Gain insights into unit testing with JUnit 5. Learn about assertions, assumptions, nested and parameterized tests, advanced JUnit 5 concepts, and integrating tests with Maven and Gradle.

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junit5.tar.gz

mvn clean test

Unit Testing is a basic and essential skill to learn for any developer. In this course, you will learn what unit tests are, why they are important, and how to test your Java applications using the JUnit 5 Framework —  the most popular unit testing framework in the market for Java developers.

You will start with the fundamentals of Unit Testing and JUnit 5 and then gradually you will dive deep into the core concepts like assertions, assumptions, different types of tests like nested tests, parameterized tests, repeated tests, and more.

You will also learn some advanced concepts of JUnit 5 like the JUnit 5 extension model, dependency injection, how to migrate existing unit tests from JUnit 4 to JUnit 5, and how to integrate your unit tests with Maven and Gradle.

Unit Testing Java Applications using JUnit 5

The `TestInstanceProcessor` extension allows the code to run after an instance of a test is created.

We have to create a class that extends the `TestInstancePostProcesso`r interface. This allows us to write an extension that accesses the test instance post-processor extension point.

## Use case 
A commonly used extension for the test instance post-processor extension point is `MockitoExtension`. It injects mock objects into our unit test.

If we want to use a logger to log the `debug` or `info` statements inside our tests, we create a separate extension to inject the instance of the logger into our tests automatically.

## Example



The `TestInstanceProcessor` extension allows the code to run after an instance of a test is created.

We have to create a class that extends the `TestInstancePostProcesso`r interface. This allows us to write an extension that accesses the test instance post-processor extension point.

# Use case 
A commonly used extension for the test instance post-processor extension point is `MockitoExtension`. It injects mock objects into our unit test.

If we want to use a logger to log the `debug` or `info` statements inside our tests, we create a separate extension to inject the instance of the logger into our tests automatically.

# Example



Learn to use the `TestInstancePostProcessor` extension.

Before We Begin

Introduction to JUnit 5

Junit 5 Core Concepts

Dynamic Tests

Dependency Injection in JUnit 5

JUnit 5 Extensions

Migrating from Junit 4 to Junit 5

Appendix

BONUS: Useful Assertion Libraries

Conclusion

Using the `TestInstancePostProcessor` Extension

Use case

Example