DATAMONGO-1827 - Polishing.

Use diamond syntax in imperative and reactive Template API implementations. Rename ReactiveMongoTemplate.toDbObject to toDocument. Move Terminating interfaces in ExecutableUpdateOperation and ExecutableRemoveOperation to the top-most position to align with other fluent interface declarations and to improve discoverability of terminating operations.

Convert ReactiveMongoTemplateTests assertions to AssertJ.

Original Pull Request: #569

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/ExecutableRemoveOperation.java

@@ -53,26 +53,6 @@ public interface ExecutableRemoveOperation {
 	 */
 	<T> ExecutableRemove<T> remove(Class<T> domainType);
 
-	/**
-	 * Collection override (optional).
-	 *
-	 * @param <T>
-	 * @author Christoph Strobl
-	 * @since 2.0
-	 */
-	interface RemoveWithCollection<T> extends RemoveWithQuery<T> {
-
-		/**
-		 * Explicitly set the name of the collection to perform the query on. <br />
-		 * Skip this step to use the default collection derived from the domain type.
-		 *
-		 * @param collection must not be {@literal null} nor {@literal empty}.
-		 * @return new instance of {@link RemoveWithCollection}.
-		 * @throws IllegalArgumentException if collection is {@literal null}.
-		 */
-		RemoveWithQuery<T> inCollection(String collection);
-	}
-
 	/**
 	 * @author Christoph Strobl
 	 * @since 2.0
@@ -104,6 +84,27 @@ public interface ExecutableRemoveOperation {
 		List<T> findAndRemove();
 	}
 
+	/**
+	 * Collection override (optional).
+	 *
+	 * @param <T>
+	 * @author Christoph Strobl
+	 * @since 2.0
+	 */
+	interface RemoveWithCollection<T> extends RemoveWithQuery<T> {
+
+		/**
+		 * Explicitly set the name of the collection to perform the query on. <br />
+		 * Skip this step to use the default collection derived from the domain type.
+		 *
+		 * @param collection must not be {@literal null} nor {@literal empty}.
+		 * @return new instance of {@link RemoveWithCollection}.
+		 * @throws IllegalArgumentException if collection is {@literal null}.
+		 */
+		RemoveWithQuery<T> inCollection(String collection);
+	}
+
+
 	/**
 	 * @author Christoph Strobl
 	 * @since 2.0

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/ExecutableUpdateOperation.java

@@ -57,6 +57,82 @@ public interface ExecutableUpdateOperation {
 	 */
 	<T> ExecutableUpdate<T> update(Class<T> domainType);
 
+	/**
+	 * Trigger findAndModify execution by calling one of the terminating methods.
+	 */
+	interface TerminatingFindAndModify<T> {
+
+		/**
+		 * Find, modify and return the first matching document.
+		 *
+		 * @return {@link Optional#empty()} if nothing found.
+		 */
+		default Optional<T> findAndModify() {
+			return Optional.ofNullable(findAndModifyValue());
+		}
+
+		/**
+		 * Find, modify and return the first matching document.
+		 *
+		 * @return {@literal null} if nothing found.
+		 */
+		@Nullable
+		T findAndModifyValue();
+	}
+
+	/**
+	 * Trigger findAndReplace execution by calling one of the terminating methods.
+	 */
+	interface TerminatingFindAndReplace<T> {
+
+		/**
+		 * Find, replace and return the first matching document.
+		 *
+		 * @return {@link Optional#empty()} if nothing found.
+		 */
+		default Optional<T> findAndReplace() {
+			return Optional.ofNullable(findAndReplaceValue());
+		}
+
+		/**
+		 * Find, replace and return the first matching document.
+		 *
+		 * @return {@literal null} if nothing found.
+		 */
+		@Nullable
+		T findAndReplaceValue();
+	}
+
+	/**
+	 * Trigger update execution by calling one of the terminating methods.
+	 *
+	 * @author Christoph Strobl
+	 * @since 2.0
+	 */
+	interface TerminatingUpdate<T> extends TerminatingFindAndModify<T>, FindAndModifyWithOptions<T> {
+
+		/**
+		 * Update all matching documents in the collection.
+		 *
+		 * @return never {@literal null}.
+		 */
+		UpdateResult all();
+
+		/**
+		 * Update the first document in the collection.
+		 *
+		 * @return never {@literal null}.
+		 */
+		UpdateResult first();
+
+		/**
+		 * Creates a new document if no documents match the filter query or updates the matching ones.
+		 *
+		 * @return never {@literal null}.
+		 */
+		UpdateResult upsert();
+	}
+
 	/**
 	 * Declare the {@link Update} to apply.
 	 *
@@ -80,7 +156,7 @@ public interface ExecutableUpdateOperation {
 		 * @param replacement must not be {@literal null}.
 		 * @return new instance of {@link FindAndReplaceOptions}.
 		 * @throws IllegalArgumentException if options is {@literal null}.
-		 * 2.1
+		 * @since 2.1
 		 */
 		FindAndReplaceWithOptions<T> replaceWith(T replacement);
 	}
@@ -140,29 +216,6 @@ public interface ExecutableUpdateOperation {
 		TerminatingFindAndModify<T> withOptions(FindAndModifyOptions options);
 	}
 
-	/**
-	 * Trigger findAndModify execution by calling one of the terminating methods.
-	 */
-	interface TerminatingFindAndModify<T> {
-
-		/**
-		 * Find, modify and return the first matching document.
-		 *
-		 * @return {@link Optional#empty()} if nothing found.
-		 */
-		default Optional<T> findAndModify() {
-			return Optional.ofNullable(findAndModifyValue());
-		}
-
-		/**
-		 * Find, modify and return the first matching document.
-		 *
-		 * @return {@literal null} if nothing found.
-		 */
-		@Nullable
-		T findAndModifyValue();
-	}
-
 	/**
 	 * Define {@link FindAndReplaceOptions}.
 	 *
@@ -181,59 +234,6 @@ public interface ExecutableUpdateOperation {
 		TerminatingFindAndReplace<T> withOptions(FindAndReplaceOptions options);
 	}
 
