Spring Boot + JUnit 5 + Mockito
In this article, we will show you how to do Spring Boot 2 integration test with JUnit 5, and also Mockito.
- Spring Boot 2.1.2.RELEASE
- JUnit 5
- Mockito 2
- Maven 3
In short, exclude junit4 from spring-boot-starter-test
, and include the JUnit 5 jupiter engine manually, done.
Let see the following Spring boot MVC web application, and how to perform unit test with JUnit 5 and mocking with Mockito framework.
1. Maven
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.mkyong.spring</groupId>
<artifactId>testing-junit5-mockito</artifactId>
<version>1.0</version>
<properties>
<java.version>1.8</java.version>
<junit-jupiter.version>5.3.2</junit-jupiter.version>
<mockito.version>2.24.0</mockito.version>
</properties>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.2.RELEASE</version>
</parent>
<dependencies>
<!-- mvc -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- exclude junit 4 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
</exclusion>
</exclusions>
</dependency>
<!-- junit 5 -->
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-engine</artifactId>
<version>${junit-jupiter.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<optional>true</optional>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.22.0</version>
</plugin>
</plugins>
</build>
</project>
Display the project dependencies.
$ mvn dependency:tree
[INFO] com.mkyong.spring:testing-junit5-mockito:jar:1.0
[INFO] +- org.springframework.boot:spring-boot-starter-web:jar:2.1.2.RELEASE:compile
[INFO] | +- org.springframework.boot:spring-boot-starter:jar:2.1.2.RELEASE:compile
[INFO] | | +- org.springframework.boot:spring-boot-starter-logging:jar:2.1.2.RELEASE:compile
[INFO] | | | +- ch.qos.logback:logback-classic:jar:1.2.3:compile
[INFO] | | | | \- ch.qos.logback:logback-core:jar:1.2.3:compile
[INFO] | | | +- org.apache.logging.log4j:log4j-to-slf4j:jar:2.11.1:compile
[INFO] | | | | \- org.apache.logging.log4j:log4j-api:jar:2.11.1:compile
[INFO] | | | \- org.slf4j:jul-to-slf4j:jar:1.7.25:compile
[INFO] | | +- javax.annotation:javax.annotation-api:jar:1.3.2:compile
[INFO] | | \- org.yaml:snakeyaml:jar:1.23:runtime
[INFO] | +- org.springframework.boot:spring-boot-starter-json:jar:2.1.2.RELEASE:compile
[INFO] | | +- com.fasterxml.jackson.core:jackson-databind:jar:2.9.8:compile
[INFO] | | | +- com.fasterxml.jackson.core:jackson-annotations:jar:2.9.0:compile
[INFO] | | | \- com.fasterxml.jackson.core:jackson-core:jar:2.9.8:compile
[INFO] | | +- com.fasterxml.jackson.datatype:jackson-datatype-jdk8:jar:2.9.8:compile
[INFO] | | +- com.fasterxml.jackson.datatype:jackson-datatype-jsr310:jar:2.9.8:compile
[INFO] | | \- com.fasterxml.jackson.module:jackson-module-parameter-names:jar:2.9.8:compile
[INFO] | +- org.springframework.boot:spring-boot-starter-tomcat:jar:2.1.2.RELEASE:compile
[INFO] | | +- org.apache.tomcat.embed:tomcat-embed-core:jar:9.0.14:compile
[INFO] | | +- org.apache.tomcat.embed:tomcat-embed-el:jar:9.0.14:compile
[INFO] | | \- org.apache.tomcat.embed:tomcat-embed-websocket:jar:9.0.14:compile
[INFO] | +- org.hibernate.validator:hibernate-validator:jar:6.0.14.Final:compile
[INFO] | | +- javax.validation:validation-api:jar:2.0.1.Final:compile
[INFO] | | +- org.jboss.logging:jboss-logging:jar:3.3.2.Final:compile
[INFO] | | \- com.fasterxml:classmate:jar:1.4.0:compile
[INFO] | +- org.springframework:spring-web:jar:5.1.4.RELEASE:compile
