Unit Testing with JUnit

This course gives you hands-on experience with JUnit 5’s full feature set, including annotations, assertions, and mocking with Mockito. You will learn how to write effective tests for complex Java applications covering IO, DAO, and multi-threaded code, and discover how test-driven development can raise the quality and reliability of your software.

Unit Testing Principles

Gain a thorough understanding of what unit testing is, its role in producing reliable software, and why it matters throughout the development lifecycle. You will explore how well-structured tests improve code quality, how assertions validate behaviour, and how coverage metrics measure effectiveness. This module also covers practical guidelines for writing maintainable tests that catch defects early and reduce technical debt over time.

JUnit 5 Fundamentals

Build a strong working knowledge of JUnit 5, from its core capabilities to the advantages of its modular architecture. You will see how the framework integrates with widely used IDEs and build tools, making testing a natural part of your workflow. The module covers writing, organising, and executing tests using annotations, assertions, and configuration options that balance flexibility with control.

Assertions and Assumptions

Develop confidence in applying JUnit’s assertion and assumption features to make your tests more accurate and purposeful. You will work with tools such as assertAll to group related checks, assertTimeout to validate performance thresholds, and conditional execution using assumeTrue and assumeFalse. These techniques will help you write focused tests that clearly express intent and avoid unnecessary failures that slow down development.