-	/**
-	 * Trigger findAndReplace execution by calling one of the terminating methods.
-	 */
-	interface TerminatingFindAndReplace<T> {
-
-		/**
-		 * Find, replace and return the first matching document.
-		 *
-		 * @return {@link Optional#empty()} if nothing found.
-		 */
-		default Optional<T> findAndReplace() {
-			return Optional.ofNullable(findAndReplaceValue());
-		}
-
-		/**
-		 * Find, replace and return the first matching document.
-		 *
-		 * @return {@literal null} if nothing found.
-		 */
-		@Nullable
-		T findAndReplaceValue();
-	}
-
-	/**
-	 * Trigger update execution by calling one of the terminating methods.
-	 *
-	 * @author Christoph Strobl
-	 * @since 2.0
-	 */
-	interface TerminatingUpdate<T> extends TerminatingFindAndModify<T>, FindAndModifyWithOptions<T> {
-
-		/**
-		 * Update all matching documents in the collection.
-		 *
-		 * @return never {@literal null}.
-		 */
-		UpdateResult all();
-
-		/**
-		 * Update the first document in the collection.
-		 *
-		 * @return never {@literal null}.
-		 */
-		UpdateResult first();
-
-		/**
-		 * Creates a new document if no documents match the filter query or updates the matching ones.
-		 *
-		 * @return never {@literal null}.
-		 */
-		UpdateResult upsert();
-	}
-
 	/**
 	 * @author Christoph Strobl
 	 * @since 2.0

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/MongoTemplate.java

@@ -182,7 +182,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 	static {
 
-		Set<String> iterableClasses = new HashSet<String>();
+		Set<String> iterableClasses = new HashSet<>();
 		iterableClasses.add(List.class.getName());
 		iterableClasses.add(Collection.class.getName());
 		iterableClasses.add(Iterator.class.getName());
@@ -418,7 +418,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 				FindIterable<Document> cursor = new QueryCursorPreparer(query, entityType)
 						.prepare(collection.find(mappedQuery, Document.class).projection(mappedFields));
 
-				return new CloseableIterableCursorAdapter<T>(cursor, exceptionTranslator,
+				return new CloseableIterableCursorAdapter<>(cursor, exceptionTranslator,
 						new ProjectingReadCallback<>(mongoConverter, entityType, returnType, collectionName));
 			}
 		});
@@ -998,9 +998,9 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		List<Object> results = (List<Object>) commandResult.get("results");
 		results = results == null ? Collections.emptyList() : results;
 
-		DocumentCallback<GeoResult<T>> callback = new GeoNearResultDocumentCallback<T>(
+		DocumentCallback<GeoResult<T>> callback = new GeoNearResultDocumentCallback<>(
 				new ProjectingReadCallback<>(mongoConverter, domainType, returnType, collectionName), near.getMetric());
-		List<GeoResult<T>> result = new ArrayList<GeoResult<T>>(results.size());
+		List<GeoResult<T>> result = new ArrayList<>(results.size());
 
 		int index = 0;
 		long elementsToSkip = near.getSkip() != null ? near.getSkip() : 0;
@@ -1021,11 +1021,11 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 		if (elementsToSkip > 0) {
 			// as we skipped some elements we have to calculate the averageDistance ourselves:
-			return new GeoResults<T>(result, near.getMetric());
+			return new GeoResults<>(result, near.getMetric());
 		}
 
 		GeoCommandStatistics stats = GeoCommandStatistics.from(commandResult);
-		return new GeoResults<T>(result, new Distance(stats.getAverageDistance(), near.getMetric()));
+		return new GeoResults<>(result, new Distance(stats.getAverageDistance(), near.getMetric()));
 	}
 
 	@Nullable
@@ -1261,16 +1261,16 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 	protected <T> void doInsert(String collectionName, T objectToSave, MongoWriter<T> writer) {
 
 		initializeVersionProperty(objectToSave);
-		maybeEmitEvent(new BeforeConvertEvent<T>(objectToSave, collectionName));
+		maybeEmitEvent(new BeforeConvertEvent<>(objectToSave, collectionName));
 		assertUpdateableIdIfNotSet(objectToSave);
 
 		Document dbDoc = toDocument(objectToSave, writer);
 
-		maybeEmitEvent(new BeforeSaveEvent<T>(objectToSave, dbDoc, collectionName));
+		maybeEmitEvent(new BeforeSaveEvent<>(objectToSave, dbDoc, collectionName));
 		Object id = insertDocument(collectionName, dbDoc, objectToSave.getClass());
 
 		populateIdIfNecessary(objectToSave, id);
-		maybeEmitEvent(new AfterSaveEvent<T>(objectToSave, dbDoc, collectionName));
+		maybeEmitEvent(new AfterSaveEvent<>(objectToSave, dbDoc, collectionName));
 	}
 
 	/**
@@ -1343,7 +1343,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 	protected <T> void doInsertAll(Collection<? extends T> listToSave, MongoWriter<T> writer) {
 
-		Map<String, List<T>> elementsByCollection = new HashMap<String, List<T>>();
+		Map<String, List<T>> elementsByCollection = new HashMap<>();
 
 		for (T element : listToSave) {
 
@@ -1357,7 +1357,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 			List<T> collectionElements = elementsByCollection.get(collection);
 
 			if (null == collectionElements) {
-				collectionElements = new ArrayList<T>();
+				collectionElements = new ArrayList<>();
 				elementsByCollection.put(collection, collectionElements);
 			}
 
@@ -1373,15 +1373,15 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 		Assert.notNull(writer, "MongoWriter must not be null!");
 
-		List<Document> documentList = new ArrayList<Document>();
+		List<Document> documentList = new ArrayList<>();
 		for (T o : batchToSave) {
 
 			initializeVersionProperty(o);
-			maybeEmitEvent(new BeforeConvertEvent<T>(o, collectionName));
+			maybeEmitEvent(new BeforeConvertEvent<>(o, collectionName));
 
 			Document document = toDocument(o, writer);
 
-			maybeEmitEvent(new BeforeSaveEvent<T>(o, document, collectionName));
+			maybeEmitEvent(new BeforeSaveEvent<>(o, document, collectionName));
 			documentList.add(document);
 		}
 
@@ -1391,7 +1391,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		for (T obj : batchToSave) {
 			if (i < ids.size()) {
 				populateIdIfNecessary(obj, ids.get(i));
-				maybeEmitEvent(new AfterSaveEvent<T>(obj, documentList.get(i), collectionName));
+				maybeEmitEvent(new AfterSaveEvent<>(obj, documentList.get(i), collectionName));
 			}
 			i++;
 		}
@@ -1433,14 +1433,14 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 			// Bump version number
 			convertingAccessor.setProperty(property, number.longValue() + 1);
 
-			maybeEmitEvent(new BeforeConvertEvent<T>(objectToSave, collectionName));
+			maybeEmitEvent(new BeforeConvertEvent<>(objectToSave, collectionName));
 			assertUpdateableIdIfNotSet(objectToSave);
 
 			Document document = new Document();
 
 			this.mongoConverter.write(objectToSave, document);
 
-			maybeEmitEvent(new BeforeSaveEvent<T>(objectToSave, document, collectionName));
+			maybeEmitEvent(new BeforeSaveEvent<>(objectToSave, document, collectionName));
 			Update update = Update.fromDocument(document, ID_FIELD);
 
