Release version 4.3.8 (2021.1.8).

See #2297

Jenkinsfile

@@ -20,8 +20,9 @@ pipeline {
 	stages {
 		stage("test: baseline (main)") {
 			when {
+				beforeAgent(true)
 				anyOf {
-					branch 'main'
+					branch(pattern: "main|(\\d\\.\\d\\.x)", comparator: "REGEXP")
 					not { triggeredBy 'UpstreamCause' }
 				}
 			}
@@ -108,8 +109,9 @@ pipeline {
 
 		stage('Release to artifactory') {
 			when {
+				beforeAgent(true)
 				anyOf {
-					branch 'main'
+					branch(pattern: "main|(\\d\\.\\d\\.x)", comparator: "REGEXP")
 					not { triggeredBy 'UpstreamCause' }
 				}
 			}

pom.xml

@@ -5,12 +5,12 @@
 
 	<groupId>org.springframework.data</groupId>
 	<artifactId>spring-data-elasticsearch</artifactId>
-	<version>4.3.6</version>
+	<version>4.3.8</version>
 
 	<parent>
 		<groupId>org.springframework.data.build</groupId>
 		<artifactId>spring-data-parent</artifactId>
-		<version>2.6.6</version>
+		<version>2.6.8</version>
 	</parent>
 
 	<name>Spring Data Elasticsearch</name>
@@ -21,7 +21,7 @@
 		<elasticsearch>7.15.2</elasticsearch>
 		<log4j>2.17.0</log4j>
 		<netty>4.1.65.Final</netty>
-		<springdata.commons>2.6.6</springdata.commons>
+		<springdata.commons>2.6.8</springdata.commons>
 		<testcontainers>1.15.3</testcontainers>
 		<blockhound-junit>1.0.6.RELEASE</blockhound-junit>
 		<java-module-name>spring.data.elasticsearch</java-module-name>

src/main/java/org/springframework/data/elasticsearch/client/util/RequestConverters.java

@@ -336,8 +336,13 @@ public class RequestConverters {
 	public static Request index(IndexRequest indexRequest) {
 		String method = Strings.hasLength(indexRequest.id()) ? HttpMethod.PUT.name() : HttpMethod.POST.name();
 		boolean isCreate = (indexRequest.opType() == DocWriteRequest.OpType.CREATE);
-		String endpoint = endpoint(indexRequest.index(), indexRequest.type(), indexRequest.id(),
-				isCreate ? "_create" : null);
+		String endpoint;
+		if (indexRequest.opType() == DocWriteRequest.OpType.CREATE) {
+			endpoint = indexRequest.type().equals("_doc") ? endpoint(indexRequest.index(), "_create", indexRequest.id())
+					: endpoint(indexRequest.index(), indexRequest.type(), indexRequest.id(), "_create");
+		} else {
+			endpoint = endpoint(indexRequest.index(), indexRequest.type(), indexRequest.id());
+		}
 		Request request = new Request(method, endpoint);
 
 		Params parameters = new Params(request);
@@ -362,7 +367,9 @@ public class RequestConverters {
 	}
 
 	public static Request update(UpdateRequest updateRequest) {
-		String endpoint = endpoint(updateRequest.index(), updateRequest.type(), updateRequest.id(), "_update");
+		String endpoint = updateRequest.type().equals("_doc")
+				? endpoint(updateRequest.index(), "_update", updateRequest.id())
+				: endpoint(updateRequest.index(), updateRequest.type(), updateRequest.id(), "_update");
 		Request request = new Request(HttpMethod.POST.name(), endpoint);
 
 		Params parameters = new Params(request);
@@ -500,8 +507,11 @@ public class RequestConverters {
 	}
 
 	public static Request explain(ExplainRequest explainRequest) {
+		String endpoint = explainRequest.type().equals("_doc")
+				? endpoint(explainRequest.index(), "_explain", explainRequest.id())
+				: endpoint(explainRequest.index(), explainRequest.type(), explainRequest.id(), "_explain");
 		Request request = new Request(HttpMethod.GET.name(),
-				endpoint(explainRequest.index(), explainRequest.type(), explainRequest.id(), "_explain"));
+				endpoint(explainRequest.index(), explainRequest.type(), explainRequest.id(), endpoint));
 
 		Params params = new Params(request);
 		params.withStoredFields(explainRequest.storedFields());

src/main/java/org/springframework/data/elasticsearch/core/convert/MappingElasticsearchConverter.java

