Test-Driven Development in Java, JUnit, and Mockito | CodeSignal Learn

intermediate

Test-Driven Development in Java, JUnit, and Mockito

Back-end Engineering

4 courses

99 practices

13 hours

Master TDD in Java using JUnit - write tests first, implement code, and refactor. Learn test doubles with the Mockito framework to isolate components. Create cleaner, more maintainable code while reducing bugs and improving development efficiency.

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Earn a shareable

Certificate of Achievement

Verified skills you'll gain

INTERMEDIATE

Programming, Algorithms, and Data Structures

INTERMEDIATE

Computer Science Fundamentals

Tools you'll use

Java

JUnit

Mockito

Trusted by learners working at top companies

Course 1

Foundations of TDD in Java with JUnit: The Principles

6 lessons

27 practices

This course introduces Test-Driven Development (TDD) for Java projects, covering the Red-Green-Refactor workflow, TDD mindset, and setup with JUnit. Learn best practices like SOLID principles and dependency injection, and explore TDD's impact on code quality and speed compared to traditional approaches.

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Course 2

Red-Green-Refactor: Practicing TDD with Java & JUnit

5 lessons

25 practices

This course focuses on practicing the core TDD workflow: "Red-Green-Refactor." You'll write failing tests (Red), implement code to pass them (Green), and refactor while keeping tests passing (Refactor). No new concepts are introduced—just hands-on practice with various requirements to sharpen your TDD skills.

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Course 3

Isolating Dependencies with Test Doubles using JUnit & Mockito

5 lessons

26 practices

Discover the pivotal role of test doubles in modern software testing. This introductory course will guide you through the essentials of dummies, stubs, spies, mocks, and fakes. Learn how these powerful tools help you isolate units under test, control behavior, and build reliable, fast, and maintainable tests. Step into the world of test doubles and elevate your software development skills.

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Course 4

Refactoring by Leveraging Tests with Java & JUnit

5 lessons

21 practices

This course focuses on the Refactor step in TDD, teaching developers to spot code smells and resolve them through refactoring. Using real-world examples, you'll identify common issues, apply refactoring techniques, and ensure functionality is preserved with existing tests.

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