Testing Web Endpoints in Isolation Using MockMvc

@RestController
@RequestMapping("/api/hello")
public class HelloController {
    @GetMapping
    public String sayHello() {
        return "Hello Spring!";
    }
}
 
@WebMvcTest(HelloController.class)
public class HelloControllerTest {
 
    @Autowired
    private MockMvc mockMvc;
 
    @Test
    public void testSayHelloEndpoint() throws Exception {
        mockMvc.perform(MockMvcRequestBuilders.get("/api/hello"))
               .andExpect(MockMvcResultMatchers.status().isOk())
               .andExpect(MockMvcResultMatchers.content().string("Hello Spring!"));
    }
}