Null Pointer when using #SpringBootTest - spring-boot

Question

I am using spring boot 1.4,
when using the #SpringBootTest annotation for integration test, it gives a null pointer.
#RunWith(SpringRunner.class);
#SpringBootTest
public class MyControllerTest {
#Test
public void mytest {
when().
get("/hello").
then().
body("hello");
}
}
and for main class:
#SpringApplication
#EnableCaching
#EnableAsync
public class HelloApp extends AsyncConfigureSupport {
public static void main(String[] args) {
SpringApplication.run(HelloApp.class, args);
}
#Override
public Executor getAsyncExecutor() {
...
}
}
Then in my controller:
#RestController
public class HelloController {
#Autowired
private HelloService helloService;
#RequestMapping("/hello");
public String hello() {
return helloService.sayHello();
}
}
HelloService
#Service
public class HelloService {
public String sayHello() {
return "hello";
}
}
But it ways says NullPointException when for helloService when processing request.
What am I missing?

Answer 1

You need to mock HelloService in your test class as your controller is calling a service .Here in your case Your Test class is not aware that there is any service available or not

Answer 2

The following example test class might help you. In this guide from spring an example is shown how to integration test a rest controller in a spring fashion way.
#RunWith(SpringRunner.class)
#SpringBootTest
#WebAppConfiguration
public class HelloControllerTest {
private MockMvc mockMvc;
#Autowired
private WebApplicationContext webApplicationContext;
#Before
public void setUp() {
this.mockMvc = MockMvcBuilders.webAppContextSetup(webApplicationContext).build();
}
#Test
public void hello() throws Exception {
mockMvc.perform(get("/hello")).andExpect(content().string("hello"));
}
}