Custom Media Types for REST (#918)

* Custom Media Types for REST

* add test, add DTO, remove example of API versioning to make example simpler

* client accept only that custom-media type

* remove not needed new_line

* leave custom media type on class level

spring-rest/src/test/java/org/baeldung/web/controller/mediatypes/CustomMediaTypeControllerTest.java

@@ -0,0 +1,41 @@
+package org.baeldung.web.controller.mediatypes;
+
+import org.baeldung.config.WebConfig;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.web.WebAppConfiguration;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+import org.springframework.web.context.WebApplicationContext;
+
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(classes = WebConfig.class)
+@WebAppConfiguration
+public class CustomMediaTypeControllerTest {
+
+    private MockMvc mockMvc;
+
+    @Autowired
+    private WebApplicationContext webApplicationContext;
+
+    @Before
+    public void setUp() {
+        mockMvc = MockMvcBuilders.webAppContextSetup(webApplicationContext).build();
+    }
+
+    @Test
+    public void shouldSendRequestForItem() throws Exception {
+        mockMvc.perform(get("/public/api/endpoint")
+                .contentType("application/vnd.baeldung.api.v1+json")
+                .accept("application/vnd.baeldung.api.v1+json"))
+                .andExpect(status().isOk());
+    }
+}