 			// Create query for entity with the id and old version
@@ -1455,7 +1455,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 						String.format("Cannot save entity %s with version %s to collection %s. Has it been modified meanwhile?", id,
 								number, collectionName));
 			}
-			maybeEmitEvent(new AfterSaveEvent<T>(objectToSave, document, collectionName));
+			maybeEmitEvent(new AfterSaveEvent<>(objectToSave, document, collectionName));
 
 			return objectToSave;
 		}
@@ -1466,16 +1466,16 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 	protected <T> T doSave(String collectionName, T objectToSave, MongoWriter<T> writer) {
 
-		maybeEmitEvent(new BeforeConvertEvent<T>(objectToSave, collectionName));
+		maybeEmitEvent(new BeforeConvertEvent<>(objectToSave, collectionName));
 		assertUpdateableIdIfNotSet(objectToSave);
 
 		Document dbDoc = toDocument(objectToSave, writer);
 
-		maybeEmitEvent(new BeforeSaveEvent<T>(objectToSave, dbDoc, collectionName));
+		maybeEmitEvent(new BeforeSaveEvent<>(objectToSave, dbDoc, collectionName));
 		Object id = saveDocument(collectionName, dbDoc, objectToSave.getClass());
 
 		populateIdIfNecessary(objectToSave, id);
-		maybeEmitEvent(new AfterSaveEvent<T>(objectToSave, dbDoc, collectionName));
+		maybeEmitEvent(new AfterSaveEvent<>(objectToSave, dbDoc, collectionName));
 
 		return objectToSave;
 	}
@@ -1757,7 +1757,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		Iterator<?> it = objects.iterator();
 		Pair<String, Object> pair = extractIdPropertyAndValue(it.next());
 
-		ArrayList<Object> ids = new ArrayList<Object>(objects.size());
+		ArrayList<Object> ids = new ArrayList<>(objects.size());
 		ids.add(pair.getSecond());
 
 		while (it.hasNext()) {
@@ -1819,7 +1819,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 			public DeleteResult doInCollection(MongoCollection<Document> collection)
 					throws MongoException, DataAccessException {
 
-				maybeEmitEvent(new BeforeDeleteEvent<T>(queryObject, entityClass, collectionName));
+				maybeEmitEvent(new BeforeDeleteEvent<>(queryObject, entityClass, collectionName));
 
 				Document removeQuery = queryObject;
 
@@ -1855,7 +1855,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 				DeleteResult result = multi ? collectionToUse.deleteMany(removeQuery, options)
 						: collection.deleteOne(removeQuery, options);
 
-				maybeEmitEvent(new AfterDeleteEvent<T>(queryObject, entityClass, collectionName));
+				maybeEmitEvent(new AfterDeleteEvent<>(queryObject, entityClass, collectionName));
 
 				return result;
 			}
@@ -1870,7 +1870,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 	@Override
 	public <T> List<T> findAll(Class<T> entityClass, String collectionName) {
 		return executeFindMultiInternal(new FindCallback(new Document(), new Document()), null,
-				new ReadDocumentCallback<T>(mongoConverter, entityClass, collectionName), collectionName);
+				new ReadDocumentCallback<>(mongoConverter, entityClass, collectionName), collectionName);
 	}
 
 	@Override
@@ -2032,14 +2032,14 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 		@SuppressWarnings("unchecked")
 		Iterable<Document> resultSet = (Iterable<Document>) commandResult.get("retval");
-		List<T> mappedResults = new ArrayList<T>();
-		DocumentCallback<T> callback = new ReadDocumentCallback<T>(mongoConverter, entityClass, inputCollectionName);
+		List<T> mappedResults = new ArrayList<>();
+		DocumentCallback<T> callback = new ReadDocumentCallback<>(mongoConverter, entityClass, inputCollectionName);
 
 		for (Document resultDocument : resultSet) {
 			mappedResults.add(callback.doWith(resultDocument));
 		}
 
-		return new GroupByResults<T>(mappedResults, commandResult);
+		return new GroupByResults<>(mappedResults, commandResult);
 	}
 
 	/* (non-Javadoc)
@@ -2359,7 +2359,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 	public Set<String> getCollectionNames() {
 		return execute(new DbCallback<Set<String>>() {
 			public Set<String> doInDB(MongoDatabase db) throws MongoException, DataAccessException {
-				Set<String> result = new LinkedHashSet<String>();
+				Set<String> result = new LinkedHashSet<>();
 				for (String name : db.listCollectionNames()) {
 					result.add(name);
 				}
@@ -2465,7 +2465,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		}
 
 		return executeFindOneInternal(new FindOneCallback(mappedQuery, mappedFields),
-				new ReadDocumentCallback<T>(this.mongoConverter, entityClass, collectionName), collectionName);
+				new ReadDocumentCallback<>(this.mongoConverter, entityClass, collectionName), collectionName);
 	}
 
 	/**
@@ -2480,7 +2480,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 	 */
 	protected <T> List<T> doFind(String collectionName, Document query, Document fields, Class<T> entityClass) {
 		return doFind(collectionName, query, fields, entityClass, null,
-				new ReadDocumentCallback<T>(this.mongoConverter, entityClass, collectionName));
+				new ReadDocumentCallback<>(this.mongoConverter, entityClass, collectionName));
 	}
 
 	/**
@@ -2499,7 +2499,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 	protected <T> List<T> doFind(String collectionName, Document query, Document fields, Class<T> entityClass,
 			CursorPreparer preparer) {
 		return doFind(collectionName, query, fields, entityClass, preparer,
-				new ReadDocumentCallback<T>(mongoConverter, entityClass, collectionName));
+				new ReadDocumentCallback<>(mongoConverter, entityClass, collectionName));
 	}
 
 	protected <S, T> List<T> doFind(String collectionName, Document query, Document fields, Class<S> entityClass,
@@ -2631,7 +2631,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 		return executeFindOneInternal(
 				new FindAndRemoveCallback(queryMapper.getMappedObject(query, entity), fields, sort, collation),
-				new ReadDocumentCallback<T>(readerToUse, entityClass, collectionName), collectionName);
+				new ReadDocumentCallback<>(readerToUse, entityClass, collectionName), collectionName);
 	}
 
 	protected <T> T doFindAndModify(String collectionName, Document query, Document fields, Document sort,
@@ -2658,7 +2658,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		}
 
 		return executeFindOneInternal(new FindAndModifyCallback(mappedQuery, fields, sort, mappedUpdate, options),
-				new ReadDocumentCallback<T>(readerToUse, entityClass, collectionName), collectionName);
+				new ReadDocumentCallback<>(readerToUse, entityClass, collectionName), collectionName);
 	}
 
 	protected <T> T doFindAndReplace(String collectionName, Document query, Document fields, Document sort,
@@ -2684,7 +2684,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		maybeEmitEvent(new BeforeSaveEvent<>(replacement, dbDoc, collectionName));
 
 		return executeFindOneInternal(new FindAndReplaceCallback(mappedQuery, fields, sort, dbDoc, options),
-				new ReadDocumentCallback<T>(readerToUse, entityClass, collectionName), collectionName);
+				new ReadDocumentCallback<>(readerToUse, entityClass, collectionName), collectionName);
 	}
 
