@EnabledOnJre for JRE-specific tests in JUnit - Test Execution Trace

Test Overview

This test checks if a method runs only on a specific Java Runtime Environment (JRE) version using the @EnabledOnJre annotation. It verifies that the test executes only when the JRE matches the specified version.

Test Code - JUnit 5

JUnit

import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.condition.EnabledOnJre;
import org.junit.jupiter.api.condition.JRE;
import static org.junit.jupiter.api.Assertions.assertTrue;

public class JreSpecificTest {

    @Test
    @EnabledOnJre(JRE.JAVA_17)
    void testRunsOnlyOnJava17() {
        String version = System.getProperty("java.version");
        assertTrue(version.startsWith("17"), "Test should run only on Java 17");
    }
}

Execution Trace - 5 Steps

Step	Action	System State	Assertion	Result
1	Test runner starts and detects the test method annotated with @EnabledOnJre(JRE.JAVA_17)	JUnit test environment initialized, Java version detected from system properties	-	PASS
2	JUnit checks current JRE version; if it is Java 17, proceeds to run the test method	Running on Java 17 environment	-	PASS
3	Test method executes and retrieves the Java version string from system properties	Inside test method, Java version string obtained	-	PASS
4	Assertion checks if the Java version string starts with "17"	Java version string is "17.x.x"	assertTrue(version.startsWith("17"))	PASS
5	Test completes successfully because the assertion passed	Test method finished without exceptions	-	PASS

Failure Scenario

Failing Condition: The test runs on a JRE version other than Java 17

Execution Trace Quiz - 3 Questions

What does the @EnabledOnJre(JRE.JAVA_17) annotation do in this test?

A Runs the test only if the JRE is Java 17

B Runs the test on all JRE versions except Java 17

C Disables the test permanently

D Runs the test only on Java 8

Key Result

Use @EnabledOnJre to run tests only on specific Java versions, ensuring compatibility and avoiding false failures on unsupported JREs.