GH-2529 - More stable entity detection with dynamic labels.

Closes #2529

Author: meistermeier

src/main/java/org/springframework/data/neo4j/core/mapping/NodeDescriptionStore.java

@@ -24,6 +24,7 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.function.BiFunction;
+import java.util.function.Function;
 
 import org.springframework.data.mapping.context.AbstractMappingContext;
 import org.springframework.lang.Nullable;
@@ -122,10 +123,10 @@ private NodeDescriptionAndLabels computeConcreteNodeDescription(NodeDescription<
 			List<String> mostMatchingStaticLabels = null;
 
 			// Remove is faster than "stream, filter, count".
-			BiFunction<NodeDescription<?>, List<String>,  Integer> unmatchedLabelsCount =
-					(nodeDescription, staticLabels) -> {
-						Set<String> staticLabelsClone = new HashSet<>(staticLabels);
-						labels.forEach(staticLabelsClone::remove);
+			Function<NodeDescription<?>, Integer> unmatchedLabelsCount =
+					(nodeDescription) -> {
+						Set<String> staticLabelsClone = new HashSet<>(labels);
+						nodeDescription.getStaticLabels().forEach(staticLabelsClone::remove);
 						return staticLabelsClone.size();
 					};
 
@@ -138,14 +139,16 @@ private NodeDescriptionAndLabels computeConcreteNodeDescription(NodeDescription<
 					return new NodeDescriptionAndLabels(nd, surplusLabels);
 				}
 
-				unmatchedLabelsCache.put(nd, unmatchedLabelsCount.apply(nd, staticLabels));
+				unmatchedLabelsCache.put(nd, unmatchedLabelsCount.apply(nd));
 				if (mostMatchingNodeDescription == null) {
 					mostMatchingNodeDescription = nd;
 					mostMatchingStaticLabels = staticLabels;
 					continue;
 				}
 
-				if (unmatchedLabelsCache.get(nd) < unmatchedLabelsCache.get(mostMatchingNodeDescription)) {
+				Integer newUnmatchedLabelCount = unmatchedLabelsCache.get(nd);
+				Integer existingUnmatchedLabelCount = unmatchedLabelsCache.get(mostMatchingNodeDescription);
+				if (newUnmatchedLabelCount < existingUnmatchedLabelCount) {
 					mostMatchingNodeDescription = nd;
 				}
 			}

src/test/java/org/springframework/data/neo4j/integration/imperative/DynamicLabelsIT.java

@@ -41,6 +41,8 @@
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.data.neo4j.repository.Neo4jRepository;
+import org.springframework.data.neo4j.repository.config.EnableNeo4jRepositories;
 import org.springframework.data.neo4j.test.Neo4jImperativeTestConfiguration;
 import org.springframework.data.neo4j.config.Neo4jEntityScanner;
 import org.springframework.data.neo4j.core.DatabaseSelectionProvider;
@@ -434,6 +436,34 @@ void shouldReadDynamicLabelsInInheritance(@Autowired Neo4jTemplate template) {
 		}
 	}
 
+	@Nested
+	class ClassesWithInheritanceAndDynamicLabels extends SpringTestBase {
+
+		@Override
+		Long createTestEntity(Transaction t) {
+			return null;
+		}
+
+		@Test
+		void instantiateConcreteEntityType(@Autowired AbstractBaseEntityWithDynamicLabelsRepository repository) {
+			EntitiesWithDynamicLabels.EntityWithMultilevelInheritanceAndDynamicLabels entity =
+					new EntitiesWithDynamicLabels.EntityWithMultilevelInheritanceAndDynamicLabels();
+			entity.labels = Collections.singleton("AdditionalLabel");
+			entity.name = "Name";
+			entity.id = "ID1";
+
+			repository.save(entity);
+
+			EntitiesWithDynamicLabels.EntityWithMultilevelInheritanceAndDynamicLabels loadedEntity =
+					(EntitiesWithDynamicLabels.EntityWithMultilevelInheritanceAndDynamicLabels) repository.findById("ID1").get();
+
+			assertThat(loadedEntity.labels).contains("AdditionalLabel");
+		}
+
+	}
+
+	interface AbstractBaseEntityWithDynamicLabelsRepository extends Neo4jRepository<EntitiesWithDynamicLabels.AbstractBaseEntityWithDynamicLabels, String> {}
+
 	@ExtendWith(SpringExtension.class)
 	@ContextConfiguration(classes = SpringTestBase.Config.class)
 	@DirtiesContext
@@ -486,6 +516,7 @@ protected final List<String> getLabels(Condition idCondition, Object id) {
 
 		@Configuration
 		@EnableTransactionManagement
+		@EnableNeo4jRepositories(considerNestedRepositories = true)
 		static class Config extends Neo4jImperativeTestConfiguration {
 
 			@Bean

src/test/java/org/springframework/data/neo4j/integration/shared/common/EntitiesWithDynamicLabels.java

@@ -178,5 +178,37 @@ public static class EntityWithCustomIdAndDynamicLabels {
 		@DynamicLabels public Set<String> myLabels;
 	}
 
+	/**
+	 * Base entity for the multi-level abstraction
+	 */
+	@Node
+	public static abstract class BaseEntityWithoutDynamicLabels {
+		@Id public String id;
+	}
+
+	/**
+	 * adds the labels
+	 */
+	@Node
+	public static abstract class AbstractBaseEntityWithDynamicLabels extends BaseEntityWithoutDynamicLabels {
+		@DynamicLabels public Set<String> labels;
+	}
+
+	/**
+	 * This might be the wrong most concrete class to be found
+	 */
+	@Node
+	public static abstract class AbstractEntityWithDynamicLabels extends AbstractBaseEntityWithDynamicLabels {
+
+	}
+
+	/**
+	 * ...but this is the right one
+	 */
+	@Node
+	public static class EntityWithMultilevelInheritanceAndDynamicLabels extends AbstractEntityWithDynamicLabels {
+		public String name;
+	}
+
 	private EntitiesWithDynamicLabels() {}
 }