 	/**
@@ -2795,7 +2795,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 
 				cursor = iterable.iterator();
 
-				List<T> result = new ArrayList<T>();
+				List<T> result = new ArrayList<>();
 
 				while (cursor.hasNext()) {
 					Document object = cursor.next();
@@ -3168,13 +3168,13 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 		public T doWith(@Nullable Document object) {
 
 			if (null != object) {
-				maybeEmitEvent(new AfterLoadEvent<T>(object, type, collectionName));
+				maybeEmitEvent(new AfterLoadEvent<>(object, type, collectionName));
 			}
 
 			T source = reader.read(type, object);
 
 			if (null != source) {
-				maybeEmitEvent(new AfterConvertEvent<T>(object, source, collectionName));
+				maybeEmitEvent(new AfterConvertEvent<>(object, source, collectionName));
 			}
 
 			return source;
@@ -3213,7 +3213,7 @@ public class MongoTemplate implements MongoOperations, ApplicationContextAware,
 					: targetType;
 
 			if (null != object) {
-				maybeEmitEvent(new AfterLoadEvent<T>(object, targetType, collectionName));
+				maybeEmitEvent(new AfterLoadEvent<>(object, targetType, collectionName));
 			}
 
 			Object source = reader.read(typeToRead, object);

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/ReactiveMongoTemplate.java

@@ -114,40 +114,13 @@ import org.springframework.util.ObjectUtils;
 import org.springframework.util.ResourceUtils;
 import org.springframework.util.StringUtils;
 
-import com.mongodb.BasicDBObject;
-import com.mongodb.ClientSessionOptions;
-import com.mongodb.CursorType;
-import com.mongodb.DBCollection;
-import com.mongodb.DBCursor;
-import com.mongodb.DBRef;
-import com.mongodb.Mongo;
-import com.mongodb.MongoException;
-import com.mongodb.ReadPreference;
-import com.mongodb.WriteConcern;
-import com.mongodb.client.model.CountOptions;
-import com.mongodb.client.model.CreateCollectionOptions;
-import com.mongodb.client.model.DeleteOptions;
-import com.mongodb.client.model.Filters;
-import com.mongodb.client.model.FindOneAndDeleteOptions;
-import com.mongodb.client.model.FindOneAndReplaceOptions;
-import com.mongodb.client.model.FindOneAndUpdateOptions;
-import com.mongodb.client.model.ReplaceOptions;
-import com.mongodb.client.model.ReturnDocument;
-import com.mongodb.client.model.UpdateOptions;
-import com.mongodb.client.model.ValidationOptions;
+import com.mongodb.*;
+import com.mongodb.client.model.*;
 import com.mongodb.client.model.changestream.FullDocument;
 import com.mongodb.client.result.DeleteResult;
 import com.mongodb.client.result.UpdateResult;
-import com.mongodb.reactivestreams.client.AggregatePublisher;
-import com.mongodb.reactivestreams.client.ChangeStreamPublisher;
-import com.mongodb.reactivestreams.client.ClientSession;
-import com.mongodb.reactivestreams.client.DistinctPublisher;
-import com.mongodb.reactivestreams.client.FindPublisher;
-import com.mongodb.reactivestreams.client.MapReducePublisher;
+import com.mongodb.reactivestreams.client.*;
 import com.mongodb.reactivestreams.client.MongoClient;
-import com.mongodb.reactivestreams.client.MongoCollection;
-import com.mongodb.reactivestreams.client.MongoDatabase;
-import com.mongodb.reactivestreams.client.Success;
 import com.mongodb.util.JSONParseException;
 
 /**
@@ -713,7 +686,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 	 */
 	public Mono<Void> dropCollection(final String collectionName) {
 
-		return createMono(collectionName, collection -> collection.drop()).doOnSuccess(success -> {
+		return createMono(collectionName, MongoCollection::drop).doOnSuccess(success -> {
 			if (LOGGER.isDebugEnabled()) {
 				LOGGER.debug("Dropped collection [" + collectionName + "]");
 			}
@@ -1051,7 +1024,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 						entityClass, collectionName);
 			}
 
-			GeoNearResultDbObjectCallback<T> callback = new GeoNearResultDbObjectCallback<T>(
+			GeoNearResultDbObjectCallback<T> callback = new GeoNearResultDbObjectCallback<>(
 					new ProjectingReadCallback<>(mongoConverter, entityClass, returnType, collectionName), near.getMetric());
 
 			return executeCommand(command, this.readPreference).flatMapMany(document -> {
@@ -1291,15 +1264,15 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 		return Mono.defer(() -> {
 
 			initializeVersionProperty(objectToSave);
-			maybeEmitEvent(new BeforeConvertEvent<T>(objectToSave, collectionName));
+			maybeEmitEvent(new BeforeConvertEvent<>(objectToSave, collectionName));
 
-			Document dbDoc = toDbObject(objectToSave, writer);
+			Document dbDoc = toDocument(objectToSave, writer);
 
-			maybeEmitEvent(new BeforeSaveEvent<T>(objectToSave, dbDoc, collectionName));
+			maybeEmitEvent(new BeforeSaveEvent<>(objectToSave, dbDoc, collectionName));
 
 			Mono<T> afterInsert = insertDBObject(collectionName, dbDoc, objectToSave.getClass()).flatMap(id -> {
 				populateIdIfNecessary(objectToSave, id);
-				maybeEmitEvent(new AfterSaveEvent<T>(objectToSave, dbDoc, collectionName));
+				maybeEmitEvent(new AfterSaveEvent<>(objectToSave, dbDoc, collectionName));
 				return Mono.just(objectToSave);
 			});
 
@@ -1342,18 +1315,14 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 
 	protected <T> Flux<T> doInsertAll(Collection<? extends T> listToSave, MongoWriter<Object> writer) {
 
-		final Map<String, List<T>> elementsByCollection = new HashMap<String, List<T>>();
+		final Map<String, List<T>> elementsByCollection = new HashMap<>();
 
 		listToSave.forEach(element -> {
+
 			MongoPersistentEntity<?> entity = mappingContext.getRequiredPersistentEntity(element.getClass());
 