@@ -21,6 +21,14 @@ import java.util.Map.Entry;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.stream.Collectors;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import java.time.temporal.TemporalAccessor;
+import java.util.*;
+import java.util.Map.Entry;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.stream.Collectors;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.BeansException;
@@ -51,16 +59,7 @@ import org.springframework.data.mapping.MappingException;
 import org.springframework.data.mapping.PersistentPropertyAccessor;
 import org.springframework.data.mapping.PreferredConstructor;
 import org.springframework.data.mapping.context.MappingContext;
-import org.springframework.data.mapping.model.ConvertingPropertyAccessor;
-import org.springframework.data.mapping.model.DefaultSpELExpressionEvaluator;
-import org.springframework.data.mapping.model.EntityInstantiator;
-import org.springframework.data.mapping.model.EntityInstantiators;
-import org.springframework.data.mapping.model.ParameterValueProvider;
-import org.springframework.data.mapping.model.PersistentEntityParameterValueProvider;
-import org.springframework.data.mapping.model.PropertyValueProvider;
-import org.springframework.data.mapping.model.SpELContext;
-import org.springframework.data.mapping.model.SpELExpressionEvaluator;
-import org.springframework.data.mapping.model.SpELExpressionParameterValueProvider;
+import org.springframework.data.mapping.model.*;
 import org.springframework.data.util.ClassTypeInformation;
 import org.springframework.data.util.TypeInformation;
 import org.springframework.format.datetime.DateFormatterRegistrar;
@@ -196,7 +195,7 @@ public class MappingElasticsearchConverter
 	}
 
 	/**
-	 * Class to do the actual writing. The methods originally were in the MappingElasticsearchConverter class, but are
+	 * Class to do the actual reading. The methods originally were in the MappingElasticsearchConverter class, but are
 	 * refactored to allow for keeping state during the conversion of an object.
 	 */
 	private static class Reader extends Base {
@@ -215,10 +214,17 @@ public class MappingElasticsearchConverter
 		}
 
 		@SuppressWarnings("unchecked")
+		/**
+		 * Reads the given source into the given type.
+		 *
+		 * @param type they type to convert the given source to.
+		 * @param source the source to create an object of the given type from.
+		 * @return the object that was read
+		 */
 		<R> R read(Class<R> type, Document source) {
 
-			TypeInformation<R> typeHint = ClassTypeInformation.from((Class<R>) ClassUtils.getUserClass(type));
-			R r = read(typeHint, source);
+			TypeInformation<R> typeInformation = ClassTypeInformation.from((Class<R>) ClassUtils.getUserClass(type));
+			R r = read(typeInformation, source);
 
 			if (r == null) {
 				throw new ConversionException("could not convert into object of class " + type);
@@ -229,11 +235,11 @@ public class MappingElasticsearchConverter
 
 		@Nullable
 		@SuppressWarnings("unchecked")
-		private <R> R read(TypeInformation<R> type, Map<String, Object> source) {
+		private <R> R read(TypeInformation<R> typeInformation, Map<String, Object> source) {
 
 			Assert.notNull(source, "Source must not be null!");
 
-			TypeInformation<? extends R> typeToUse = typeMapper.readType(source, type);
+			TypeInformation<? extends R> typeToUse = typeMapper.readType(source, typeInformation);
 			Class<? extends R> rawType = typeToUse.getType();
 
 			if (conversions.hasCustomReadTarget(source.getClass(), rawType)) {
@@ -251,8 +257,8 @@ public class MappingElasticsearchConverter
 			if (typeToUse.equals(ClassTypeInformation.OBJECT)) {
 				return (R) source;
 			}
-			// Retrieve persistent entity info
 
+			// Retrieve persistent entity info
 			ElasticsearchPersistentEntity<?> entity = mappingContext.getPersistentEntity(typeToUse);
 
 			if (entity == null) {
@@ -370,7 +376,6 @@ public class MappingElasticsearchConverter
 			}
 
 			return result;
-
 		}
 
 		private ParameterValueProvider<ElasticsearchPersistentProperty> getParameterProvider(
@@ -460,12 +465,44 @@ public class MappingElasticsearchConverter
 			} else if (value.getClass().isArray()) {
 				return (T) readCollectionOrArray(type, Arrays.asList((Object[]) value));
 			} else if (value instanceof Map) {
+
+				TypeInformation<?> collectionComponentType = getCollectionComponentType(type);
+				if (collectionComponentType != null) {
+					Object o = read(collectionComponentType, (Map<String, Object>) value);
+					return getCollectionWithSingleElement(type, collectionComponentType, o);
+				}
 				return (T) read(type, (Map<String, Object>) value);
 			} else {
+
+				TypeInformation<?> collectionComponentType = getCollectionComponentType(type);
+				if (collectionComponentType != null
+						&& collectionComponentType.isAssignableFrom(ClassTypeInformation.from(value.getClass()))) {
+					Object o = getPotentiallyConvertedSimpleRead(value, collectionComponentType);
+					return getCollectionWithSingleElement(type, collectionComponentType, o);
+				}
+
 				return (T) getPotentiallyConvertedSimpleRead(value, rawType);
 			}
 		}
 