[INFO] | | \- org.springframework:spring-beans:jar:5.1.4.RELEASE:compile
[INFO] | \- org.springframework:spring-webmvc:jar:5.1.4.RELEASE:compile
[INFO] | +- org.springframework:spring-aop:jar:5.1.4.RELEASE:compile
[INFO] | +- org.springframework:spring-context:jar:5.1.4.RELEASE:compile
[INFO] | \- org.springframework:spring-expression:jar:5.1.4.RELEASE:compile
[INFO] +- org.springframework.boot:spring-boot-starter-test:jar:2.1.2.RELEASE:test
[INFO] | +- org.springframework.boot:spring-boot-test:jar:2.1.2.RELEASE:test
[INFO] | +- org.springframework.boot:spring-boot-test-autoconfigure:jar:2.1.2.RELEASE:test
[INFO] | +- com.jayway.jsonpath:json-path:jar:2.4.0:test
[INFO] | | +- net.minidev:json-smart:jar:2.3:test
[INFO] | | | \- net.minidev:accessors-smart:jar:1.2:test
[INFO] | | | \- org.ow2.asm:asm:jar:5.0.4:test
[INFO] | | \- org.slf4j:slf4j-api:jar:1.7.25:compile
[INFO] | +- org.assertj:assertj-core:jar:3.11.1:test
[INFO] | +- org.mockito:mockito-core:jar:2.24.0:test
[INFO] | | +- net.bytebuddy:byte-buddy:jar:1.9.7:test
[INFO] | | +- net.bytebuddy:byte-buddy-agent:jar:1.9.7:test
[INFO] | | \- org.objenesis:objenesis:jar:2.6:test
[INFO] | +- org.hamcrest:hamcrest-core:jar:1.3:test
[INFO] | +- org.hamcrest:hamcrest-library:jar:1.3:test
[INFO] | +- org.skyscreamer:jsonassert:jar:1.5.0:test
[INFO] | | \- com.vaadin.external.google:android-json:jar:0.0.20131108.vaadin1:test
[INFO] | +- org.springframework:spring-core:jar:5.1.4.RELEASE:compile
[INFO] | | \- org.springframework:spring-jcl:jar:5.1.4.RELEASE:compile
[INFO] | +- org.springframework:spring-test:jar:5.1.4.RELEASE:test
[INFO] | \- org.xmlunit:xmlunit-core:jar:2.6.2:test
[INFO] | \- javax.xml.bind:jaxb-api:jar:2.3.1:test
[INFO] | \- javax.activation:javax.activation-api:jar:1.2.0:test
[INFO] +- org.junit.jupiter:junit-jupiter-engine:jar:5.3.2:test
[INFO] | +- org.apiguardian:apiguardian-api:jar:1.0.0:test
[INFO] | +- org.junit.platform:junit-platform-engine:jar:1.3.2:test
[INFO] | | +- org.junit.platform:junit-platform-commons:jar:1.3.2:test
[INFO] | | \- org.opentest4j:opentest4j:jar:1.1.1:test
[INFO] | \- org.junit.jupiter:junit-jupiter-api:jar:5.3.2:test
[INFO] \- org.springframework.boot:spring-boot-devtools:jar:2.1.2.RELEASE:compile (optional)
[INFO] +- org.springframework.boot:spring-boot:jar:2.1.2.RELEASE:compile
[INFO] \- org.springframework.boot:spring-boot-autoconfigure:jar:2.1.2.RELEASE:compile
2. Test Spring Boot + JUnit 5 + Mockito.
2.1 Test the following Spring components.
HelloServiceImpl.java
package com.mkyong.core.services;
import com.mkyong.core.repository.HelloRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
public class HelloServiceImpl implements HelloService {
@Autowired
HelloRepository helloRepository;
@Override
public String get() {
return helloRepository.get();
}
}
HelloRepositoryImpl.java
package com.mkyong.core.repository;
import org.springframework.stereotype.Repository;
@Repository
public class HelloRepositoryImpl implements HelloRepository {
@Override
public String get() {
return "Hello JUnit 5";
}
}
2.2 JUnit 5
HelloServiceTest.java
package com.mkyong.core.services;
import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import static org.junit.jupiter.api.Assertions.assertEquals;
@SpringBootTest
public class HelloServiceTest {
@Autowired
HelloService helloService;
@DisplayName("Test Spring @Autowired Integration")
@Test
void testGet() {
assertEquals("Hello JUnit 5", helloService.get());