 			String collection = entity.getCollection();
-			List<T> collectionElements = elementsByCollection.get(collection);
-
-			if (null == collectionElements) {
-				collectionElements = new ArrayList<T>();
-				elementsByCollection.put(collection, collectionElements);
-			}
+			List<T> collectionElements = elementsByCollection.computeIfAbsent(collection, k -> new ArrayList<>());
 
 			collectionElements.add(element);
 		});
@@ -1373,11 +1342,11 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 					public Flux<Tuple2<T, Document>> apply(T o) {
 
 						initializeVersionProperty(o);
-						maybeEmitEvent(new BeforeConvertEvent<T>(o, collectionName));
+						maybeEmitEvent(new BeforeConvertEvent<>(o, collectionName));
 
-						Document dbDoc = toDbObject(o, writer);
+						Document dbDoc = toDocument(o, writer);
 
-						maybeEmitEvent(new BeforeSaveEvent<T>(o, dbDoc, collectionName));
+						maybeEmitEvent(new BeforeSaveEvent<>(o, dbDoc, collectionName));
 						return Flux.zip(Mono.just(o), Mono.just(dbDoc));
 					}
 				}).collectList();
@@ -1392,7 +1361,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 		return insertDocuments.map(tuple -> {
 
 			populateIdIfNecessary(tuple.getT1(), tuple.getT2().get(ID_FIELD));
-			maybeEmitEvent(new AfterSaveEvent<T>(tuple.getT1(), tuple.getT2(), collectionName));
+			maybeEmitEvent(new AfterSaveEvent<>(tuple.getT1(), tuple.getT2(), collectionName));
 			return tuple.getT1();
 		});
 	}
@@ -1480,16 +1449,16 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 			// Bump version number
 			convertingAccessor.setProperty(versionProperty, versionNumber.longValue() + 1);
 
-			ReactiveMongoTemplate.this.maybeEmitEvent(new BeforeConvertEvent<T>(objectToSave, collectionName));
+			ReactiveMongoTemplate.this.maybeEmitEvent(new BeforeConvertEvent<>(objectToSave, collectionName));
 
-			Document document = ReactiveMongoTemplate.this.toDbObject(objectToSave, mongoConverter);
+			Document document = ReactiveMongoTemplate.this.toDocument(objectToSave, mongoConverter);
 
-			ReactiveMongoTemplate.this.maybeEmitEvent(new BeforeSaveEvent<T>(objectToSave, document, collectionName));
+			ReactiveMongoTemplate.this.maybeEmitEvent(new BeforeSaveEvent<>(objectToSave, document, collectionName));
 			Update update = Update.fromDocument(document, ID_FIELD);
 
 			return doUpdate(collectionName, query, update, objectToSave.getClass(), false, false).map(updateResult -> {
 
-				maybeEmitEvent(new AfterSaveEvent<T>(objectToSave, document, collectionName));
+				maybeEmitEvent(new AfterSaveEvent<>(objectToSave, document, collectionName));
 				return objectToSave;
 			});
 		});
@@ -1501,14 +1470,14 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 
 		return createMono(collectionName, collection -> {
 
-			maybeEmitEvent(new BeforeConvertEvent<T>(objectToSave, collectionName));
-			Document dbDoc = toDbObject(objectToSave, writer);
-			maybeEmitEvent(new BeforeSaveEvent<T>(objectToSave, dbDoc, collectionName));
+			maybeEmitEvent(new BeforeConvertEvent<>(objectToSave, collectionName));
+			Document dbDoc = toDocument(objectToSave, writer);
+			maybeEmitEvent(new BeforeSaveEvent<>(objectToSave, dbDoc, collectionName));
 
 			return saveDocument(collectionName, dbDoc, objectToSave.getClass()).map(id -> {
 
 				populateIdIfNecessary(objectToSave, id);
-				maybeEmitEvent(new AfterSaveEvent<T>(objectToSave, dbDoc, collectionName));
+				maybeEmitEvent(new AfterSaveEvent<>(objectToSave, dbDoc, collectionName));
 				return objectToSave;
 			});
 		});
@@ -1853,7 +1822,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 		Iterator<?> it = objects.iterator();
 		Pair<String, Object> firstEntry = extractIdPropertyAndValue(it.next());
 
-		ArrayList<Object> ids = new ArrayList<Object>(objects.size());
+		ArrayList<Object> ids = new ArrayList<>(objects.size());
 		ids.add(firstEntry.getSecond());
 
 		while (it.hasNext()) {
@@ -1923,7 +1892,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 
 			Document removeQuey = queryMapper.getMappedObject(queryObject, entity);
 
-			maybeEmitEvent(new BeforeDeleteEvent<T>(removeQuey, entityClass, collectionName));
+			maybeEmitEvent(new BeforeDeleteEvent<>(removeQuey, entityClass, collectionName));
 
 			MongoAction mongoAction = new MongoAction(writeConcern, MongoActionOperation.REMOVE, collectionName, entityClass,
 					null, removeQuey);
@@ -1955,7 +1924,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 				return collectionToUse.deleteMany(removeQuey, deleteOptions);
 			}
 
-		}).doOnNext(deleteResult -> maybeEmitEvent(new AfterDeleteEvent<T>(queryObject, entityClass, collectionName)))
+		}).doOnNext(deleteResult -> maybeEmitEvent(new AfterDeleteEvent<>(queryObject, entityClass, collectionName)))
 				.next();
 	}
 
@@ -1973,7 +1942,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 	 */
 	public <T> Flux<T> findAll(Class<T> entityClass, String collectionName) {
 		return executeFindMultiInternal(new FindCallback(null), null,
-				new ReadDocumentCallback<T>(mongoConverter, entityClass, collectionName), collectionName);
+				new ReadDocumentCallback<>(mongoConverter, entityClass, collectionName), collectionName);
 	}
 
 	/*
@@ -1981,6 +1950,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 	 * @see org.springframework.data.mongodb.core.ReactiveMongoOperations#findAllAndRemove(org.springframework.data.mongodb.core.query.Query, java.lang.String)
 	 */
 	@Override
+	@SuppressWarnings("unchecked")
 	public <T> Flux<T> findAllAndRemove(Query query, String collectionName) {
 		return (Flux<T>) findAllAndRemove(query, Object.class, collectionName);
 	}
@@ -2026,7 +1996,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 
 			return executeFindMultiInternal(
 					collection -> new FindCallback(null).doInCollection(collection).cursorType(CursorType.TailableAwait), null,
-					new ReadDocumentCallback<T>(mongoConverter, entityClass, collectionName), collectionName);
+					new ReadDocumentCallback<>(mongoConverter, entityClass, collectionName), collectionName);
 		}
 
 		return doFind(collectionName, query.getQueryObject(), query.getFieldsObject(), entityClass,
@@ -2311,7 +2281,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 		}
 
 		return executeFindOneInternal(new FindOneCallback(mappedQuery, mappedFields, collation),
-				new ReadDocumentCallback<T>(this.mongoConverter, entityClass, collectionName), collectionName);
+				new ReadDocumentCallback<>(this.mongoConverter, entityClass, collectionName), collectionName);
 	}
 