+		@SuppressWarnings("unchecked")
+		private static <T> T getCollectionWithSingleElement(TypeInformation<?> collectionType,
+				TypeInformation<?> componentType, Object element) {
+			Collection<Object> collection = CollectionFactory.createCollection(collectionType.getType(),
+					componentType.getType(), 1);
+			collection.add(element);
+			return (T) collection;
+		}
+
+		/**
+		 * @param type the type to check
+		 * @return true if type is a collectoin, null otherwise,
+		 */
+		@Nullable
+		TypeInformation<?> getCollectionComponentType(TypeInformation<?> type) {
+			return type.isCollectionLike() ? type.getComponentType() : null;
+		}
+
 		private Object propertyConverterRead(ElasticsearchPersistentProperty property, Object source) {
 			PropertyValueConverter propertyValueConverter = Objects.requireNonNull(property.getPropertyValueConverter());
 
@@ -1131,17 +1168,18 @@ public class MappingElasticsearchConverter
 
 		Assert.notNull(query, "query must not be null");
 
-		if (domainClass != null) {
+		if (domainClass == null) {
+			return;
+		}
 
-			updateFieldsAndSourceFilter(query, domainClass);
+		updatePropertiesInFieldsAndSourceFilter(query, domainClass);
 
-			if (query instanceof CriteriaQuery) {
-				updateCriteriaQuery((CriteriaQuery) query, domainClass);
-			}
+		if (query instanceof CriteriaQuery) {
+			updatePropertiesInCriteriaQuery((CriteriaQuery) query, domainClass);
 		}
 	}
 
-	private void updateFieldsAndSourceFilter(Query query, Class<?> domainClass) {
+	private void updatePropertiesInFieldsAndSourceFilter(Query query, Class<?> domainClass) {
 
 		ElasticsearchPersistentEntity<?> persistentEntity = mappingContext.getPersistentEntity(domainClass);
 
@@ -1174,14 +1212,22 @@ public class MappingElasticsearchConverter
 		}
 	}
 
-	private List<String> updateFieldNames(List<String> fields, ElasticsearchPersistentEntity<?> persistentEntity) {
-		return fields.stream().map(fieldName -> {
+	/**
+	 * relaces the fieldName with the property name of a property of the persistentEntity with the corresponding
+	 * fieldname. If no such property exists, the original fieldName is kept.
+	 *
+	 * @param fieldNames list of fieldnames
+	 * @param persistentEntity the persistent entity to check
+	 * @return an updated list of field names
+	 */
+	private List<String> updateFieldNames(List<String> fieldNames, ElasticsearchPersistentEntity<?> persistentEntity) {
+		return fieldNames.stream().map(fieldName -> {
 			ElasticsearchPersistentProperty persistentProperty = persistentEntity.getPersistentProperty(fieldName);
 			return persistentProperty != null ? persistentProperty.getFieldName() : fieldName;
 		}).collect(Collectors.toList());
 	}
 
-	private void updateCriteriaQuery(CriteriaQuery criteriaQuery, Class<?> domainClass) {
+	private void updatePropertiesInCriteriaQuery(CriteriaQuery criteriaQuery, Class<?> domainClass) {
 
 		Assert.notNull(criteriaQuery, "criteriaQuery must not be null");
 		Assert.notNull(domainClass, "domainClass must not be null");
@@ -1190,17 +1236,17 @@ public class MappingElasticsearchConverter
 
 		if (persistentEntity != null) {
 			for (Criteria chainedCriteria : criteriaQuery.getCriteria().getCriteriaChain()) {
-				updateCriteria(chainedCriteria, persistentEntity);
+				updatePropertiesInCriteria(chainedCriteria, persistentEntity);
 			}
 			for (Criteria subCriteria : criteriaQuery.getCriteria().getSubCriteria()) {
 				for (Criteria chainedCriteria : subCriteria.getCriteriaChain()) {
-					updateCriteria(chainedCriteria, persistentEntity);
+					updatePropertiesInCriteria(chainedCriteria, persistentEntity);
 				}
 			}
 		}
 	}
 
-	private void updateCriteria(Criteria criteria, ElasticsearchPersistentEntity<?> persistentEntity) {
+	private void updatePropertiesInCriteria(Criteria criteria, ElasticsearchPersistentEntity<?> persistentEntity) {
 
 		Field field = criteria.getField();
 

src/main/java/org/springframework/data/elasticsearch/repository/query/ElasticsearchPartQuery.java

@@ -128,6 +128,9 @@ public class ElasticsearchPartQuery extends AbstractElasticsearchRepositoryQuery
 
 		} else if (tree.isCountProjection()) {
 			result = elasticsearchOperations.count(query, clazz, index);
+		} else if (tree.isExistsProjection()) {
+			long count = elasticsearchOperations.count(query, clazz, index);
+			result = count > 0;
 		} else {
 			result = elasticsearchOperations.searchOne(query, clazz, index);
 		}

src/main/java/org/springframework/data/elasticsearch/repository/support/StringQueryUtil.java

