testing

In this article, we will learn different ways to improve test readability. Tests document how the system should behave. They also act as self-verifying executable specifications.

Learn how to use the test data builder pattern to make it easy to create objects for tests. Learn how to reduce boilerplate code with Lombok.

What are the DRY and DAMP principles? Why do people consider DRY and DAMP in tests contradictory and how can we achieve both?

What is the best way to test private methods? Should I use some library or use reflection? Can I just make the method public?

Learn how to use the Mockito mocking framework with JUnit 5. Learn both the test framework independent way, and using the Mockito JUnit 5 extension.

Learn how to run code before and after each test or all tests in the test class. Also learn the execution order of lifecycle methods in different cases.

Learn how to assert an exception is thrown using JUnit 5. Also, learn how to check the error message of the thrown exception.

Learn how to write JUnit 5 parameterized tests. Learn answers to some of the most asked questions about parameterized tests.

Learn how to write and run a simple JUnit 5 test. Setup preconditions, interact with the object we want to test, and verify that it behaves like expected.

Learn how to verify test results using JUnit 5 assertions. Learn the basic assertion methods, error message customization and assertion grouping.