 	/**
@@ -2326,7 +2296,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 	 */
 	protected <T> Flux<T> doFind(String collectionName, Document query, Document fields, Class<T> entityClass) {
 		return doFind(collectionName, query, fields, entityClass, null,
-				new ReadDocumentCallback<T>(this.mongoConverter, entityClass, collectionName));
+				new ReadDocumentCallback<>(this.mongoConverter, entityClass, collectionName));
 	}
 
 	/**
@@ -2345,7 +2315,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 	protected <T> Flux<T> doFind(String collectionName, Document query, Document fields, Class<T> entityClass,
 			FindPublisherPreparer preparer) {
 		return doFind(collectionName, query, fields, entityClass, preparer,
-				new ReadDocumentCallback<T>(mongoConverter, entityClass, collectionName));
+				new ReadDocumentCallback<>(mongoConverter, entityClass, collectionName));
 	}
 
 	protected <S, T> Flux<T> doFind(String collectionName, Document query, Document fields, Class<S> entityClass,
@@ -2484,7 +2454,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 
 		return executeFindOneInternal(
 				new FindAndRemoveCallback(queryMapper.getMappedObject(query, entity), fields, sort, collation),
-				new ReadDocumentCallback<T>(this.mongoConverter, entityClass, collectionName), collectionName);
+				new ReadDocumentCallback<>(this.mongoConverter, entityClass, collectionName), collectionName);
 	}
 
 	protected <T> Mono<T> doFindAndModify(String collectionName, Document query, Document fields, Document sort,
@@ -2507,7 +2477,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 			}
 
 			return executeFindOneInternal(new FindAndModifyCallback(mappedQuery, fields, sort, mappedUpdate, options),
-					new ReadDocumentCallback<T>(this.mongoConverter, entityClass, collectionName), collectionName);
+					new ReadDocumentCallback<>(this.mongoConverter, entityClass, collectionName), collectionName);
 		});
 	}
 
@@ -2519,7 +2489,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 		return Mono.defer(() -> {
 
 			Document mappedQuery = queryMapper.getMappedObject(query, entity);
-			Document dbDoc = toDbObject(replacement, this.mongoConverter);
+			Document dbDoc = toDocument(replacement, this.mongoConverter);
 
 			if (LOGGER.isDebugEnabled()) {
 				LOGGER.debug(
@@ -2532,7 +2502,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 			maybeEmitEvent(new BeforeSaveEvent<>(replacement, dbDoc, collectionName));
 
 			return executeFindOneInternal(new FindAndReplaceCallback(mappedQuery, fields, sort, dbDoc, options),
-					new ReadDocumentCallback<T>(this.mongoConverter, entityClass, collectionName), collectionName);
+					new ReadDocumentCallback<>(this.mongoConverter, entityClass, collectionName), collectionName);
 		});
 	}
 
@@ -2592,16 +2562,9 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 
 	protected void ensureNotIterable(Object o) {
 
-		boolean isIterable = o.getClass().isArray();
-
-		if (!isIterable) {
-			for (Class iterableClass : ITERABLE_CLASSES) {
-				if (iterableClass.isAssignableFrom(o.getClass()) || o.getClass().getName().equals(iterableClass.getName())) {
-					isIterable = true;
-					break;
-				}
-			}
-		}
+		boolean isIterable = o.getClass().isArray()
+				|| ITERABLE_CLASSES.stream().anyMatch(iterableClass -> iterableClass.isAssignableFrom(o.getClass())
+						|| o.getClass().getName().equals(iterableClass.getName()));
 
 		if (isIterable) {
 			throw new IllegalArgumentException("Cannot use a collection here.");
@@ -2820,7 +2783,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 	 * @param writer
 	 * @return
 	 */
-	private <T> Document toDbObject(T objectToSave, MongoWriter<T> writer) {
+	private <T> Document toDocument(T objectToSave, MongoWriter<T> writer) {
 
 		if (objectToSave instanceof Document) {
 			return (Document) objectToSave;
@@ -3128,11 +3091,11 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 		public T doWith(@Nullable Document object) {
 
 			if (null != object) {
-				maybeEmitEvent(new AfterLoadEvent<T>(object, type, collectionName));
+				maybeEmitEvent(new AfterLoadEvent<>(object, type, collectionName));
 			}
 			T source = reader.read(type, object);
 			if (null != source) {
-				maybeEmitEvent(new AfterConvertEvent<T>(object, source, collectionName));
+				maybeEmitEvent(new AfterConvertEvent<>(object, source, collectionName));
 			}
 			return source;
 		}
@@ -3212,7 +3175,7 @@ public class ReactiveMongoTemplate implements ReactiveMongoOperations, Applicati
 
 			T doWith = delegate.doWith(content);
 
-			return new GeoResult<T>(doWith, new Distance(distance, metric));
+			return new GeoResult<>(doWith, new Distance(distance, metric));
 		}
 	}
 

spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/ReactiveMongoTemplateTests.java

@@ -15,11 +15,10 @@
  */
 package org.springframework.data.mongodb.core;
 
-import static org.hamcrest.Matchers.*;
-import static org.junit.Assert.*;
 import static org.springframework.data.mongodb.core.aggregation.Aggregation.*;
 import static org.springframework.data.mongodb.core.query.Criteria.*;
 import static org.springframework.data.mongodb.core.query.Query.*;
+import static org.springframework.data.mongodb.test.util.Assertions.*;
 
 import lombok.Data;
 import reactor.core.Disposable;
@@ -119,7 +118,7 @@ public class ReactiveMongoTemplateTests {
 
 		StepVerifier.create(template.insert(person)).expectNextCount(1).verifyComplete();
 
-		assertThat(person.getId(), is(notNullValue()));
+		assertThat(person.getId()).isNotNull();
 	}
 
 	@Test // DATAMONGO-1444
@@ -129,7 +128,7 @@ public class ReactiveMongoTemplateTests {
 
 		StepVerifier.create(template.insertAll(Collections.singleton(person))).expectNextCount(1).verifyComplete();
 
-		assertThat(person.getId(), is(notNullValue()));
+		assertThat(person.getId()).isNotNull();
 	}
 
 	@Test // DATAMONGO-1444
@@ -140,7 +139,7 @@ public class ReactiveMongoTemplateTests {
 		StepVerifier.create(template.insert(Collections.singleton(person), PersonWithAList.class)).expectNextCount(1)
 				.verifyComplete();
 
-		assertThat(person.getId(), is(notNullValue()));
+		assertThat(person.getId()).isNotNull();
 	}
 
 	@Test // DATAMONGO-1444
@@ -151,7 +150,7 @@ public class ReactiveMongoTemplateTests {
 