@@ -46,7 +46,11 @@ final public class StringQueryUtil {
 
 			String placeholder = Pattern.quote(matcher.group()) + "(?!\\d+)";
 			int index = NumberUtils.parseNumber(matcher.group(1), Integer.class);
-			result = result.replaceAll(placeholder, Matcher.quoteReplacement(getParameterWithIndex(accessor, index)));
+			String replacement = Matcher.quoteReplacement(getParameterWithIndex(accessor, index));
+			result = result.replaceAll(placeholder, replacement);
+			// need to escape backslashes that are not escapes for quotes so that they are sent as double-backslashes
+			// to Elasticsearch
+			result = result.replaceAll("\\\\([^\"'])", "\\\\\\\\$1");
 		}
 		return result;
 	}
@@ -56,7 +60,6 @@ final public class StringQueryUtil {
 		Object parameter = accessor.getBindableValue(index);
 		String parameterValue = "null";
 
-		// noinspection ConstantConditions
 		if (parameter != null) {
 
 			parameterValue = convert(parameter);

src/main/resources/notice.txt

@@ -1,4 +1,4 @@
-Spring Data Elasticsearch 4.3.6 (2021.1.6)
+Spring Data Elasticsearch 4.3.8 (2021.1.8)
 Copyright (c) [2013-2021] Pivotal Software, Inc.
 
 This product is licensed to you under the Apache License, Version 2.0 (the "License").
@@ -35,6 +35,8 @@ conditions of the subcomponent's license, as noted in the LICENSE file.
 
 
 
+
+
 
 
 

src/test/java/org/springframework/data/elasticsearch/client/reactive/ReactiveElasticsearchClientUnitTests.java

@@ -375,7 +375,7 @@ public class ReactiveElasticsearchClientUnitTests {
 		});
 
 		URI uri = hostProvider.when(HOST).captureUri();
-		assertThat(uri.getRawPath()).isEqualTo("/twitter/_doc/10/_create");
+		assertThat(uri.getRawPath()).isEqualTo("/twitter/_create/10");
 	}
 
 	@Test // DATAES-488
@@ -439,7 +439,7 @@ public class ReactiveElasticsearchClientUnitTests {
 		hostProvider.when(HOST) //
 				.receiveUpdateOk();
 
-		client.update(new UpdateRequest("twitter", "doc", "1").doc(Collections.singletonMap("user", "cstrobl"))).then() //
+		client.update(new UpdateRequest("twitter", "1").doc(Collections.singletonMap("user", "cstrobl"))).then() //
 				.as(StepVerifier::create) //
 				.verifyComplete();
 
@@ -449,7 +449,7 @@ public class ReactiveElasticsearchClientUnitTests {
 		});
 
 		URI uri = hostProvider.when(HOST).captureUri();
-		assertThat(uri.getRawPath()).isEqualTo("/twitter/doc/1/_update");
+		assertThat(uri.getRawPath()).isEqualTo("/twitter/_update/1");
 	}
 
 	@Test // DATAES-488

src/test/java/org/springframework/data/elasticsearch/core/convert/MappingElasticsearchConverterUnitTests.java

@@ -33,6 +33,8 @@ import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
+import java.util.stream.Collectors;
 
 import org.json.JSONException;
 import org.junit.jupiter.api.BeforeEach;
@@ -623,7 +625,8 @@ public class MappingElasticsearchConverterUnitTests {
 		assertThat(target.address).isEqualTo(bigBunsCafe);
 	}
 
-	@Test // DATAES-716
+	@Test
+	// DATAES-716
 	void shouldWriteLocalDate() throws JSONException {
 		Person person = new Person();
 		person.setId("4711");
@@ -665,7 +668,8 @@ public class MappingElasticsearchConverterUnitTests {
 		assertEquals(expected, json, false);
 	}
 
-	@Test // DATAES-716
+	@Test
+	// DATAES-716
 	void shouldReadLocalDate() {
 		Document document = Document.create();
 		document.put("id", "4711");
@@ -695,7 +699,8 @@ public class MappingElasticsearchConverterUnitTests {
 		assertThat(entity.getDates()).hasSize(2).containsExactly(LocalDate.of(2020, 9, 15), LocalDate.of(2019, 5, 1));
 	}
 
-	@Test // DATAES-763
+	@Test
+	// DATAES-763
 	void writeEntityWithMapDataType() {
 
 		Notification notification = new Notification();
@@ -712,7 +717,8 @@ public class MappingElasticsearchConverterUnitTests {
 		assertThat(document).isEqualTo(notificationAsMap);
 	}
 
-	@Test // DATAES-763
+	@Test
+	// DATAES-763
 	void readEntityWithMapDataType() {
 
 		Document document = Document.create();
@@ -729,7 +735,8 @@ public class MappingElasticsearchConverterUnitTests {
 		assertThat(notification.params.get("content")).isNull();
 	}
 
-	@Test // DATAES-795
+	@Test
+	// DATAES-795
 	void readGenericMapWithSimpleTypes() {
 		Map<String, Object> mapWithSimpleValues = new HashMap<>();
 		mapWithSimpleValues.put("int", 1);
@@ -743,7 +750,8 @@ public class MappingElasticsearchConverterUnitTests {
 		assertThat(wrapper.getSchemaLessObject()).isEqualTo(mapWithSimpleValues);
 	}
 