}
}
2.3 Mockito.
HelloServiceMockTest.java
package com.mkyong.core.services;
import com.mkyong.core.repository.HelloRepository;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Test;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.springframework.boot.test.context.SpringBootTest;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.mockito.Mockito.when;
@SpringBootTest
public class HelloServiceMockTest {
@Mock
private HelloRepository helloRepository;
@InjectMocks // auto inject helloRepository
private HelloService helloService = new HelloServiceImpl();
@BeforeEach
void setMockOutput() {
when(helloRepository.get()).thenReturn("Hello Mockito From Repository");
}
@DisplayName("Test Mock helloService + helloRepository")
@Test
void testGet() {
assertEquals("Hello Mockito From Repository", helloService.get());
}
}
3. Test Spring MVC Controller.
3.1 MVC controller.
MainController.java
package com.mkyong.core.controller;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ResponseBody;
@Controller
public class MainController {
@ResponseBody
@GetMapping("/")
public String hello() {
return "Hello Controller";
}
}
3.2 JUnit 5 and MVC test.
MainControllerTest.java
package com.mkyong.core.controller;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.boot.test.context.SpringBootTest.WebEnvironment;
import org.springframework.boot.test.web.client.TestRestTemplate;
import org.springframework.boot.web.server.LocalServerPort;
import org.springframework.http.ResponseEntity;
import java.net.URL;
import static org.junit.jupiter.api.Assertions.assertEquals;
@SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
public class MainControllerTest {
// bind the above RANDOM_PORT
@LocalServerPort
private int port;
@Autowired
private TestRestTemplate restTemplate;
@Test
public void getHello() throws Exception {
ResponseEntity<String> response = restTemplate.getForEntity(
new URL("http://localhost:" + port + "/").toString(), String.class);
assertEquals("Hello Controller", response.getBody());
}
}
Done.
I don’t get it why are you using @SpringBootTest everywhere.
This is a bad example and other can copy and implement.
There are alternatives @SpringBootTest because this annotations fires up the entire sprint context.
helloService = new HelloServiceImpl(); – this is not very good honestly. The better Spring way is to use @Autowired, right?
We need to inject the repository mock object via
@InjectMocks
Maybe I’m not rigth… But when I use @InjectMocks Using the implementation of our service works too.
@InjectMocks
private HelloServiceImpl service;
It works as @Autowired.
Anyway. Thanks mkyong, as always… Your posts are helpful.
Hi, Thanks Kyong, I had to add spring.main.allow-bean-definition-overriding: true in the applicaiton.yaml file to get rid of BeanOverridingException. I don’t see that in your Git repo. How were you able to run without this property. Thanks
i see that there is a property “mockito.version” in pom file. but where is it used?
how mockito dependency is declared?
ok i saw the dependency tree. its coming from spring-boot-starter-test
Thank you for great article. btw, you misspelled from “Hello Mockito From Responsitory”. (*Repository mean)
Thanks, article is updated.
thank you so much
Your posts have helped me more than any other personal site.
How do you test a suite of tests with this library? including tests in multiple test classes and tests in multiple packages.
In real scenario, I have @Autowired say OtherService otherService; inside HelloServiceImpl.
Then the Autowired otherServie will be null inside HelloServiceImpl . How can we handle that ?
Thank you.
If you like me, your BaseClass extends AbstractTransactionalJUnit4SpringContextTests
The @MockBean will always be null.
You can find solution here 🙂
https://github.com/spring-projects/spring-boot/issues/9609
Not working. TestRestTemplate object returns null.
Hi,
I am getting
java.lang.NoClassDefFoundError: org/junit/platform/commons/PreconditionViolationException
at org.eclipse.jdt.internal.junit5.runner.JUnit5TestLoader.createUnfilteredTest(JUnit5TestLoader.java:75)
at org.eclipse.jdt.internal.junit5.runner.JUnit5TestLoader.createTest(JUnit5TestLoader.java:66)
at org.eclipse.jdt.internal.junit5.runner.JUnit5TestLoader.loadTests(JUnit5TestLoader.java:53)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:525)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:763)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:463)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:209)
After removing m2 and re-starting eclipse it worked.
Does this create Mockito tests using Junit 5 as the base, or is this only showing how to use Mockito which is based on Junit4?
Yes, JUnit 5