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Pragmatic Unit Testing in Java 8 with JUnit
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Explore writing unit tests for Java applications using JUnit, delve into JUnit organization, assertions, quality practices, design relevance, refactoring, and using mock objects for dependencies.

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In this course, you will learn how to write a unit test for Java applications using JUnit. You'll start by covering unit-testing foundations, which provide you with a starter set of information about writing basic tests in JUnit. You’ll learn about JUnit organization and assertions, and you’ll pick up a few core quality practices for unit testing such as the Right BICEP and the CORRECT way. Towards the end, the bigger design picture focuses on the relevance of design to unit testing and vice versa. You’ll...Show More

In this course, you will learn how to write a unit test for Java applications using JUnit. You'll start by covering unit-testing...Show More

WHAT YOU'LL LEARN

Learn how to effectively test Java applications using JUnit

Get to know the core quality principles of unit testing

Master writing cleaner and refactored JUnit tests

Learn how to effectively test Java applications using JUnit

Content

102 Lessons26 Quizzes

Before We Begin

3 Lessons

Get familiar with pragmatic unit testing principles, JUnit practices, and their benefits.

Why This Course?

Course Structure

Why Unit Testing?

JUnit Test Foundations

8 Lessons

Get started with foundational JUnit concepts, writing unit tests, and maintaining test clarity.

Reasons to Write Unit Tests

Introduction to Building JUnit Test

Our First Passing Test

Arrange, Act, and Assert Your Way to a Test

Understanding What We’re Testing: The Profile Class

Let's Write Tests

Initializing Tests with @Before Methods

Quiz on JUnit Test Bits

Digging Deeper into JUnit Assertions

9 Lessons

Break apart critical JUnit assertions, styles, decorators, floating-point comparisons, and exception handling techniques.

Introduction to Assertions in JUnit

A Classic-Style Assertion: assertTrue

Hamcrest Assertions

Decorators

Comparing Two Floating-Point Numbers

Assertion Messages

Testing the Expected Exceptions

Expected Exceptions using JUnit

Quiz Time

Organizing Your Tests

8 Lessons

Break down complex ideas for organizing and optimizing unit tests in JUnit.

Follow the AAA Pattern

Test Behaviors not Methods

Relationship Between Test and Production Code

Focused and Single-purpose Tests

Mastering Manic Mnemonics!

7 Lessons

Deepen your knowledge of the FIRST principles to enhance unit test effectiveness and reliability.

FIRST: Properties of Good Tests

[F]IRST: [F]ast

F[I]RST: [I]solate Your Tests

FI[R]ST: Good Tests Should Be [R]epeatable

FIR[S]T: [S]elf-Validating

FIRS[T]: [T]imely

Quiz Time

What to Test: The Right-BICEP

8 Lessons

Investigate the Right-BICEP technique for structured unit testing, focusing on correctness, boundaries, inverses, cross-checks, errors, and performance.

The Right-BICEP

[Right]-BICEP: Are the Results Right?

Right-[B]ICEP: Boundary Conditions

Right-B[I]CEP: Checking Inverse Relationships

Right-BI[C]EP: Cross-Checking Using Other Means

Right-BIC[E]P: Forcing Error Conditions

Right-BICE[P]: Performance Characteristics

Quiz time

Boundary Conditions: The CORRECT Way

8 Lessons

Piece together the parts of evaluating boundary conditions using the CORRECT acronym for thorough testing.

The CORRECT Way

[C]ORRECT: [C]onformance

C[O]RRECT: [O]rdering

CO[R]RECT: [R]ange

COR[R]ECT: [R]eference

CORR[E][C]T: [C]ardinality and [E]xistence

CORREC[T]: [T]ime

Quiz time

The Bigger Design Picture

5 Lessons

Try out refactoring techniques to optimize code clarity and maintainability using JUnit tests.

Refactoring to Cleaner Code

Finding Better Homes for Our Methods

Automated and Manual Refactorings

How much Refactoring?

Quiz time

Bigger Design Issues

6 Lessons

Get started with applying SOLID principles, command-query separation, and optimizing test maintenance for better design.

SOLID class design principles

The SRP and Profile class

Command-query separation principle

Test Maintenance Cost

Other Design Thoughts

Quiz Time

10.

Using Mock Objects

7 Lessons

Break apart the use of mock objects to streamline and improve unit testing.

A Testing Challenge

Replacing Troublesome Behavior with Stubs

Changing Our Design to Support Testing

Simplifying Testing using a Mock Tool

One Last Simplification: Introducing an Injection Tool

What’s Important to Get Right When Using Mocks?

Quiz Time

11.

Refactoring Tests

10 Lessons

Enhance your skills in refactoring tests to improve readability, maintainability, and effectiveness.

Searching for an Understanding

Test Smell: Unnecessary Test Code

Test Smell: Missing Abstractions

Test Smell: Irrelevant Information

Test Smell: Bloated Construction

Test Smell: Multiple Assertions

Test Smell: Irrelevant Details

Test Smell: Implicit Meaning and Misleading Organization

Adding a New Test

Quiz Time

12.

The Bigger Unit-Testing Picture

10 Lessons

Dig deeper into Test-Driven Development, its cycle, incremental coding, refactoring, and effective test documentation.

Test-Driven Development

TDD Cycle

Smallest Possible Increment

Code Refactoring

Another Small Increment

Supporting Multiple Answers: A Small Design Detour

Expanding the Interface

Last Tests

Tests As Documentation

Quiz Time

13.

Testing Some Tough Stuff

6 Lessons

Tackle testing challenges in multithreaded code, application logic extraction, database testing, and mocking controllers.

Testing Multithreaded Code

Extracting Application Logic

Redesigning the Threading Logic

Testing Databases

The Data Problem

Cleaning the Database and Mocking the Controller

14.

Testing on a Project

4 Lessons

Piece together the parts of unit testing, team standards, CI, and code coverage.

Coming up to Speed

One Team, One Unit

Convergence with Continuous Integration

Code Coverage

15.

Wrapping Up

1 Lessons

Get familiar with applying unit testing techniques in practice and continuously refining skills.

Conclusion

16.

Appendix - Setting up JUnit

2 Lessons

Unpack the core of setting up JUnit in IntelliJ IDEA and NetBeans.

IntelliJ IDEA

NetBeans

Certificate of Completion

Showcase your accomplishment by sharing your certificate of completion.

Course Author:

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Pragmatic Unit Testing in Java 8 with JUnit Save

Pragmatic Unit Testing in Java 8 with JUnit
Save