Introduction to Junit5

 JUnit5 is the next generation of JUnit. The goal is to create an up-to-date foundation for developer-side testing on the JVM. This includes focusing on Java 8 and above, as well as enabling many different styles of testing.

JUnit 5 is split into three sub-projects: Jupiter, Vintage, and Platform.

They communicate via published APIs, which allows tools and libraries to inject customized behavior. Then, each sub-project is split into several artifacts to separate concerns and guarantee maintainability.

JUnit Vintage:

Implements an engine that allows to run tests written in JUnit 3 and 4 with JUnit 5.

JUnit Jupiter is the combination of the new programming model and extension model for writing tests and extensions in JUnit 5. 

Required Dependencies:

The junit-jupiter-api (version 5.4.2):This dependency provides the public API for writing tests and extensions.

The junit-jupiter-engine (version 5.4.2):This dependency contains the implementation of the JUnit Jupiter test engine that runs our unit tests.

Configuring the Maven Surefire Plugin:

build>

    <plugins>

        <plugin>

            <groupId>org.apache.maven.plugins</groupId>

            <artifactId>maven-surefire-plugin</artifactId>

            <version>2.22.1</version>

        </plugin>

    </plugins>

</build>            

Note: First, if we want to use the native JUnit 5 support of the Maven Surefire Plugin, we must ensure that at least one test engine implementation is found from the classpath. 

That’s why we added the junit-jupiter-engine dependency to the test scope.