When to use this skill Use this skill whenever the user wants to: - Write Java or Kotlin unit tests with JUnit 4 or JUnit 5 (Jupiter) - Use annotations (@Test, @BeforeEach, @AfterEach, @ParameterizedTest) - Apply assertions (assertEquals, assertThrows, assertAll) - Integrate with Mockito or AssertJ for mocking and fluent assertions - Configure test execution with Maven Surefire or Gradle How to use this skill Workflow 1. Write test classes and methods annotated with 2. Set up and tear down test state with lifecycle annotations 3. Use assertions to verify expected behavior 4. Mock dependencies…