DATAREST-661 - Fixed non-existant resource detection for PATCH requests.

PATCH requests to non existing resource now correctly return 404 Not Found as PersistentEntityResourceHandlerMethodArgumentResolver.read(…) now correctly throws the ResourceNotFoundException.

spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/config/PersistentEntityResourceHandlerMethodArgumentResolver.java

@@ -155,7 +155,7 @@ public class PersistentEntityResourceHandlerMethodArgumentResolver implements Ha
 		if (request.isPatchRequest() && converter instanceof MappingJackson2HttpMessageConverter) {
 
 			if (objectToUpdate == null) {
-				new ResourceNotFoundException();
+				throw new ResourceNotFoundException();
 			}
 
 			ObjectMapper mapper = ((MappingJackson2HttpMessageConverter) converter).getObjectMapper();

spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/webmvc/CommonWebTests.java

@@ -24,6 +24,7 @@ import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.
 
 import net.minidev.json.JSONArray;
 
+import java.net.URI;
 import java.util.List;
 import java.util.Map;
 
@@ -31,6 +32,7 @@ import org.junit.Test;
 import org.springframework.hateoas.Link;
 import org.springframework.hateoas.Links;
 import org.springframework.hateoas.MediaTypes;
+import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
 import org.springframework.mock.web.MockHttpServletResponse;
 import org.springframework.test.web.servlet.ResultActions;
@@ -242,4 +244,27 @@ public abstract class CommonWebTests extends AbstractWebIntegrationTests {
 			assertThat(links.hasLink("profile"), is(true));
 		}
 	}
+
+	/**
+	 * @see DATAREST-661
+	 */
+	@Test
+	public void patchToNonExistingResourceReturnsNotFound() throws Exception {
+
+		String rel = expectedRootLinkRels().iterator().next();
+		String uri = client.discoverUnique(rel).expand().getHref().concat("/");
+		String id = "4711";
+		Integer status = null;
+
+		do {
+
+			// Try to find non existing resource
+			uri = uri.concat(id);
+			status = mvc.perform(get(URI.create(uri))).andReturn().getResponse().getStatus();
+
+		} while (status != HttpStatus.NOT_FOUND.value());
+
+		// PATCH to non-existing resource
+		mvc.perform(patch(URI.create(uri))).andExpect(status().isNotFound());
+	}
 }