockito in a Java unit test, mock a database dependency, initialize mocks, and configure doReturn to simulate responses.

Learn how to use the @InjectMock annotation to inject a mocked database into the service under test and simplify test setup.

Learn how the Mockito extension for Jupiter tests eliminates mock initialization boilerplate by annotating the test class, letting mocks be auto-initialized and simplifying test code.

Learn how to create mocks with the mock method using Mockito, inject them into a service, and mock database responses without annotations for faster unit testing.

Verify behavior using Mockito to confirm that the service calls getUsernameFromDatabase on the mock with the correct arguments, or remains uninvoked when the user id is zero.

Learn to verify the number of interactions with mocks in Mockito by using verify with times(n) and optional argument checks, illustrating mock setup, stubbing, and verification.

Discover advanced verify methods in Mockito, such as at least, at most, at least once, and at most once, and learn how to flexibly validate interaction counts in tests.

Verify that an interaction has not occurred using Mockito with times(0) or the never method on a mock, and learn when to apply never as an alternative.

Learn to verify that no interactions occurred on a mock object using Mockito's verify no interactions, contrasted with verifying specific method calls, and apply it in unit tests.

Master behavior verification with Mockito by using verify no more interactions to ensure no further mock calls occur when the current age equals the new age.

Learn to verify the order of method execution in Mockito tests using InOrder, ensuring interactions like get user and save user occur in the intended sequence.

Learn how to verify exceptions in Java with Mockito by testing negative scenarios, using when and then through for non-void and void methods, and validating exception handling.

Demonstrate mocking a void method to throw a database exception with Mockito in Java tests for test-driven development.

Master argument matchers in mock setups with Mockito’s any variants for flexible inputs. Learn to return values for any string, any int, and any object, and verify calls.

Learn how to use argument matchers in Mockito for all arguments in stubbing and verification, including combining fixed values with any string, and why you should apply the rule consistently.

Explore how to use ArgumentCaptor in Mockito to capture mock arguments for later assertions. Create an ArgumentCaptor instance or use the @Captor annotation to verify values like user name.

Learn how spy objects in Mockito enable partial, verifiable behavior by tracking method calls while potentially calling real methods, contrasting spies with mocks, and understanding when to use them.

Learn to create spy objects with Mockito, stop certain method calls while allowing real ones, and verify interactions, using both programmatic spies and annotation-based spies.

Discover the course bonus by browsing discounted offers on the instructor's site, apply active coupon codes, and explore the lowest prices across Udemy courses.