You can open this sample inside an IDE using the IntelliJ native importer or Eclipse Buildship.

This sample shows how to test Java projects with JUnit4 in Gradle.

For applications:

application/build.gradle
plugins {
    id 'application'
}

dependencies {
    implementation project(':list')
    implementation project(':utilities')
    testImplementation 'junit:junit:4.12'
}

application {
    mainClassName = 'org.gradle.sample.Main'
}
application/build.gradle.kts
plugins {
    application
}

dependencies {
    implementation(project(":list"))
    implementation(project(":utilities"))
    testImplementation("junit:junit:4.12")
}

application {
    mainClassName = "org.gradle.sample.Main"
}

For libraries:

list/build.gradle
plugins {
    id 'java-library'
}

dependencies {
    testImplementation 'junit:junit:4.12'
}
list/build.gradle.kts
plugins {
    `java-library`
}

dependencies {
    testImplementation("junit:junit:4.12")
}

Running the tests:

$ ./gradlew test

BUILD SUCCESSFUL
5 actionable tasks: 5 executed

For more information, see Testing in Java project chapter.

You can also generate this project locally using gradle init.