How to mock a spring bean?

Question

I'm trying to mock an class that uses JAXRS and this class are a spring component.

@Component
public class PostmanClient {

  private WebTarget target;

  public PostmanClient() {
    Client client = ClientBuilder.newClient();
    target = client.target(...);
  }

  public String send(String xml) {
    Builder requestBuilder = target.request(MediaType.APPLICATION_XML_TYPE);
    Response response = requestBuilder.post(Entity.entity(xml, MediaType.APPLICATION_XML_TYPE));
    return response.readEntity(String.class);
  }
}

This is my test method:

@Test
public void processPendingRegistersWithAutomaticSyncJob() throws Exception {
  PostmanClient postmanClient = mock(PostmanClient.class);
  String response = "OK";
  whenNew(PostmanClient.class).withNoArguments().thenReturn(postmanClient);
  when(postmanClient.send("blablabla")).thenReturn(response);

  loadApplicationContext(); // applicationContext = new ClassPathXmlApplicationContext("/test-context.xml");
}

When i debug the postmanClient instance, its a instance created by Spring and not a mock. How can i avoid this behavior and get a mock instance ?

It's generally a bad idea to mix mocking into an integration test. Either don't load beans via Spring with `loadApplicationContext`, or use a different profile to load a manually stubbed PostmanClient for your tests. — Thorn G, Jun 26 '14 at 21:14
Yes, but i don't want create a restful server to respond the postmanClient. The other way is to use a framework that mock restful services like restito or mock-server. — Sandro Simas, Jun 27 '14 at 02:33
http://stackoverflow.com/questions/10906945/mockito-junit-and-spring/10924843#10924843 This question should give you some idea on how to do it. Though I am not recommend doing so, especially for unit testing — Adrian Shum, Jun 27 '14 at 07:58

score 0 · Answer 1 · answered Jun 26 '14 at 21:57

0

If you are using PowerMock with Spring, you should consider following tips:
1. Use @RunWith(SpringJunit4Runner.class)
2. Use @ContextConfiguration("/test-context.xml") // load spring context before test
3. Use @PrepareForTest(....class) // to mock static method
4. Use PowerMockRule
5. The simplest way to mock a spring bean is to use springockito

Back To You Question:
If I don't understand you wrong, you have PostmanClient defined in spring context, which means, you only need use springockito to achieve your goal, just follow the tutorial on springockito page.

answered Jun 26 '14 at 21:57

Jaiwo99

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I don't want to use SpringJunit4Runner because i need to load datasets on database with DBUnit before spring context load. I try to use spring-test-dbunit but the framework listener always execute after spring context listener. Because of this i choose to load dataset and create the application context programmatically. Doing this way i need to create the mocks before all mentioned above. – Sandro Simas Jun 27 '14 at 02:31
@SandroSimas, you may use jUnit Spring Rule. Like in my example. https://github.com/thekingnothing/mockito-junit-spring-rules But I doubt that you need mock object in integration tests. – Artur Zagretdinov Mar 01 '16 at 09:37

score 0 · Answer 2 · answered Jun 27 '14 at 04:23

You can use BDD framework Spock to write UT for your Spring Framework. With Spock Spring extension (Maven: groupId:org.spockframework, artifactId:spock-spring), you can load Spring context in your unit test.

@WebAppConfiguration
@ContextConfiguration(classes = Application.class)
class MyServiceSpec extends Specification {
    @Autowired
    UserRepository userRepository
}

If you have some beans you want to mock them instead of loading from Spring context, you can add following annotation on the bean you want to mock.

@ReplaceWithMock

This article has the detailed intro about how to write UT for your Spring app with Spock.

score 0 · Answer 3 · answered Jun 27 '14 at 07:49

0

Im not sure what is wrong with your implementation. Maybe PostmanClient should be an interface instead of class?

However I've implemented a similar unit test in my practice/test project. Maybe it will help:

https://github.com/oipat/poht/blob/683b401145d4a4c2bace49f356a5aa401fe81eb1/backend/src/test/java/org/tapiok/blogi/service/impl/PostServiceImplTest.java

answered Jun 27 '14 at 07:49

user2170710

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But you are not using Spring – Sandro Simas Jun 27 '14 at 13:55

score 0 · Answer 4 · answered Sep 06 '15 at 13:09

Register your mock with Spring-ReInject before the application context starts in your test's constructor. The original bean will be replaced with a mock, and the mock will be used by Spring everywhere, including injected fields. The original bean will be never created.

score 0 · Answer 5 · answered Feb 29 '16 at 20:13

0

There is an option to fake Spring bean with just plain Spring features. You need to use @Primary, @Profile and @ActiveProfiles annotations for it.

I wrote a blog post on the topic.

answered Feb 29 '16 at 20:13

luboskrnac

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score 0 · Answer 6 · answered Feb 29 '16 at 20:36

I've created the example to answer another question, but also cover your case. Simple replace MockitoJUnitRunner via SpringJUnit4ClassRunner.

In nutshell, I create Java Spring Configuration which includes only classes which should be tested/mocked and returns mocked object instead really object, and then give Spring does it work. Very simple and flexible solution.

It also works fine with MvcMock

score 0 · Answer 7 · answered Jan 14 '17 at 11:18

0

As of Spring Boot 1.4.x you can use new annotation called @MockBean.

answered Jan 14 '17 at 11:18

luboskrnac

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How to mock a spring bean?

7 Answers7