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.

Pragmatic Unit Testing in Java 8 with Junit by The Pragmatic Programmer.png

junit.tar.gz

java

test2

test4 - Our first passing test

test6

test14

test16-branch-persistence

AssertTest-13

test15

test15-profile

test15-ProfilePoolTest

test16-BearingTest

test16-RectangleTest

test16-SparseTest

test16-TransmissionTest

test16-ProfileTest

test20m-ProfileTest

test21-Profile

big1-Profile

big1-MatchSet

big4-MatchSetTest

big4-MatchSet

big6

mock-2-AddressRetrieverTest

mock-4-AddressRetrieverTest

mock-5-AddressRetrieverTest

test1-SearchTest

test3-SearchTest

tdd-1-ProfileTest.java 

tdd-2-ProfileTest.java

tdd-3-ProfileTest.java

tdd-4-Profile.java

tdd-5-ProfileTest.java

tdd-9-ProfileTest.java

tdd-10-ProfileTest.java

tdd-10-AnswerTest.java

tdd-11-ProfileTest.java

tdd-12-ProfileTest.java

tdd-14-ProfileTest.java

tdd-15-ProfileTest.java

thread-2-ProfileMatcherTest

thread-3-ProfileMatcherTest

thread-4-ProfileMatcherTest

test16-branch-persistence-redesign-QCTest

AssertHamcrest-13

test16-branch-persistence-redesign-StatCompilerTest

test16-ProfilePoolTest

test15-ProfilePoolTest-copy 16

test3-SearchTest-ContainsMatches

tdd-11-ProfileTest.java-Supporting Multiple Answers

thread-2-ProfileMatcherTest-Testing Multithreaded Code

test2-Our First passing test

test4 - AAA your way to a test

test2-final-intro-junit

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 refactor your tests, and you’ll learn how to use mock objects to deal with trouble-some dependencies.

Pragmatic Unit Testing in Java 8 with JUnit

## FIRST principle
We can avoid many of the pitfalls that unit testers often fall into by following the `FIRST` principles of unit testing:


* [**F**]**ast**: Unit tests should be fast
* [**I**]**solated**: Unit tests should be written so they don't depend on other test cases.
* [**R**]**repeatable**: Unit tests should produce the same result over time.
* [**S**]**elf-validating**: Output should be determined by each test.
* [**T**]**imely**: We can write unit tests at any time.

The word “first” itself has significant meaning in the context of unit testing.

## Test-driven development
Right now, it's likely you’re writing code first then writing unit tests after the fact. Perhaps surprisingly, we can get different results if we write the unit tests *before* we write the corresponding code. A host of folks practice this discipline known as **test-driven development (TDD)**.

>The sole delineation between plain ol’ unit testing (POUT) and TDD is that the tests come first in TDD.

Whether we write tests first or last, we’ll go farther with them if we adhere to the FIRST principles.

# FIRST principle
We can avoid many of the pitfalls that unit testers often fall into by following the `FIRST` principles of unit testing:


* [**F**]**ast**: Unit tests should be fast
* [**I**]**solated**: Unit tests should be written so they don't depend on other test cases.
* [**R**]**repeatable**: Unit tests should produce the same result over time.
* [**S**]**elf-validating**: Output should be determined by each test.
* [**T**]**imely**: We can write unit tests at any time.

The word “first” itself has significant meaning in the context of unit testing.

# Test-driven development
Right now, it's likely you’re writing code first then writing unit tests after the fact. Perhaps surprisingly, we can get different results if we write the unit tests *before* we write the corresponding code. A host of folks practice this discipline known as **test-driven development (TDD)**.

>The sole delineation between plain ol’ unit testing (POUT) and TDD is that the tests come first in TDD.

Whether we write tests first or last, we’ll go farther with them if we adhere to the FIRST principles.

Learn the principle of the FIRST acronym in writing good unit tests.

FIRST: Properties of Good Tests

Before We Begin

JUnit Test Foundations

Digging Deeper into JUnit Assertions

Organizing Your Tests

Mastering Manic Mnemonics!

What to Test: The Right-BICEP

Boundary Conditions: The CORRECT Way

The Bigger Design Picture

Bigger Design Issues

Using Mock Objects

Refactoring Tests

The Bigger Unit-Testing Picture

Testing Some Tough Stuff

Testing on a Project

Wrapping Up

Appendix - Setting up JUnit

FIRST: Properties of Good Tests

FIRST principle