#1515 - Fix key rendering of embedded resources.

We now also eagerly map the keys for the _embedded map in a HAL response to Strings to make sure they work properly when sorting of map keys is activated for the Jackson ObjectMapper.

src/main/java/org/springframework/hateoas/mediatype/hal/Jackson2HalModule.java

@@ -21,6 +21,7 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.function.Function;
@@ -333,7 +334,11 @@ public class Jackson2HalModule extends SimpleModule {
 				}
 			}
 
-			provider.findValueSerializer(Map.class, property).serialize(embeddeds, jgen, provider);
+			Map<String, Object> map = new LinkedHashMap<>(embeddeds.size());
+			embeddeds.forEach((key, it) -> map.put(key.value(), it));
+
+			provider.findValueSerializer(Map.class, property) //
+					.serialize(map, jgen, provider);
 		}
 
 		/*

src/test/java/org/springframework/hateoas/mediatype/hal/Jackson2HalIntegrationTest.java

@@ -644,6 +644,15 @@ class Jackson2HalIntegrationTest {
 				.writeValueAsString(new RepresentationModel<>().add(Link.of("/href")));
 	}
 
+	@Test // #1515
+	void rendersEmbeddedKeysWhenMapEntrySortingIsEnabled() throws Exception {
+
+		List<SimplePojo> embbededs = Arrays.asList(new SimplePojo(), new SimpleAnnotatedPojo());
+
+		mapper.enable(SerializationFeature.ORDER_MAP_ENTRIES_BY_KEYS)
+				.writeValueAsString(CollectionModel.of(embbededs));
+	}
+
 	@Test // #1516
 	void considersNamingBase() throws Exception {