59 JUnit Interview Questions and Answers for 2026

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These 21 questions cover the vocabulary and annotations you are expected to know before writing your first production test. If you are new to the framework, work through the JUnit tutorial alongside this section.

1. What Is JUnit?

JUnit is an open-source unit-testing framework for the Java programming language. It provides annotations to mark test methods and lifecycle hooks, assertions to verify expected behaviour, and test runners that execute those tests and report results. It is the de facto standard for developer-side testing on the JVM and integrates with Maven, Gradle, and every major Java IDE.

2. Why Is Unit Testing Important?

Unit tests verify the smallest testable pieces of code in isolation, which means a failure points at one method rather than a whole feature. They catch regressions at the moment a change is made rather than in QA, they document intended behaviour in executable form, and they make refactoring safe because the suite tells you immediately when behaviour changed.

3. What Is the Current Version of JUnit?

JUnit 6 is the current generation. JUnit 6.0.0 was released on September 30, 2025, and the line has continued with patch and minor releases since. JUnit 6 requires Java 17 or later and Kotlin 2.1 or later, which is the single most important upgrade constraint. JUnit 5 remains extremely common in existing codebases, and JUnit 4 is still found in legacy projects.

4. What Are the Three Modules of JUnit 5 and JUnit 6?

Modern JUnit is not a single library. It is composed of three sub-projects:

• JUnit Platform - the foundation that launches testing frameworks on the JVM. It defines the TestEngine API and provides the console launcher plus the Maven and Gradle integrations.
• JUnit Jupiter - the new programming model and extension model. This is where @Test, @BeforeEach, assertions, and @ExtendWith live.
• JUnit Vintage - a TestEngine that runs JUnit 3 and JUnit 4 tests on the Platform, which is what makes gradual migration possible.

Naming these three, and saying which one your annotations come from, is one of the fastest ways to show you understand the architecture rather than just the syntax.

5. What Does the @Test Annotation Do?

@Test marks a method as a test method so the engine discovers and executes it. In Jupiter the method must not be private and must not be static, and it returns void. Unlike JUnit 4, the Jupiter @Test annotation takes no attributes, so expected exceptions and timeouts moved to assertThrows() and @Timeout respectively.

import org.junit.jupiter.api.Test;
import static org.junit.jupiter.api.Assertions.assertEquals;

class CalculatorTest {

    @Test
    void addsTwoNumbers() {
        assertEquals(4, new Calculator().add(2, 2));
    }
}

6. What Are @BeforeEach and @AfterEach?

@BeforeEach runs before every test method in the class and @AfterEach runs after every test method. They are used to build a fresh fixture per test and to release resources afterwards, which is what keeps tests isolated from one another. In JUnit 4 these were @Before and @After.

7. What Are @BeforeAll and @AfterAll?

@BeforeAll runs once before all tests in the class and @AfterAll runs once after all of them. By default they must be static, because the default lifecycle creates a new test instance per method. They suit expensive one-time setup such as starting a container or opening a connection pool. In JUnit 4 these were @BeforeClass and @AfterClass.

8. What Is the Difference Between @BeforeEach and @BeforeAll?

Frequency and scope. @BeforeEach executes once per test method and is the right place for state that must not leak between tests. @BeforeAll executes once per test class and is the right place for setup too costly to repeat. The practical rule: if two tests could interfere through the object you are creating, create it in @BeforeEach.

9. What Is an Assertion in JUnit?

An assertion is a static method that checks a condition and fails the test by throwing an AssertionError when the condition does not hold. Assertions are what turn a method that merely runs into a method that verifies. In Jupiter they live in org.junit.jupiter.api.Assertions. See our worked examples of JUnit assertions for the full set in context.

10. Which Assertion Methods Are Most Commonly Used?

• assertEquals(expected, actual) - checks equality using equals(). The expected value comes first, which trips people up in failure messages.
• assertTrue and assertFalse - check a boolean condition.
• assertNull and assertNotNull - check reference nullity.
• assertThrows - asserts that a block throws a given exception type and returns the exception for further inspection.
• assertAll - groups assertions so all of them run and every failure is reported together.
• assertSame and assertNotSame - check reference identity rather than equality.

