Spring MVC Concepts

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Internal

To Process

TO PROCESS:

Controller

A controller is a class that handles requests and responds with information of some sort. In case of a browser-facing application, a controller responds by optionally populating model data and passing the request to a view that produces HTML to be returned to the browser. The view is indicated by its logical name, which is returned by the method.

@Controller @GetMapping

@Controller
public class HomeController {

    @GetMapping("/")
    public String home() {

        // returns the view name
        return "home";
    }
}

View

The view is instantiated dynamically, and its implementation depends on the template engine that is available in the classpath. The template name is derived from the logical name by prefixing it with /templates and postfixing it with .html. Simply placing a <logical-view-name>.html under src/resources/templates makes the template-based view available.

View Logical Name

Project Directory Layout

src/main/resource/static
src/main/resource/static/images
src/main/resource/templates

Testing MVC Applications

import org.springframework.test.web.servlet.MockMvc;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.view;
import static org.hamcrest.Matchers.containsString;

@RunWith(SpringRunner.class)
@WebMvcTest(HomeController.class)
public class HomeControllerTest {

    @Autowired
    private MockMvc mockMvc;

    @Test
    public void testHomePage() throws Exception {

        mockMvc.perform(get("/")).
                andExpect(status().isOk()).
                andExpect(view().name("home")).
                andExpect(content().string(containsString("Welcome to ...")));
    }
}

@WebMvcTest

MockMvc

REST Clients

RestTemplate

TO PROCESS: https://docs.spring.io/spring/docs/current/spring-framework-reference/web.html#webmvc-resttemplate

POSTing Resource. Data

This overloaded version allows you to receive the newly created resource as a domain model object:

RestTemplate restTemplate = new RestTemplate();

MyResource model = new MyResource(...);

MyResource created = restTemplate.postForObject("http://localhost:8080/myresource", model, MyResource.class);