@Execution annotation in JUnit - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of the @Execution annotation in JUnit?

The <code>@Execution</code> annotation controls whether tests in a test class or method run concurrently or sequentially in JUnit.

beginner

What are the two modes available with the @Execution annotation?

The two modes are CONCURRENT (tests run in parallel) and SAME_THREAD (tests run sequentially in the same thread).

beginner

How do you apply <code>@Execution</code> to run all tests in a class concurrently?

Add <code>@Execution(ExecutionMode.CONCURRENT)</code> above the test class declaration to run all its tests in parallel.

intermediate

Can @Execution be used on individual test methods?

No, <code>@Execution</code> is only applicable at the class level to control execution mode for all tests in that class.

intermediate

Why might you choose ExecutionMode.SAME_THREAD over CONCURRENT?

Use SAME_THREAD when tests share state or resources that are not thread-safe, to avoid flaky or failing tests.

What does @Execution(ExecutionMode.CONCURRENT) do in JUnit?

A Skips the tests

B Runs tests one after another in the same thread

C Runs tests only once

D Runs tests in parallel threads

The CONCURRENT mode runs tests in parallel threads to speed up execution.

Where can you apply the @Execution annotation?

A On both test classes and methods

B On individual test methods only

C On test classes only

D On test suites only

@Execution is designed to be used on test classes to control execution mode for all tests inside.

Which execution mode should you use if your tests share mutable state?

A SAME_THREAD

B CONCURRENT

C PARALLEL

D ASYNC

SAME_THREAD ensures tests run sequentially to avoid conflicts with shared mutable state.

What is the default execution mode if @Execution is not specified?

A CONCURRENT

B SAME_THREAD

C ASYNC

D PARALLEL

JUnit runs tests sequentially by default, which corresponds to SAME_THREAD mode.

Which import is required to use @Execution in JUnit?

A org.junit.jupiter.api.parallel.Execution

B org.junit.jupiter.api.Test

C org.junit.jupiter.api.BeforeEach

D org.junit.jupiter.api.Assertions

The @Execution annotation is in the org.junit.jupiter.api.parallel package.

Explain how the @Execution annotation affects test execution in JUnit.

Think about running tests at the same time versus one by one.

Describe a scenario where you would prefer ExecutionMode.SAME_THREAD over CONCURRENT.

Consider tests that might interfere with each other if run at the same time.