-	@Test // DATAES-797
+	@Test
+	// DATAES-797
 	void readGenericListWithMaps() {
 		Map<String, Object> simpleMap = new HashMap<>();
 		simpleMap.put("int", 1);
@@ -761,7 +769,8 @@ public class MappingElasticsearchConverterUnitTests {
 		assertThat(wrapper.getSchemaLessObject()).isEqualTo(mapWithSimpleList);
 	}
 
-	@Test // DATAES-799
+	@Test
+	// DATAES-799
 	void shouldNotWriteSeqNoPrimaryTermProperty() {
 		EntityWithSeqNoPrimaryTerm entity = new EntityWithSeqNoPrimaryTerm();
 		entity.seqNoPrimaryTerm = new SeqNoPrimaryTerm(1L, 2L);
@@ -772,7 +781,8 @@ public class MappingElasticsearchConverterUnitTests {
 		assertThat(document).doesNotContainKey("seqNoPrimaryTerm");
 	}
 
-	@Test // DATAES-799
+	@Test
+	// DATAES-799
 	void shouldNotReadSeqNoPrimaryTermProperty() {
 		Document document = Document.create().append("seqNoPrimaryTerm", emptyMap());
 
@@ -781,7 +791,8 @@ public class MappingElasticsearchConverterUnitTests {
 		assertThat(entity.seqNoPrimaryTerm).isNull();
 	}
 
-	@Test // DATAES-845
+	@Test
+	// DATAES-845
 	void shouldWriteCollectionsWithNullValues() throws JSONException {
 		EntityWithListProperty entity = new EntityWithListProperty();
 		entity.setId("42");
@@ -798,7 +809,8 @@ public class MappingElasticsearchConverterUnitTests {
 		assertEquals(expected, json, false);
 	}
 
-	@Test // DATAES-857
+	@Test
+	// DATAES-857
 	void shouldWriteEntityWithListOfGeoPoints() throws JSONException {
 
 		GeoPointListEntity entity = new GeoPointListEntity();
@@ -827,7 +839,8 @@ public class MappingElasticsearchConverterUnitTests {
 		assertEquals(expected, json, false);
 	}
 
-	@Test // DATAES-857
+	@Test
+	// DATAES-857
 	void shouldReadEntityWithListOfGeoPoints() {
 
 		String json = "{\n" + //
@@ -852,7 +865,8 @@ public class MappingElasticsearchConverterUnitTests {
 		assertThat(entity.locations).containsExactly(new GeoPoint(12.34, 23.45), new GeoPoint(34.56, 45.67));
 	}
 
-	@Test // DATAES-865
+	@Test
+	// DATAES-865
 	void shouldWriteEntityWithMapAsObject() throws JSONException {
 
 		Map<String, Object> map = new LinkedHashMap<>();
@@ -1509,6 +1523,305 @@ public class MappingElasticsearchConverterUnitTests {
 		mappingElasticsearchConverter.updateQuery(query, EntityWithCustomValueConverters.class);
 	}
 