11. What Is the Difference Between assertEquals and assertSame?

assertEquals compares using the equals() method, so two distinct objects with equal contents pass. assertSame compares references with ==, so it passes only when both arguments are the same object on the heap. Reach for assertSame when identity genuinely matters, such as verifying a cache returned the cached instance rather than a copy.

12. What Does @DisplayName Do?

@DisplayName sets a custom, human-readable name for a test class or method, including spaces, special characters, and emoji. It is reported by IDEs and build tools instead of the method name, which makes failure output readable by people who did not write the test.

13. What Is @Disabled and How Does It Differ From @Ignore?

@Disabled skips a test class or method, and it accepts an optional reason string that gets reported. It is the Jupiter replacement for JUnit 4's @Ignore. Treat a disabled test as debt with an expiry date, not a way to make the build green. Our post on the JUnit Ignore test annotation covers the JUnit 4 behaviour and the migration.

14. How Do You Test for Exceptions in JUnit 5?

You use the assertThrows() assertion, which verifies that a specified exception type is thrown when a piece of code executes and returns the exception instance for further assertions. This is a real improvement on JUnit 4's @Test(expected = ...) because it scopes the expectation to a specific statement rather than the whole method, and it lets you assert on the message.

@Test
void rejectsDivisionByZero() {
    ArithmeticException ex = assertThrows(
        ArithmeticException.class,
        () -> new Calculator().divide(0)
    );
    assertEquals("/ by zero", ex.getMessage());
}

15. What Is a Test Fixture?

A test fixture is the fixed state a test runs against: the objects, data, and resources prepared before the test and cleaned up afterwards. In JUnit the fixture is built by lifecycle methods annotated with @BeforeEach, @BeforeAll, @AfterEach, and @AfterAll. A good fixture makes each test start from an identical, predictable environment.

16. How Do JUnit 4 Annotations Map to JUnit 5?

17. What Is the JUnit Test Lifecycle?

For a single test class the order is: @BeforeAll runs once, then for each test method a new test instance is created, @BeforeEach runs, the @Test method runs, @AfterEach runs, and finally @AfterAll runs once after all methods complete. Understanding that a fresh instance is created per method explains why instance fields do not leak between tests and why @BeforeAll must be static.

18. How Do You Run JUnit Tests?

Four common routes: from an IDE such as IntelliJ IDEA or Eclipse, through a build tool with mvn test or gradle test, from the JUnit Platform Console Launcher, or from a CI pipeline that invokes the build tool. Our walkthrough on executing JUnit tests from the command line covers the console launcher options.

19. What Dependency Do You Add to Use JUnit 5 or 6?

The aggregate artifact org.junit.jupiter:junit-jupiter pulls in the API, the params support, and the engine together, which is what most projects want. Add junit-vintage-engine only if you still need to run JUnit 4 tests. Setup details for both build tools are in our guide to setting up the JUnit environment.

<dependency>
    <groupId>org.junit.jupiter</groupId>
    <artifactId>junit-jupiter</artifactId>
    <scope>test</scope>
</dependency>

20. Can a JUnit 5 Test Method Be Private or Static?

No. Jupiter test methods must not be private and must not be static, or the engine will not execute them. They may be package-private, which is why many teams drop the public modifier that JUnit 4 required. Lifecycle methods follow the same rule, with the exception that @BeforeAll and @AfterAll must be static under the default per-method lifecycle.

21. What Is assertAll and Why Use It?

assertAll groups several assertions so that all of them execute even if an early one fails, then reports every failure together in a MultipleFailuresError. With plain sequential assertions the first failure aborts the method and hides the rest, so you fix one problem per run. assertAll gives you the full picture in a single run.

Key Takeaway: Fresher-level JUnit interview questions cover what JUnit is, the @Test annotation, assertions that throw an AssertionError on failure, @Disabled versus @Ignore, the test lifecycle order, and assertAll for grouping several assertions.

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These 21 questions target engineers with a year or two of hands-on testing. They move past annotations into parameterization, the extension model, mocking, and the lifecycle controls that shape how a suite behaves.

22. What Is a Parameterized Test?

A parameterized test runs the same test method multiple times with different arguments, reporting each invocation as a separate test. You annotate the method with @ParameterizedTest instead of @Test and supply a source of arguments. It replaces copy-pasted near-identical tests with one method and a data table. See our worked example of a JUnit parameterized test.

