In JUnit, a test class can extend a superclass containing reusable test methods. This allows you to share common test logic across multiple test classes without duplication.
Lifecycle, methods @BeforeAll, @AfterAll, @BeforeEach, and @AfterEach can be defined in superclass, allowing shared setup and teardown logic.
Example
package com.logicbig.example;
import org.junit.jupiter.api.BeforeAll;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import static org.junit.jupiter.api.Assertions.assertTrue;
class BaseTest {
@BeforeAll
static void beforeAll() {
System.out.println("before all");
}
@BeforeEach
void beforeEach() {
System.out.println("before each");
}
@Test
void baseTestMethod() {
assertTrue(1 + 1 == 2);
}
}
package com.logicbig.example;
import org.junit.jupiter.api.Test;
import static org.junit.jupiter.api.Assertions.assertTrue;
class SubclassTest extends BaseTest {
@Test
void subTestMethod(){
assertTrue(true);
}
}
Output$ mvn test -Dtest=SubclassTest [INFO] Scanning for projects... [INFO] [INFO] -----------< com.logicbig.example:junit-5-superclass-reuse >------------ [INFO] Building junit-5-superclass-reuse 1.0-SNAPSHOT [INFO] from pom.xml [INFO] --------------------------------[ jar ]--------------------------------- [INFO] [INFO] --- resources:3.3.1:resources (default-resources) @ junit-5-superclass-reuse --- [WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent! [INFO] skip non existing resourceDirectory D:\example-projects\junit-5\junit-5-reuse-tests\junit-5-superclass-reuse\src\main\resources [INFO] [INFO] --- compiler:3.11.0:compile (default-compile) @ junit-5-superclass-reuse --- [INFO] No sources to compile [INFO] [INFO] --- resources:3.3.1:testResources (default-testResources) @ junit-5-superclass-reuse --- [WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent! [INFO] skip non existing resourceDirectory D:\example-projects\junit-5\junit-5-reuse-tests\junit-5-superclass-reuse\src\test\resources [INFO] [INFO] --- compiler:3.11.0:testCompile (default-testCompile) @ junit-5-superclass-reuse --- [INFO] Nothing to compile - all classes are up to date [INFO] [INFO] --- surefire:3.5.0:test (default-test) @ junit-5-superclass-reuse --- [INFO] Using auto detected provider org.apache.maven.surefire.junitplatform.JUnitPlatformProvider [INFO] [INFO] ------------------------------------------------------- [INFO] T E S T S [INFO] ------------------------------------------------------- before all before each before each [INFO] +--com.logicbig.example.SubclassTest - 0.224 ss [INFO] | +-- [OK] baseTestMethod - 0.058 ss [INFO] | '-- [OK] subTestMethod - 0.002 ss [INFO] [INFO] Results: [INFO] [INFO] Tests run: 2, Failures: 0, Errors: 0, Skipped: 0 [INFO] [INFO] ------------------------------------------------------------------------ [INFO] BUILD SUCCESS [INFO] ------------------------------------------------------------------------ [INFO] Total time: 3.497 s [INFO] Finished at: 2025-12-21T08:57:32+08:00 [INFO] ------------------------------------------------------------------------
The SubclassTest inherits tests from BaseTest. When executed, all @Test methods defined in the superclass and subclass are executed as part of the subclass, demonstrating test reuse.
Example ProjectDependencies and Technologies Used: - junit-jupiter-engine 6.0.1 (Module "junit-jupiter-engine" of JUnit)
Version Compatibility: 5.0.0 - 6.0.1 Version compatibilities of junit-jupiter-engine with this example:
- 5.0.0
- 5.0.1
- 5.0.2
- 5.0.3
- 5.1.0
- 5.1.1
- 5.2.0
- 5.3.0
- 5.3.1
- 5.3.2
- 5.4.0
- 5.4.1
- 5.4.2
- 5.5.0
- 5.5.1
- 5.5.2
- 5.6.0
- 5.6.1
- 5.6.2
- 5.6.3
- 5.7.0
- 5.7.1
- 5.7.2
- 5.8.0
- 5.8.1
- 5.8.2
- 5.9.0
- 5.9.1
- 5.9.2
- 5.9.3
- 5.10.0
- 5.10.1
- 5.10.2
- 5.10.3
- 5.10.4
- 5.10.5
- 5.11.0
- 5.11.1
- 5.11.2
- 5.11.3
- 5.11.4
- 5.12.0
- 5.12.1
- 5.12.2
- 5.13.0
- 5.13.1
- 5.13.2
- 5.13.3
- 5.13.4
- 5.14.0
- 5.14.1
- 6.0.0
- 6.0.1
Versions in green have been tested.
- JDK 25
- Maven 3.9.11
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