+	@Test // #2280
+	@DisplayName("should read a single String into a List property")
+	void shouldReadASingleStringIntoAListProperty() {
+
+		String json = "{\n" + //
+				"  \"stringList\": \"foo\"\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		EntityWithCollections entity = mappingElasticsearchConverter.read(EntityWithCollections.class, source);
+
+		assertThat(entity.getStringList()).containsExactly("foo");
+	}
+
+	@Test // #2280
+	@DisplayName("should read a String array into a List property")
+	void shouldReadAStringArrayIntoAListProperty() {
+
+		String json = "{\n" + //
+				"  \"stringList\": [\"foo\", \"bar\"]\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		EntityWithCollections entity = mappingElasticsearchConverter.read(EntityWithCollections.class, source);
+
+		assertThat(entity.getStringList()).containsExactly("foo", "bar");
+	}
+
+	@Test // #2280
+	@DisplayName("should read a single String into a Set property")
+	void shouldReadASingleStringIntoASetProperty() {
+
+		String json = "{\n" + //
+				"  \"stringSet\": \"foo\"\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		EntityWithCollections entity = mappingElasticsearchConverter.read(EntityWithCollections.class, source);
+
+		assertThat(entity.getStringSet()).containsExactly("foo");
+	}
+
+	@Test // #2280
+	@DisplayName("should read a String array into a Set property")
+	void shouldReadAStringArrayIntoASetProperty() {
+
+		String json = "{\n" + //
+				"  \"stringSet\": [\n" + //
+				"    \"foo\",\n" + //
+				"    \"bar\"\n" + //
+				"  ]\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		EntityWithCollections entity = mappingElasticsearchConverter.read(EntityWithCollections.class, source);
+
+		assertThat(entity.getStringSet()).containsExactly("foo", "bar");
+	}
+
+	@Test // #2280
+	@DisplayName("should read a single object into a List property")
+	void shouldReadASingleObjectIntoAListProperty() {
+
+		String json = "{\n" + //
+				"  \"childrenList\": {\n" + //
+				"    \"name\": \"child\"\n" + //
+				"  }\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		EntityWithCollections entity = mappingElasticsearchConverter.read(EntityWithCollections.class, source);
+
+		assertThat(entity.getChildrenList()).hasSize(1);
+		// noinspection ConstantConditions
+		assertThat(entity.getChildrenList().get(0).getName()).isEqualTo("child");
+	}
+
+	@Test // #2280
+	@DisplayName("should read an object array into a List property")
+	void shouldReadAnObjectArrayIntoAListProperty() {
+
+		String json = "        {\n" + //
+				"          \"childrenList\": [\n" + //
+				"            {\n" + //
+				"              \"name\": \"child1\"\n" + //
+				"            },\n" + //
+				"            {\n" + //
+				"              \"name\": \"child2\"\n" + //
+				"            }\n" + //
+				"          ]\n" + //
+				"        }\n"; //
+		Document source = Document.parse(json);
+
+		EntityWithCollections entity = mappingElasticsearchConverter.read(EntityWithCollections.class, source);
+
+		assertThat(entity.getChildrenList()).hasSize(2);
+		// noinspection ConstantConditions
+		assertThat(entity.getChildrenList().get(0).getName()).isEqualTo("child1");
+		assertThat(entity.getChildrenList().get(1).getName()).isEqualTo("child2");
+	}
+
+	@Test // #2280
+	@DisplayName("should read a single object into a Set property")
+	void shouldReadASingleObjectIntoASetProperty() {
+
+		String json = "{\n" + //
+				"  \"childrenSet\": {\n" + //
+				"    \"name\": \"child\"\n" + //
+				"  }\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		EntityWithCollections entity = mappingElasticsearchConverter.read(EntityWithCollections.class, source);
+
+		assertThat(entity.getChildrenSet()).hasSize(1);
+		// noinspection ConstantConditions
+		assertThat(entity.getChildrenSet().iterator().next().getName()).isEqualTo("child");
+	}
+
+	@Test // #2280
+	@DisplayName("should read an object array into a Set property")
+	void shouldReadAnObjectArrayIntoASetProperty() {
+
+		String json = "{\n" + //
+				"  \"childrenSet\": [\n" + //
+				"    {\n" + //
+				"      \"name\": \"child1\"\n" + //
+				"    },\n" + //
+				"    {\n" + //
+				"      \"name\": \"child2\"\n" + //
+				"    }\n" + //
+				"  ]\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		EntityWithCollections entity = mappingElasticsearchConverter.read(EntityWithCollections.class, source);
+
+		assertThat(entity.getChildrenSet()).hasSize(2);
+		// noinspection ConstantConditions
+		List<String> names = entity.getChildrenSet().stream().map(EntityWithCollections.Child::getName)
+				.collect(Collectors.toList());
+		assertThat(names).containsExactlyInAnyOrder("child1", "child2");
+	}
+
+	@Test // #2280
+	@DisplayName("should read a single String into a List property immutable")
+	void shouldReadASingleStringIntoAListPropertyImmutable() {
+
+		String json = "{\n" + //
+				"  \"stringList\": \"foo\"\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		ImmutableEntityWithCollections entity = mappingElasticsearchConverter.read(ImmutableEntityWithCollections.class,
+				source);
+
+		assertThat(entity.getStringList()).containsExactly("foo");
+	}
+
+	@Test // #2280
+	@DisplayName("should read a String array into a List property immutable")
+	void shouldReadAStringArrayIntoAListPropertyImmutable() {
+
+		String json = "{\n" + //
+				"  \"stringList\": [\n" + //
+				"    \"foo\",\n" + //
+				"    \"bar\"\n" + //
+				"  ]\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		ImmutableEntityWithCollections entity = mappingElasticsearchConverter.read(ImmutableEntityWithCollections.class,
+				source);
+
+		assertThat(entity.getStringList()).containsExactly("foo", "bar");
+	}
+
+	@Test // #2280
+	@DisplayName("should read a single String into a Set property immutable")
+	void shouldReadASingleStringIntoASetPropertyImmutable() {
+
+		String json = "{\n" + //
+				"  \"stringSet\": \"foo\"\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		ImmutableEntityWithCollections entity = mappingElasticsearchConverter.read(ImmutableEntityWithCollections.class,
+				source);
+
+		assertThat(entity.getStringSet()).containsExactly("foo");
+	}
+
+	@Test // #2280
+	@DisplayName("should read a String array into a Set property immutable")
+	void shouldReadAStringArrayIntoASetPropertyImmutable() {
+
+		String json = "{\n" + //
+				"  \"stringSet\": [\n" + //
+				"    \"foo\",\n" + //
+				"    \"bar\"\n" + //
+				"  ]\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		ImmutableEntityWithCollections entity = mappingElasticsearchConverter.read(ImmutableEntityWithCollections.class,
+				source);
+
+		assertThat(entity.getStringSet()).containsExactly("foo", "bar");
+	}
+
+	@Test // #2280
+	@DisplayName("should read a single object into a List property immutable")
+	void shouldReadASingleObjectIntoAListPropertyImmutable() {
+
+		String json = "{\n" + //
+				"  \"childrenList\": {\n" + //
+				"    \"name\": \"child\"\n" + //
+				"  }\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		ImmutableEntityWithCollections entity = mappingElasticsearchConverter.read(ImmutableEntityWithCollections.class,
+				source);
+
+		assertThat(entity.getChildrenList()).hasSize(1);
+		// noinspection ConstantConditions
+		assertThat(entity.getChildrenList().get(0).getName()).isEqualTo("child");
+	}
+
+	@Test // #2280
+	@DisplayName("should read an object array into a List property immutable")
+	void shouldReadAnObjectArrayIntoAListPropertyImmutable() {
+
+		String json = "{\n" + //
+				"  \"childrenList\": [\n" + //
+				"    {\n" + //
+				"      \"name\": \"child1\"\n" + //
+				"    },\n" + //
+				"    {\n" + //
+				"      \"name\": \"child2\"\n" + //
+				"    }\n" + //
+				"  ]\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		ImmutableEntityWithCollections entity = mappingElasticsearchConverter.read(ImmutableEntityWithCollections.class,
+				source);
+
+		assertThat(entity.getChildrenList()).hasSize(2);
+		// noinspection ConstantConditions
+		assertThat(entity.getChildrenList().get(0).getName()).isEqualTo("child1");
+		assertThat(entity.getChildrenList().get(1).getName()).isEqualTo("child2");
+	}
+
+	@Test // #2280
+	@DisplayName("should read a single object into a Set property immutable")
+	void shouldReadASingleObjectIntoASetPropertyImmutable() {
+
+		String json = "{\n" + //
+				"  \"childrenSet\": {\n" + //
+				"    \"name\": \"child\"\n" + //
+				"  }\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		ImmutableEntityWithCollections entity = mappingElasticsearchConverter.read(ImmutableEntityWithCollections.class,
+				source);
+
+		assertThat(entity.getChildrenSet()).hasSize(1);
+		// noinspection ConstantConditions
+		assertThat(entity.getChildrenSet().iterator().next().getName()).isEqualTo("child");
+	}
+
+	@Test // #2280
+	@DisplayName("should read an object array into a Set property immutable")
+	void shouldReadAnObjectArrayIntoASetPropertyImmutable() {
+
+		String json = "{\n" + //
+				"  \"childrenSet\": [\n" + //
+				"    {\n" + //
+				"      \"name\": \"child1\"\n" + //
+				"    },\n" + //
+				"    {\n" + //
+				"      \"name\": \"child2\"\n" + //
+				"    }\n" + //
+				"  ]\n" + //
+				"}\n"; //
+		Document source = Document.parse(json);
+
+		ImmutableEntityWithCollections entity = mappingElasticsearchConverter.read(ImmutableEntityWithCollections.class,
+				source);
+
+		assertThat(entity.getChildrenSet()).hasSize(2);
+		// noinspection ConstantConditions
+		List<String> names = entity.getChildrenSet().stream().map(ImmutableEntityWithCollections.Child::getName)
+				.collect(Collectors.toList());
+		assertThat(names).containsExactlyInAnyOrder("child1", "child2");
+	}
+
 	private Map<String, Object> writeToMap(Object source) {
 
