JUnit 5 @AfterEach annotation example

JUnit 5 @AfterEach annotation is replacement of @After annotation in JUnit 4. It is used to signal that the annotated method should be executed after each @Test method in the current class.

@AfterEach Annotation Usage

Annotate a method with @AfterEach as given below:

@AfterEach
public void cleanUpEach(){
	System.out.println("After Each cleanUpEach() method called");
}

@AfterEach annotated method MUST NOT be a static method otherwise it will throw runtime error.

org.junit.platform.commons.JUnitException: @AfterEach method 'public static void com.howtodoinjava.junit5.examples.JUnit5AnnotationsExample.cleanUpEach()' must not be static.
	at org.junit.jupiter.engine.descriptor.LifecycleMethodUtils.assertNonStatic(LifecycleMethodUtils.java:73)
	at org.junit.jupiter.engine.descriptor.LifecycleMethodUtils.lambda$findAfterEachMethods$3(LifecycleMethodUtils.java:60)
	at java.util.ArrayList.forEach(ArrayList.java:1249)
	at java.util.Collections$UnmodifiableCollection.forEach(Collections.java:1080)
	at org.junit.jupiter.engine.descriptor.LifecycleMethodUtils.findAfterEachMethods(LifecycleMethodUtils.java:60)

@AfterEach Annotation Example

Let’s take an example. I have used one Calculator class and added one add method. I will test it 5 times using @RepeatedTest annotation. This annotation will cause the add test to run 5 times. For every run of test method, @AfterEach annotated method should also run every time.

package com.howtodoinjava.junit5.examples;

import org.junit.jupiter.api.AfterAll;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.RepeatedTest;
import org.junit.jupiter.api.RepetitionInfo;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.TestInfo;
import org.junit.platform.runner.JUnitPlatform;
import org.junit.runner.RunWith;

@RunWith(JUnitPlatform.class)
public class AfterAnnotationsTest {

	@DisplayName("Add operation test")
	@RepeatedTest(5)
	void addNumber(TestInfo testInfo, RepetitionInfo repetitionInfo) 
	{
		System.out.println("Running test -> " + repetitionInfo.getCurrentRepetition());
		Assertions.assertEquals(2, Calculator.add(1, 1), "1 + 1 should equal 2");
	}
	
	@AfterAll
	public static void cleanUp(){
		System.out.println("After All cleanUp() method called");
	}
	
	@AfterEach
	public void cleanUpEach(){
		System.out.println("After Each cleanUpEach() method called");
	}
}

Where Calculator class is:

package com.howtodoinjava.junit5.examples;

public class Calculator 
{
	public int add(int a, int b) {
		return a + b;
	}
}

Now execute the test and you will see below console output:

Running test -> 1
After Each cleanUpEach() method called

Running test -> 2
After Each cleanUpEach() method called

Running test -> 3
After Each cleanUpEach() method called

Running test -> 4
After Each cleanUpEach() method called

Running test -> 5
After Each cleanUpEach() method called

After All cleanUp() method called

Clearly, @AfterEach annotated cleanUpEach() method is called once per test method invocation.

Happy Learning !!