In JUnit 4, test classes and methods were typically required to be public.
In JUnit 5, Test classes, test methods, and lifecycle methods are not required to be public, but they must not be private.
They can be protected or package-private (i.e. no access modifier). It was probably done so that we don't need to explicitly declare everything as public. Secondly, package-private access provides better encapsulation, which prevents accidental external usage of test methods.

Example

A class to be tested

desc

package com.logicbig.example;

public class Calc {
  public int multiply(int a, int b) {
      return a * b;
  }
}

CalcTest

Here we can use no access modifier (package-private) on @Test and lifecycle methods.

package com.logicbig.example;

import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;

class CalcTest {

  Calc calc;

  @BeforeEach
  void eachInit() {
      calc = new Calc();
  }

  @Test
  void testMultiply() {
      int actual = calc.multiply(3, 5);
      Assertions.assertEquals(15, actual);
  }
}

mvn test -Dtest=CalcTest

Output

D:\example-projects\junit-5\junit-5-access-modifier>mvn test -Dtest=CalcTest
[INFO] Scanning for projects...
[INFO] 
[INFO] ------------< com.logicbig.example:junit-5-getting-started >------------
[INFO] Building junit-5-getting-started 1.0-SNAPSHOT
[INFO]   from pom.xml
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] 
[INFO] --- resources:3.3.1:resources (default-resources) @ junit-5-getting-started ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory D:\example-projects\junit-5\junit-5-getting-started\src\main\resources
[INFO] 
[INFO] --- compiler:3.14.1:compile (default-compile) @ junit-5-getting-started ---
[INFO] Nothing to compile - all classes are up to date.
[INFO] 
[INFO] --- resources:3.3.1:testResources (default-testResources) @ junit-5-getting-started ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory D:\example-projects\junit-5\junit-5-getting-started\src\test\resources
[INFO] 
[INFO] --- compiler:3.14.1:testCompile (default-testCompile) @ junit-5-getting-started ---
[INFO] Recompiling the module because of changed source code.
[INFO] Compiling 1 source file with javac [debug target 25] to target\test-classes
[INFO] 
[INFO] --- surefire:3.2.5:test (default-test) @ junit-5-getting-started ---
[INFO] Using auto detected provider org.apache.maven.surefire.junitplatform.JUnitPlatformProvider
[INFO] 
[INFO] -------------------------------------------------------
[INFO]  T E S T S
[INFO] -------------------------------------------------------
[INFO] Running com.logicbig.example.CalcTest
[INFO] Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.054 s -- in com.logicbig.example.CalcTest
[INFO] 
[INFO] Results:
[INFO] 
[INFO] Tests run: 1, Failures: 0, Errors: 0, Skipped: 0
[INFO] 
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  3.258 s
[INFO] Finished at: 2025-11-30T08:59:54+08:00
[INFO] ------------------------------------------------------------------------

Example Project

Dependencies and Technologies Used:

• junit-jupiter-engine 6.0.1 (Module "junit-jupiter-engine" of JUnit)
   Version Compatibility: 5.0.0 - 6.0.1Version List
  ×

  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