 		StepVerifier.create(template.save(person)).expectNextCount(1).verifyComplete();
 
-		assertThat(person.getId(), is(notNullValue()));
+		assertThat(person.getId()).isNotNull();
 	}
 
 	@Test // DATAMONGO-1444
@@ -244,7 +243,7 @@ public class ReactiveMongoTemplateTests {
 
 		StepVerifier.create(template.findOne(query, PersonWithAList.class)).consumeNextWith(actual -> {
 
-			assertThat(actual.getWishList().size(), is(0));
+			assertThat(actual.getWishList()).isEmpty();
 		}).verifyComplete();
 
 		person.addToWishList("please work!");
@@ -253,7 +252,7 @@ public class ReactiveMongoTemplateTests {
 
 		StepVerifier.create(template.findOne(query, PersonWithAList.class)).consumeNextWith(actual -> {
 
-			assertThat(actual.getWishList().size(), is(1));
+			assertThat(actual.getWishList()).hasSize(1);
 		}).verifyComplete();
 
 		Friend friend = new Friend();
@@ -265,8 +264,8 @@ public class ReactiveMongoTemplateTests {
 
 		StepVerifier.create(template.findOne(query, PersonWithAList.class)).consumeNextWith(actual -> {
 
-			assertThat(actual.getWishList().size(), is(1));
-			assertThat(actual.getFriends().size(), is(1));
+			assertThat(actual.getWishList()).hasSize(1);
+			assertThat(actual.getFriends()).hasSize(1);
 		}).verifyComplete();
 	}
 
@@ -285,7 +284,7 @@ public class ReactiveMongoTemplateTests {
 
 		StepVerifier.create(template.findOne(query, PersonWithAList.class)).consumeNextWith(actual -> {
 
-			assertThat(actual.getFirstName(), is("Mark"));
+			assertThat(actual.getFirstName()).isEqualTo("Mark");
 		}).verifyComplete();
 	}
 
@@ -315,7 +314,7 @@ public class ReactiveMongoTemplateTests {
 						.flatMapMany(p -> template.find(new Query(where("age").is(25)), Person.class)))
 				.consumeNextWith(actual -> {
 
-					assertThat(actual.getFirstName(), is(equalTo("Sven")));
+					assertThat(actual.getFirstName()).isEqualTo("Sven");
 				}).verifyComplete();
 	}
 
@@ -329,7 +328,7 @@ public class ReactiveMongoTemplateTests {
 						.flatMapMany(p -> template.find(new Query(where("age").is(25)), Person.class, "people")))
 				.consumeNextWith(actual -> {
 
-					assertThat(actual.getFirstName(), is(equalTo("Sven")));
+					assertThat(actual.getFirstName()).isEqualTo("Sven");
 				}).verifyComplete();
 	}
 
@@ -431,29 +430,29 @@ public class ReactiveMongoTemplateTests {
 		Update update = new Update().inc("age", 1);
 
 		Person p = template.findAndModify(query, update, Person.class).block(); // return old
-		assertThat(p.getFirstName(), is("Harry"));
-		assertThat(p.getAge(), is(23));
+		assertThat(p.getFirstName()).isEqualTo("Harry");
+		assertThat(p.getAge()).isEqualTo(23);
 		p = template.findOne(query, Person.class).block();
-		assertThat(p.getAge(), is(24));
+		assertThat(p.getAge()).isEqualTo(24);
 
 		p = template.findAndModify(query, update, Person.class, "person").block();
-		assertThat(p.getAge(), is(24));
+		assertThat(p.getAge()).isEqualTo(24);
 		p = template.findOne(query, Person.class).block();
-		assertThat(p.getAge(), is(25));
+		assertThat(p.getAge()).isEqualTo(25);
 
 		p = template.findAndModify(query, update, new FindAndModifyOptions().returnNew(true), Person.class).block();
-		assertThat(p.getAge(), is(26));
+		assertThat(p.getAge()).isEqualTo(26);
 
 		p = template.findAndModify(query, update, null, Person.class, "person").block();
-		assertThat(p.getAge(), is(26));
+		assertThat(p.getAge()).isEqualTo(26);
 		p = template.findOne(query, Person.class).block();
-		assertThat(p.getAge(), is(27));
+		assertThat(p.getAge()).isEqualTo(27);
 
 		Query query2 = new Query(where("firstName").is("Mary"));
 		p = template.findAndModify(query2, update, new FindAndModifyOptions().returnNew(true).upsert(true), Person.class)
 				.block();
-		assertThat(p.getFirstName(), is("Mary"));
-		assertThat(p.getAge(), is(1));
+		assertThat(p.getFirstName()).isEqualTo("Mary");
+		assertThat(p.getAge()).isEqualTo(1);
 	}
 
 	@Test // DATAMONGO-1827
@@ -468,7 +467,7 @@ public class ReactiveMongoTemplateTests {
 						org.bson.Document.class, "findandreplace") //
 				.as(StepVerifier::create) //
 				.consumeNextWith(actual -> {
-					assertThat(actual, hasEntry("foo", "bar"));
+					assertThat(actual).containsEntry("foo", "bar");
 				}).verifyComplete();
 
 		template.findOne(query(where("foo").is("baz")), org.bson.Document.class, "findandreplace") //
@@ -486,7 +485,7 @@ public class ReactiveMongoTemplateTests {
 		template.findAndReplace(query(where("name").is("Walter")), new MyPerson("Heisenberg")) //
 				.as(StepVerifier::create) //
 				.consumeNextWith(actual -> {
-					assertThat(actual.getName(), is("Walter"));
+					assertThat(actual.getName()).isEqualTo("Walter");
 				}).verifyComplete();
 
 		template.findOne(query(where("name").is("Heisenberg")), MyPerson.class) //
@@ -504,7 +503,7 @@ public class ReactiveMongoTemplateTests {
 						FindAndReplaceOptions.options().returnNew(true))
 				.as(StepVerifier::create) //
 				.consumeNextWith(actual -> {
-					assertThat(actual.getName(), is("Heisenberg"));
+					assertThat(actual.getName()).isEqualTo("Heisenberg");
 				}).verifyComplete();
 	}
 
@@ -617,7 +616,7 @@ public class ReactiveMongoTemplateTests {
 
 		StepVerifier.create(template.findAll(PersonWithVersionPropertyOfTypeInteger.class)).consumeNextWith(actual -> {
 
-			assertThat(actual.version, is(0));
+			assertThat(actual.version).isZero();
 		}).verifyComplete();
 
 		StepVerifier.create(template.findAll(PersonWithVersionPropertyOfTypeInteger.class).flatMap(p -> {
@@ -627,11 +626,11 @@ public class ReactiveMongoTemplateTests {
 			return template.save(person);
 		})).expectNextCount(1).verifyComplete();
 
