From 893f2c8c41d0c06a70d6562e3fb9f83c9c1ab914 Mon Sep 17 00:00:00 2001
From: Greg Turnquist <gturnquist@gopivotal.com>
Date: Fri, 18 Jul 2014 14:12:26 -0500
Subject: [PATCH] @Entity with @Embedded List<T> causes it to not render
 propertly

This test case exposes a glitch in Spring Data REST, probably because it confused when handling more than one item when rendering a link.

In the test case, change LineItem inside Order to List<LineItem> to simulate multiple entries, and the the line items themselves won't render
the target property, probably because the target property needs to move from top level _links to an embedded link for each line Item
---
 .../rest/webmvc/jpa/DataRest262Tests.java     | 53 +++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/webmvc/jpa/DataRest262Tests.java b/spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/webmvc/jpa/DataRest262Tests.java
index cd3a887bc..5c0f13f73 100644
--- a/spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/webmvc/jpa/DataRest262Tests.java
+++ b/spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/webmvc/jpa/DataRest262Tests.java
@@ -24,8 +24,11 @@ import javax.persistence.Entity;
 import javax.persistence.GeneratedValue;
 import javax.persistence.Id;
 import javax.persistence.ManyToOne;
+import javax.persistence.OneToOne;
 import javax.validation.constraints.NotNull;
 
+import java.io.IOException;
+
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -117,11 +120,39 @@ public class DataRest262Tests {
 
 		String result = mapper.writeValueAsString(resource);
 
+		System.out.println(result);
+
 		assertThat(JsonPath.read(result, "$_links.self"), is(notNullValue()));
 		assertThat(JsonPath.read(result, "$_links.airport"), is(notNullValue()));
 		assertThat(JsonPath.read(result, "$_links.originOrDestinationAirport"), is(notNullValue()));
 	}
 
+	@Test
+	public void serializeCircularReference() throws IOException, InterruptedException {
+
+		Order order = new Order();
+		order.name = "Shopping basket #1";
+		order.id = 1L;
+		//relatedOrder.lineItems = new ArrayList<LineItem>();
+
+		LineItem lineItem = new LineItem();
+		lineItem.description = "iPhone case";
+		lineItem.target = order;
+
+		//relatedOrder.lineItems.add(lineItem);
+		order.lineItem = lineItem;
+
+		JpaPersistentEntity<?> persistentEntity = mappingContext.getPersistentEntity(Order.class);
+
+		Resource<Object> resource = PersistentEntityResource.build(order, persistentEntity).//
+				withLink(new Link("/api/relatedOrder/" + order.id)).//
+				build();
+
+		String result = mapper.writeValueAsString(resource);
+
+		System.out.println(result);
+	}
+
 	public interface AircraftMovementRepository extends CrudRepository<AircraftMovement, Long> {
 
 	}
@@ -130,6 +161,10 @@ public class DataRest262Tests {
 
 	}
 
+	public interface OrderRepository extends CrudRepository<Order, Long> {
+
+	}
+
 	@Entity(name = "aircraftmovement")
 	public static class AircraftMovement {
 
@@ -140,11 +175,29 @@ public class DataRest262Tests {
 
 	@Embeddable
 	public static class FlightPart {
+
 		@ManyToOne Airport airport;
 	}
 
 	@Entity(name = "airport")
 	public static class Airport {
+
 		@Id @GeneratedValue Long id;
 	}
+
+	@Entity(name = "system")
+	public static class Order {
+
+		@Id @GeneratedValue Long id;
+		String name;
+		// Change lineItem to List<LineItem>, and the whole field gets dropped
+		@Embedded LineItem lineItem;
+	}
+
+	@Embeddable
+	public static class LineItem {
+
+		@OneToOne Order target;
+		String description;
+	}
 }