Tag Archives: JUnit5

JUnit 5 assert log entries in a SpringBoot application

Asserting log entries in JUnit Jupiter is not as straight forward as one might want, but after some digging I found a way that worked for me. It should also me said that doing this i Jupiter is far easier than in previous versions of JUnit

The trick here is to use the SpringBoot OutputCaptureExtension on you test class. This can be accomplished with the @ExtendWith annotation in SpringBoot. This will inject a CapturedOutput object with output from our application

Example test class:

import org.springframework.boot.test.system.CapturedOutput;
import org.springframework.boot.test.system.OutputCaptureExtension;

import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.CoreMatchers.containsString;

public void testHappyCaseSendDataToSystem(CapturedOutput output) throws Exception {

  MockEndpoint mock = camelContext.getEndpoint("mock:senddataToSystem", MockEndpoint.class);

  // Setting expectations

  // Invoking consumer
  producerTemplate.sendBody("direct:start", null);

  // Asserting mock is satisfied

  // Assert log message
  assertThat(output.getOut(), containsString("LogMessage=Completed"));

Tested on SpringBoot v3.2.0 and JUnit 5.10.1

Spring Boot: Create a “RunAllTests” test class with JUnit 5

I like having an easy way to run all tests in a specific package path. I will here show an example of how to create a “RunAllTests” class to use in Spring Boot 2 and JUnit 5 (Jupiter):

package com.niklasottosson.myapp;

import org.junit.platform.runner.JUnitPlatform;
import org.junit.platform.suite.api.SelectPackages;
import org.junit.runner.RunWith;

 * Test class to run all unit tests.
public class RunAllTests {

This will tell JUnit to search the files in the package described (and below) in the @SelectPackages annotation for tests to run

For Spring Boot 2.3.8 the normal “spring-boot-starter-test” dependency was not enough to get the JUnitPlatform into my app (for the @RunWith annotation), so I had to add the following dependency to my pom.xml:


After all is in place I can run the RunAllUnitTests class and all selected tests runs

Tested on Spring Boot v2.3.8, IntelliJ v2020.3 and JUnit v5 with JUnitPlattform v1.2.0