-		assertThat(person.version, is(1));
+		assertThat(person.version).isOne();
 
 		StepVerifier.create(template.findAll(PersonWithVersionPropertyOfTypeInteger.class)).consumeNextWith(actual -> {
 
-			assertThat(actual.version, is(1));
+			assertThat(actual.version).isOne();
 		}).verifyComplete();
 
 		// Optimistic lock exception
@@ -697,7 +696,7 @@ public class ReactiveMongoTemplateTests {
 
 		StepVerifier.create(template.save(dbObject, "collection")).expectNextCount(1).verifyComplete();
 
-		assertThat(dbObject.containsKey("_id"), is(true));
+		assertThat(dbObject.containsKey("_id")).isTrue();
 	}
 
 	@Test(expected = MappingException.class) // DATAMONGO-1444, DATAMONGO-1730
@@ -721,8 +720,8 @@ public class ReactiveMongoTemplateTests {
 		StepVerifier.create(template.findById(dbObject.get("_id"), Document.class, "collection")) //
 				.consumeNextWith(actual -> {
 
-					assertThat(actual.get("foo"), is(dbObject.get("foo")));
-					assertThat(actual.get("_id"), is(dbObject.get("_id")));
+					assertThat(actual.get("foo")).isEqualTo(dbObject.get("foo"));
+					assertThat(actual.get("_id")).isEqualTo(dbObject.get("_id"));
 				}).verifyComplete();
 	}
 
@@ -776,7 +775,7 @@ public class ReactiveMongoTemplateTests {
 
 		StepVerifier.create(template.insert(person)).expectNextCount(1).verifyComplete();
 
-		assertThat(person.version, is(0));
+		assertThat(person.version).isZero();
 	}
 
 	@Test // DATAMONGO-1444
@@ -787,7 +786,7 @@ public class ReactiveMongoTemplateTests {
 
 		StepVerifier.create(template.insertAll(Collections.singleton(person))).expectNextCount(1).verifyComplete();
 
-		assertThat(person.version, is(0));
+		assertThat(person.version).isZero();
 	}
 
 	@Test // DATAMONGO-1444
@@ -805,10 +804,10 @@ public class ReactiveMongoTemplateTests {
 		person.firstName = "Dave";
 
 		StepVerifier.create(template.save(person, "personX")).expectNextCount(1).verifyComplete();
-		assertThat(person.version, is(0));
+		assertThat(person.version).isZero();
 
 		StepVerifier.create(template.save(person, "personX")).expectNextCount(1).verifyComplete();
-		assertThat(person.version, is(1));
+		assertThat(person.version).isOne();
 	}
 
 	@Test // DATAMONGO-1444
@@ -818,7 +817,7 @@ public class ReactiveMongoTemplateTests {
 		person.firstName = "Dave";
 
 		StepVerifier.create(template.save(person, "personX")).expectNextCount(1).verifyComplete();
-		assertThat(person.version, is(0L));
+		assertThat(person.version).isZero();
 	}
 
 	@Test // DATAMONGO-1444
@@ -852,7 +851,7 @@ public class ReactiveMongoTemplateTests {
 		person.firstName = "Dave";
 
 		StepVerifier.create(template.save(person)).expectNextCount(1).verifyComplete();
-		assertThat(person.version, is(0));
+		assertThat(person.version).isZero();
 
 		person.version = null;
 		StepVerifier.create(template.save(person)).expectError(DuplicateKeyException.class).verify();
@@ -881,7 +880,7 @@ public class ReactiveMongoTemplateTests {
 
 		StepVerifier.create(template.save(person)).expectNextCount(1).verifyComplete();
 
-		assertThat(person.id, is(notNullValue()));
+		assertThat(person.id).isNotNull();
 
 		person.lastname = null;
 		StepVerifier.create(template.save(person)).expectNextCount(1).verifyComplete();
@@ -889,7 +888,7 @@ public class ReactiveMongoTemplateTests {
 		StepVerifier.create(template.findOne(query(where("id").is(person.id)), VersionedPerson.class)) //
 				.consumeNextWith(actual -> {
 
-					assertThat(actual.lastname, is(nullValue()));
+					assertThat(actual.lastname).isNull();
 				}) //
 				.verifyComplete();
 	}
@@ -906,7 +905,7 @@ public class ReactiveMongoTemplateTests {
 		StepVerifier.create(template.findOne(query(where("id").is(person.getId())), Person.class)) //
 				.consumeNextWith(actual -> {
 
-					assertThat(actual.getFirstName(), is(nullValue()));
+					assertThat(actual.getFirstName()).isNull();
 				}) //
 				.verifyComplete();
 	}
@@ -921,7 +920,7 @@ public class ReactiveMongoTemplateTests {
 		StepVerifier.create(template.findAll(Document.class, "collection")) //
 				.consumeNextWith(actual -> {
 
-					assertThat(actual.containsKey("first"), is(true));
+					assertThat(actual.containsKey("first")).isTrue();
 				}) //
 				.verifyComplete();
 	}
@@ -959,8 +958,8 @@ public class ReactiveMongoTemplateTests {
 
 		Disposable disposable = capped.doOnNext(documents::add).subscribe();
 
-		assertThat(documents.poll(5, TimeUnit.SECONDS), is(notNullValue()));
-		assertThat(documents.isEmpty(), is(true));
+		assertThat(documents.poll(5, TimeUnit.SECONDS)).isNotNull();
+		assertThat(documents).isEmpty();
 
 		disposable.dispose();
 	}
@@ -981,14 +980,14 @@ public class ReactiveMongoTemplateTests {
 
 		Disposable disposable = capped.doOnNext(documents::add).subscribe();
 
-		assertThat(documents.poll(5, TimeUnit.SECONDS), is(notNullValue()));
-		assertThat(documents.isEmpty(), is(true));
+		assertThat(documents.poll(5, TimeUnit.SECONDS)).isNotNull();
+		assertThat(documents).isEmpty();
 
 		StepVerifier.create(template.insert(new Document("random", Math.random()).append("key", "value"), "capped")) //
 				.expectNextCount(1) //
 				.verifyComplete();
 
-		assertThat(documents.poll(5, TimeUnit.SECONDS), is(notNullValue()));
+		assertThat(documents.poll(5, TimeUnit.SECONDS)).isNotNull();
 
 		disposable.dispose();
 
@@ -996,7 +995,7 @@ public class ReactiveMongoTemplateTests {
 				.expectNextCount(1) //
 				.verifyComplete();
 
-		assertThat(documents.poll(1, TimeUnit.SECONDS), is(nullValue()));
+		assertThat(documents.poll(1, TimeUnit.SECONDS)).isNull();
 	}
 
 	@Test // DATAMONGO-1761