23. Which Argument Sources Can a Parameterized Test Use?

• @ValueSource - a literal array of a single primitive, String, or Class type.
• @CsvSource - inline comma-separated rows, useful for a handful of multi-argument cases.
• @CsvFileSource - the same idea backed by a CSV file on the classpath.
• @MethodSource - a static factory method returning a Stream of arguments, which is the option for complex objects.
• @EnumSource - the constants of an enum, with include and exclude filters.
• @NullSource, @EmptySource, @NullAndEmptySource - the edge cases that get forgotten most often.
• @ArgumentsSource - a custom ArgumentsProvider when none of the built-ins fit.

24. What Is @RepeatedTest Used For?

@RepeatedTest runs the same test a specified number of times, optionally injecting a RepetitionInfo to know which repetition is executing. It is useful for smoking out non-determinism and for exercising code with randomised input. It is not a substitute for fixing a flaky test. Details are in our post on the @RepeatedTest annotation in JUnit 5.

25. What Does @Nested Do?

@Nested marks an inner non-static class as a nested test class, letting you group tests that share a context and express relationships between them. Outer @BeforeEach methods run before inner ones, so you can layer fixtures. It produces readable reports of the form "when the cart is empty, then checkout is rejected". Our guide covers JUnit 5 nested tests in depth.

26. What Is @Tag and How Is It Used?

@Tag attaches a label to a test class or method so suites can be filtered at run time, for example running only tests tagged "smoke" in a pull-request pipeline and the full set nightly. Build tools expose include and exclude tag expressions, which support and, or, and not. It is the Jupiter replacement for JUnit 4's @Category.

27. What Are Dynamic Tests and @TestFactory?

A @TestFactory method returns a collection or stream of DynamicTest instances generated at run time rather than declared at compile time. Where @ParameterizedTest binds known data to a fixed method, dynamic tests let the number and shape of tests be decided while the suite runs, for example one test per file discovered in a directory. Their lifecycle differs: @BeforeEach does not run for each dynamic test.

28. What Can Be Injected Into a Test Method?

Jupiter resolves method and constructor parameters through the ParameterResolver extension API. Built-in resolvers supply TestInfo for metadata about the current test, TestReporter for publishing key-value entries into the report, and RepetitionInfo inside a @RepeatedTest. Custom resolvers can inject anything, which is how frameworks like Spring inject beans into tests.

29. What Does @TestInstance Control?

@TestInstance sets the test instance lifecycle. The default, PER_METHOD, creates a new instance of the test class for every test method, which is what guarantees isolation. PER_CLASS reuses one instance across all methods, which lets @BeforeAll be non-static and allows @MethodSource factories to be instance methods, at the cost of shared mutable state you must manage yourself.

30. What Is the JUnit 5 Extension Model?

Extensions are the single, unified way to hook into the test lifecycle, replacing JUnit 4's runners, rules, and class rules. You register one with @ExtendWith on a class or method, or with @RegisterExtension on a field when you need programmatic control. Unlike @RunWith, which allowed exactly one runner, multiple extensions compose freely. See JUnit 5 features and extensions.

31. Which Extension Points Are Available?

• Lifecycle callbacks - BeforeAllCallback, BeforeEachCallback, AfterEachCallback, and AfterAllCallback wrap the standard hooks.
• TestExecutionExceptionHandler - intercepts exceptions thrown by a test so you can swallow, translate, or rethrow them.
• ParameterResolver - supplies arguments for test constructors and methods.
• ExecutionCondition - decides whether a container or test runs at all, which is how the conditional annotations are implemented.
• TestInstancePostProcessor - operates on a freshly created test instance, commonly used to inject mocks.

32. What Is the Difference Between an Assumption and an Assertion?

An assertion that fails marks the test as failed. An assumption that fails aborts the test and marks it as skipped, not failed. Use assumeTrue() or assumingThat() when a test is only meaningful in certain environments, for example a test that needs a specific operating system or an integration endpoint that is not always reachable.

33. How Do You Run a Test Conditionally?

Jupiter ships declarative conditions built on ExecutionCondition: @EnabledOnOs and @DisabledOnOs for the operating system, @EnabledOnJre and @EnabledForJreRange for the Java version, @EnabledIfSystemProperty and @EnabledIfEnvironmentVariable for configuration, and @EnabledIf for a custom boolean method. They express intent more clearly than an if-statement plus an early return, which would report a false pass.

