DATAREST-880 - Prevent nested-entity-as-resource handling for unwrapped properties.

We now exclude properties that are marked as to be unwrapped from getting the nested-entity-as-resource behavour applied as it doesn't make any sense.

spring-data-rest-tests/spring-data-rest-tests-jpa/src/main/java/org/springframework/data/rest/webmvc/jpa/CreditCard.java

@@ -15,14 +15,34 @@
  */
 package org.springframework.data.rest.webmvc.jpa;
 
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.RequiredArgsConstructor;
+
+import javax.persistence.Embeddable;
 import javax.persistence.Entity;
 import javax.persistence.Id;
 
+import com.fasterxml.jackson.annotation.JsonUnwrapped;
+
 /**
  * @author Oliver Gierke
  */
 @Entity
+@Getter
+@NoArgsConstructor(force = true)
+@RequiredArgsConstructor
 public class CreditCard {
 
 	@Id Long id;
+	final @JsonUnwrapped CCN ccn;
+
+	@Embeddable
+	@Getter
+	@NoArgsConstructor(force = true)
+	@AllArgsConstructor
+	public static class CCN {
+		String ccn;
+	}
 }

spring-data-rest-tests/spring-data-rest-tests-jpa/src/test/java/org/springframework/data/rest/webmvc/json/PersistentEntitySerializationTests.java

@@ -36,6 +36,7 @@ import org.springframework.data.projection.ProjectionFactory;
 import org.springframework.data.projection.SpelAwareProxyProjectionFactory;
 import org.springframework.data.repository.support.Repositories;
 import org.springframework.data.rest.webmvc.PersistentEntityResource;
+import org.springframework.data.rest.webmvc.jpa.CreditCard;
 import org.springframework.data.rest.webmvc.jpa.JpaRepositoryConfig;
 import org.springframework.data.rest.webmvc.jpa.LineItem;
 import org.springframework.data.rest.webmvc.jpa.Order;
@@ -289,4 +290,15 @@ public class PersistentEntitySerializationTests {
 
 		assertThat(JsonPath.read(result, "$._links.self"), is(notNullValue()));
 	}
+
+	/**
+	 * @see DATAREST-880
+	 */
+	@Test
+	public void unwrapsNestedTypeCorrectly() throws Exception {
+
+		CreditCard creditCard = new CreditCard(new CreditCard.CCN("1234123412341234"));
+
+		assertThat(JsonPath.read(mapper.writeValueAsString(creditCard), "$.ccn"), is("1234123412341234"));
+	}
 }

spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/json/PersistentEntityJackson2Module.java

@@ -273,7 +273,7 @@ public class PersistentEntityJackson2Module extends SimpleModule {
 					continue;
 				}
 
-				if (persistentProperty.isEntity()) {
+				if (persistentProperty.isEntity() && !writer.isUnwrapping()) {
 
 					LOG.debug("Assigning nested entity serializer for {}.", persistentProperty);