 		Document sink = Document.create();
@@ -1561,12 +1874,15 @@ public class MappingElasticsearchConverterUnitTests {
 	}
 
 	static class Person {
-		@Nullable @Id String id;
+		@Nullable
+		@Id String id;
 		@Nullable String name;
-		@Nullable @Field(name = "first-name") String firstName;
-		@Nullable @Field(name = "last-name") String lastName;
-		@Nullable @Field(name = "birth-date", type = FieldType.Date, format = {},
-				pattern = "dd.MM.uuuu") LocalDate birthDate;
+		@Nullable
+		@Field(name = "first-name") String firstName;
+		@Nullable
+		@Field(name = "last-name") String lastName;
+		@Nullable
+		@Field(name = "birth-date", type = FieldType.Date, format = {}, pattern = "dd.MM.uuuu") LocalDate birthDate;
 		@Nullable Gender gender;
 		@Nullable Address address;
 		@Nullable List<Person> coWorkers;
@@ -1675,34 +1991,46 @@ public class MappingElasticsearchConverterUnitTests {
 
 		@Override
 		public boolean equals(Object o) {
-			if (this == o)
+			if (this == o) {
 				return true;
-			if (o == null || getClass() != o.getClass())
+			}
+			if (o == null || getClass() != o.getClass()) {
 				return false;
+			}
 
 			Person person = (Person) o;
 
