@Disabled for skipping tests in JUnit - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Purpose of @Disabled Annotation in JUnit

What is the primary purpose of the @Disabled annotation in JUnit 5?

A To run a test multiple times automatically

B To mark a test as expected to fail

C To enable parallel execution of tests

D To temporarily skip the execution of a test method or class

💡 Hint

Think about why you might want to prevent a test from running temporarily.

The @Disabled annotation is used to skip a test method or an entire test class temporarily. This is useful when a test is broken or not ready to run but you don't want to delete it.

❓ Predict Output

intermediate

Effect of @Disabled on Test Execution Count

Given the following JUnit 5 test class, how many tests will be executed when running this class?

JUnit

import org.junit.jupiter.api.*;

public class SampleTest {

    @Test
    void testOne() {
        System.out.println("Test One");
    }

    @Disabled
    @Test
    void testTwo() {
        System.out.println("Test Two");
    }

    @Test
    void testThree() {
        System.out.println("Test Three");
    }
}

A 2

B 3

C 1

D 0

💡 Hint

Count only tests that are not disabled.

The test method testTwo is annotated with @Disabled, so it will be skipped. The other two tests will run, so total executed tests are 2.

❓ assertion

advanced

Assertion Behavior in Disabled Tests

Consider a test method annotated with @Disabled that contains failing assertions. What will be the test result when running this test?

A The test will be skipped and no assertion failures reported

B The test will fail due to assertion errors

C The test will pass regardless of assertions

D The test will run but report warnings instead of failures

💡 Hint

Think about whether the test code runs at all when disabled.

When a test is annotated with @Disabled, it is skipped entirely. The test method code, including assertions, is not executed, so no failures or passes are recorded for that test.

🔧 Debug

advanced

Why is a Disabled Test Still Running?

A developer added @Disabled to a test method, but the test still runs during the test suite execution. Which of the following is the most likely cause?

A The test runner does not support <code>@Disabled</code>

B The test method is missing the <code>@Test</code> annotation

C The <code>@Disabled</code> annotation was imported from the wrong package

D The test method is private instead of public

💡 Hint

Check the import statements for annotations.

If @Disabled is imported from a wrong or unrelated package, it will not be recognized by JUnit 5, so the test will run as usual.

❓ framework

expert

Combining @Disabled with Conditional Test Execution

In JUnit 5, if a test method is annotated with both @Disabled and a conditional annotation like @EnabledOnOs(OS.WINDOWS), what will happen when running the tests on a Windows machine?

A JUnit will throw an error due to conflicting annotations

B The test will be skipped because @Disabled takes precedence over conditional annotations

C The test will run because the condition is met, ignoring @Disabled

D The test will run only if both annotations allow it, so it runs on Windows

💡 Hint

Consider the priority of @Disabled in test execution.

The @Disabled annotation always disables the test regardless of other conditional annotations. It has the highest priority and causes the test to be skipped.