34. What Does @Timeout Do?

@Timeout fails a test if it runs longer than the given duration, and it can be applied to methods, classes, or lifecycle methods. It replaces JUnit 4's @Test(timeout = ...) attribute. There are also assertTimeout and assertTimeoutPreemptively assertions when you want to bound a specific block rather than the whole method.

35. Can You Control the Order Tests Run In?

Yes, with @TestMethodOrder and a MethodOrderer such as OrderAnnotation, which reads @Order values, plus DisplayName and MethodName orderers. The honest interview answer is that needing a specific order is usually a design smell: tests that depend on their predecessors are not isolated. Order is legitimate for reporting readability or genuinely sequential integration scenarios.

36. How Do You Enable Parallel Test Execution?

Parallelism is configuration-driven. Set junit.jupiter.execution.parallel.enabled to true in junit-platform.properties, choose a parallelism strategy, and use @Execution to mark classes or methods as CONCURRENT or SAME_THREAD. Shared mutable state is the failure mode, and @ResourceLock is the tool for declaring that two tests contend for the same resource. Our guide covers parallel testing with JUnit 5.

37. What Is Mockito and Why Is It Used With JUnit?

JUnit runs tests; Mockito creates test doubles. A unit test should exercise one class in isolation, so collaborators like repositories and HTTP clients are replaced with mocks whose behaviour you stub and whose interactions you verify. The two are complementary rather than competing, and the pairing is close to standard on Java projects. See our JUnit 5 and Mockito tutorial.

38. What Is the Difference Between @Mock and @InjectMocks?

@Mock creates a mock instance of a dependency. @InjectMocks creates a real instance of the class under test and injects the declared mocks into it, through the constructor where possible and otherwise by setter or field. The class under test gets @InjectMocks; everything it depends on gets @Mock.

39. How Do You Activate Mockito Annotations in JUnit 5?

Register MockitoExtension with @ExtendWith(MockitoExtension.class) from the mockito-junit-jupiter artifact. It initialises annotated mocks before each test and validates that stubbings were used, which surfaces dead stubs. The alternative is calling MockitoAnnotations.openMocks(this) in a @BeforeEach method.

40. How Does Exception Testing Differ Between JUnit 4 and JUnit 5?

JUnit 4 used @Test(expected = SomeException.class), which passed if the exception was thrown anywhere in the method, including from setup code that was never meant to throw. JUnit 5's assertThrows scopes the expectation to one lambda and returns the exception object, so you can assert on its message, cause, and fields. The JUnit 4 form is strictly less precise.

41. How Do You Test a Private Method?

Usually you do not test it directly. Private methods are implementation detail, so exercise them through the public API that calls them; if that is impractical, the private method is often doing enough work to deserve its own class. Reflection or visibility relaxation are last resorts that couple the test to internals and make refactoring harder.

42. How Is Code Coverage Measured for JUnit Tests?

JaCoCo is the common choice on the JVM. It instruments bytecode during the test run and reports line, branch, and instruction coverage, and it can fail a build below a configured threshold. The caveat worth voicing in an interview: coverage measures which lines executed, not whether the assertions were meaningful, so a high number with weak assertions proves very little.

Key Takeaway: Intermediate-level JUnit interview questions cover parameterized tests that report each invocation separately, @Tag for filtering suites such as smoke tests, the extension model, @Timeout, @Mock versus @InjectMocks, and code coverage with JaCoCo.

These 15 questions are the ones that separate someone who uses JUnit from someone who can own a test suite. They cover architecture, migration, flakiness, and execution at scale.

43. How Does the JUnit Platform Discover and Execute Tests?

The Platform defines a TestEngine SPI. A Launcher builds a discovery request from selectors and filters, asks every registered engine to discover matching tests, and receives back a TestDescriptor tree. It then executes that plan and streams events to registered listeners, which is how IDEs and build tools display live results. Jupiter and Vintage are simply two engines implementing that SPI, which is why third parties can plug their own frameworks into the same tooling.

44. What Changed in JUnit 6?

JUnit 6.0.0 arrived on September 30, 2025 as a coordinated release of Platform, Jupiter, and Vintage. The headline changes are a raised baseline of Java 17 and Kotlin 2.1, unified versioning so all modules share one version number instead of the old three-track scheme, and the removal of APIs deprecated across the JUnit 5 line. The Jupiter programming model is deliberately stable, so most test code compiles unchanged.

