Test Spring Mvc controller and inject static class - spring-mvc

Question

The following code is the standard method to write a JUnit test for a Mvc controller.
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes = ApplicationTestCassandra.class)
#WebAppConfiguration
public class TestControllerTests {
#Autowired
private WebApplicationContext webApplicationContext;
private MockMvc mockMvc;
#Before
public void setup() throws Exception {
this.mockMvc = webAppContextSetup(webApplicationContext).build();
}
#Test
public void testupTimeStart() throws Exception {
this.mockMvc.perform(get("/uptime"))
.andExpect(status().isOk());
}
}
This works fine, but I would like to replace an autowired class with a special class for testing. The class CassandraSimpleConnection is injected via #Autowired in my controller.
I have tried several approaches, but no luck.
The following code fails because of an Mvc 404 error, because I guess my application with the REST interface is not running at all.
#RunWith(SpringJUnit4ClassRunner.class)
//ApplicationTestCassandra is SpringBoot application startpoint class with #SpringBootApplication annotation
//#ContextConfiguration(classes = ApplicationTestCassandra.class, loader = AnnotationConfigContextLoader.class)
#ContextConfiguration(loader = AnnotationConfigWebContextLoader.class)//, classes = {ApplicationTestCassandra.class})
#WebAppConfiguration
public class TestControllerTests {
#Service
#EnableWebMvc
#ComponentScan(basePackages={"blabla.functionalTests"})
static class CassandraSimpleConnection {
public Metadata testConnection(TestConfiguration configuration) {
Metadata metadata = null;
// return metadata;
throw new RuntimeException("Could not connect to any server");
}
}
If I use
#ContextConfiguration(loader = AnnotationConfigWebContextLoader.class, classes = {ApplicationTestCassandra.class})
CassandraSimpleConnection is not replaced with my static class.
Could somebody help me please? The documentation about the annotations is quite confusing.

Answer 1

Read the comments and here is the solution:
#RunWith(SpringRunner.class)
#SpringBootTest(classes = { MyApplication.class })
public class MyTests {
#MockBean
private MyBeanClass myTestBean;
#Before
public void setup() {
...
when(myTestBean.doSomething()).thenReturn(someResult);
}
#Test
public void test() {
// MyBeanClass bean is replaced with myTestBean in the ApplicationContext here
}
}