45. How Would You Migrate a JUnit 4 Suite to JUnit 5 or 6?

Incrementally, using the Vintage engine. Add the Jupiter dependencies alongside junit-vintage-engine so existing JUnit 4 tests keep running unchanged, then write all new tests in Jupiter and convert old ones opportunistically. Rules are the hard part, since they have no direct equivalent and must be reimplemented as extensions. Drop Vintage once the last JUnit 4 test is gone. Our guides on executing JUnit 4 tests with JUnit 5 and the JUnit 6 migration path cover both hops.

46. How Do You Write a Custom Extension?

Implement one or more extension interfaces and register the class with @ExtendWith. A database extension might implement BeforeAllCallback to start a container, ParameterResolver to hand tests a connection, and AfterAllCallback to tear it down. Use the ExtensionContext Store to keep state, scoped to the right lifecycle level, rather than static fields that leak across classes.

47. When Would You Use @RegisterExtension Instead of @ExtendWith?

@ExtendWith is declarative and takes a class, so the extension is constructed by the framework with no arguments. @RegisterExtension applies to a field holding an instance you created yourself, which is what you need when the extension requires constructor arguments or when you want to query it from the test. Declare the field static to bind the extension at class level.

48. What Causes Flaky Tests and How Do You Handle Them?

• Shared mutable state - order-dependent tests that pass alone and fail in a suite. Fix by rebuilding the fixture per test.
• Timing and concurrency - fixed sleeps standing in for synchronisation. Replace with polling on a real condition.
• External dependencies - live networks and third-party services. Replace with mocks or contained instances.
• Environment assumptions - locale, timezone, and file separators. Pin them explicitly rather than inheriting from the machine.

Blanket automatic retries hide the defect and let it reach production. Quarantine the test, find the root cause, then fix it.

49. How Do You Keep Tests Isolated?

Rely on the default PER_METHOD lifecycle so each test gets a fresh instance, build state in @BeforeEach rather than static fields, avoid singletons and mutable statics in the code under test, and reset anything genuinely global in @AfterEach. A practical check is to run the suite in a randomised order; if results change, isolation is broken somewhere.

50. What Are the Risks of Parallel Execution and How Do You Manage Them?

Parallelism turns latent isolation bugs into intermittent failures, because tests that quietly shared a static field or a temp file now collide. Manage it by declaring contention explicitly with @ResourceLock, pinning genuinely unsafe tests with @Execution(SAME_THREAD), and keeping the parallelism strategy in configuration so it can be tuned per environment rather than hardcoded.

51. How Do You Test Asynchronous Code?

Make the asynchronous boundary controllable. Inject the executor so the test can supply a synchronous one, join on the returned CompletableFuture, or poll a condition with a timeout rather than sleeping a fixed interval. Bound the whole thing with @Timeout so a hung test fails fast instead of stalling the pipeline. A raw Thread.sleep is the pattern that produces flaky suites.

52. How Do JUnit Tests Fit Into a CI/CD Pipeline?

The build tool runs the suite on every push and fails the pipeline on any failure. Tag-based filtering keeps pull-request feedback fast by running a smoke subset, with the full suite on merge or nightly. The Platform emits standard XML reports that CI servers parse for trend and flakiness reporting, and coverage gates can block a merge that drops below threshold.

53. What Is the Difference Between JUnit and TestNG?

Both run Java tests, but they differ in emphasis. TestNG was built with suite configuration, test dependencies, and flexible grouping in mind, driven by XML suite files. JUnit focuses on the unit-test model with an extension system rather than built-in dependency management, and it is the default in most Java build tooling. Modern JUnit has closed much of the historical feature gap through parameterized tests, tags, and parallel execution. Our JUnit 5 vs TestNG comparison goes feature by feature.

54. What Makes a Good Unit Test?

• One reason to fail - a focused test names the defect in its failure message.
• Independent of other tests - it passes alone, in a suite, and in random order.
• Fast - milliseconds, so developers actually run the suite before pushing.
• Deterministic - same input, same result, on every machine and every run.
• Readable as specification - the name and body explain intended behaviour without a debugger.

55. What Are Common JUnit Anti-Patterns?

Tests with no assertions that pass as long as nothing throws; assertions on implementation detail so every refactor breaks the suite; over-mocking to the point that the test verifies the mock rather than the code; @Disabled used indefinitely to keep a build green; and a single test method asserting a dozen unrelated behaviours, which reports one failure and hides the rest.

56. How Do You Speed Up a Slow JUnit Suite?

First separate genuine unit tests from integration tests with @Tag, since a suite is usually slow because a minority of tests touch a database or network. Then enable parallel execution, replace live dependencies with mocks or shared contained instances, and move expensive setup into @BeforeAll. Measure before and after rather than guessing which tests dominate.

57. How Do You Run Large JUnit Suites at Scale?

Once a suite outgrows one machine, the constraint becomes distribution rather than the framework. HyperExecute is TestMu AI's test orchestration cloud, built to run suites up to 70% faster than a traditional hub-and-node grid by keeping the test script and its execution components in a single isolated environment instead of paying network hops between them. It splits a suite across just-in-time virtual machines using Matrix, Auto-Split, or Hybrid strategies, tears each machine down after the run so no state leaks between jobs, and returns unified logs, reports, and AI root cause analysis for failures. For browser-facing JUnit and Selenium tests, the same run can fan out across 3,000+ browser and OS combinations. The HyperExecute getting started documentation covers the YAML setup.

Key Takeaway: Experienced-level JUnit interview questions cover test discovery through the TestEngine SPI, custom extensions, test isolation, tag-based filtering in CI/CD pipelines, anti-patterns such as tests without assertions, and scaling test execution.

Unit tests are the code that AI coding assistants write most often, and an AI agent can run the build, read the failures, and change the code in a loop. These two questions check whether a candidate can keep a JUnit suite meaningful when part of it is generated.

58. What Do You Check in JUnit Tests That an AI Assistant or Agent Generated?

• Mixed generations - JUnit 4 imports such as org.junit.Test, @Before, @RunWith, or @Rule inside a Jupiter project. The test compiles when the Vintage engine is present and silently does not run when it is not.
• Assertions that mirror the code - expected values copied from the current output, which confirm a bug as correct behaviour. Compare each assertion with the requirement.
• Tests that cannot fail - no assertion at all, assertions on a mock the test configured itself, or an exception swallowed in a try-catch block. Mutation testing with PIT exposes them, because the mutants survive.
• Over-mocking - every collaborator mocked, including value objects, so the test verifies only the wiring. Strict stubs in MockitoExtension flag the unused stubbings this produces.
• Swapped arguments - assertEquals(actual, expected), which passes and fails identically but produces misleading failure messages.
• Hidden time and order dependencies - Thread.sleep, the system clock, and shared static state.

59. What Rules Do You Set Before an AI Agent May Fix Failing JUnit Tests by Itself?

• Diagnose first - the agent states whether the production code or the test is wrong before it edits either one.
• Never weaken a test - deleting assertions, loosening expected values, or adding @Disabled requires an explicit approval.
• Objective gates - the full suite, a JaCoCo coverage threshold, and ideally a PIT mutation score run in CI, so quality is measured rather than claimed.
• Small changes - one class or one failing test per pull request, with the reasoning in the description, because large generated diffs do not get a careful review.
• Reproducible runs - the agent uses the same Maven or Gradle wrapper command as CI, so a local pass means the same thing as a pipeline pass.

Key Takeaway: Generated JUnit tests are reviewed for JUnit 4 imports in a Jupiter project, assertions copied from the implementation, tests that cannot fail, over-mocking, and swapped assertEquals arguments, and an agent that repairs tests may never weaken an assertion or disable a test without approval.

Before your interview, do one concrete thing: open a small project, write a @ParameterizedTest with a @MethodSource, and make it fail on purpose so you can read the failure output. Being able to talk through a real failure message is worth more than reciting annotation names.

Two details carry disproportionate weight in 2026. Know that JUnit 6 is current and that it moves the baseline to Java 17, and be able to explain why the Platform, Jupiter, and Vintage split is what makes gradual migration possible. Both signal that you track the framework rather than having learned it once.

If the role involves owning a suite rather than just writing tests, be ready on flakiness and execution time, since those are the problems teams actually hire for. Work through the JUnit test cases guide for hands-on practice, and see the JUnit annotations tutorial for the full annotation reference.