-			if (id != null ? !id.equals(person.id) : person.id != null)
+			if (id != null ? !id.equals(person.id) : person.id != null) {
 				return false;
-			if (name != null ? !name.equals(person.name) : person.name != null)
+			}
+			if (name != null ? !name.equals(person.name) : person.name != null) {
 				return false;
-			if (firstName != null ? !firstName.equals(person.firstName) : person.firstName != null)
+			}
+			if (firstName != null ? !firstName.equals(person.firstName) : person.firstName != null) {
 				return false;
-			if (lastName != null ? !lastName.equals(person.lastName) : person.lastName != null)
+			}
+			if (lastName != null ? !lastName.equals(person.lastName) : person.lastName != null) {
 				return false;
-			if (birthDate != null ? !birthDate.equals(person.birthDate) : person.birthDate != null)
+			}
+			if (birthDate != null ? !birthDate.equals(person.birthDate) : person.birthDate != null) {
 				return false;
-			if (gender != person.gender)
+			}
+			if (gender != person.gender) {
 				return false;
-			if (address != null ? !address.equals(person.address) : person.address != null)
+			}
+			if (address != null ? !address.equals(person.address) : person.address != null) {
 				return false;
-			if (coWorkers != null ? !coWorkers.equals(person.coWorkers) : person.coWorkers != null)
+			}
+			if (coWorkers != null ? !coWorkers.equals(person.coWorkers) : person.coWorkers != null) {
 				return false;
-			if (inventoryList != null ? !inventoryList.equals(person.inventoryList) : person.inventoryList != null)
+			}
+			if (inventoryList != null ? !inventoryList.equals(person.inventoryList) : person.inventoryList != null) {
 				return false;
+			}
 			if (shippingAddresses != null ? !shippingAddresses.equals(person.shippingAddresses)
-					: person.shippingAddresses != null)
+					: person.shippingAddresses != null) {
 				return false;
+			}
 			return inventoryMap != null ? inventoryMap.equals(person.inventoryMap) : person.inventoryMap == null;
 		}
 
@@ -1724,8 +2052,10 @@ public class MappingElasticsearchConverterUnitTests {
 	}
 
 	static class LocalDatesEntity {
-		@Nullable @Id private String id;
-		@Nullable @Field(name = "dates", type = FieldType.Date, format = DateFormat.custom,
+		@Nullable
+		@Id private String id;
+		@Nullable
+		@Field(name = "dates", type = FieldType.Date, format = DateFormat.custom,
 				pattern = "dd.MM.uuuu") private List<LocalDate> dates;
 
 		@Nullable
@@ -1787,15 +2117,18 @@ public class MappingElasticsearchConverterUnitTests {
 
 		@Override
 		public boolean equals(Object o) {
-			if (this == o)
+			if (this == o) {
 				return true;
-			if (o == null || getClass() != o.getClass())
+			}
+			if (o == null || getClass() != o.getClass()) {
 				return false;
+			}
 
 			Gun gun = (Gun) o;
 
-			if (shotsPerMagazine != gun.shotsPerMagazine)
+			if (shotsPerMagazine != gun.shotsPerMagazine) {
 				return false;
+			}
 			return label.equals(gun.label);
 		}
 
@@ -1821,10 +2154,12 @@ public class MappingElasticsearchConverterUnitTests {
 
 		@Override
 		public boolean equals(Object o) {
-			if (this == o)
+			if (this == o) {
 				return true;
-			if (!(o instanceof Grenade))
+			}
+			if (!(o instanceof Grenade)) {
 				return false;
+			}
 
 			Grenade grenade = (Grenade) o;
 
@@ -1857,17 +2192,21 @@ public class MappingElasticsearchConverterUnitTests {
 
 		@Override
 		public boolean equals(Object o) {
-			if (this == o)
+			if (this == o) {
 				return true;
-			if (!(o instanceof Rifle))
+			}
+			if (!(o instanceof Rifle)) {
 				return false;
+			}
 
 			Rifle rifle = (Rifle) o;
 
-			if (Double.compare(rifle.weight, weight) != 0)
+			if (Double.compare(rifle.weight, weight) != 0) {
 				return false;
-			if (maxShotsPerMagazine != rifle.maxShotsPerMagazine)
+			}
+			if (maxShotsPerMagazine != rifle.maxShotsPerMagazine) {
 				return false;
+			}
 			return label.equals(rifle.label);
 		}
 
@@ -1898,10 +2237,12 @@ public class MappingElasticsearchConverterUnitTests {
 
 		@Override
 		public boolean equals(Object o) {
-			if (this == o)
+			if (this == o) {
 				return true;
-			if (!(o instanceof ShotGun))
+			}
+			if (!(o instanceof ShotGun)) {
 				return false;
+			}
 
 			ShotGun shotGun = (ShotGun) o;
 
@@ -1948,17 +2289,21 @@ public class MappingElasticsearchConverterUnitTests {
 
 		@Override
 		public boolean equals(Object o) {
-			if (this == o)
+			if (this == o) {
 				return true;
-			if (!(o instanceof Address))
+			}
+			if (!(o instanceof Address)) {
 				return false;
+			}
 
 			Address address = (Address) o;
 
-			if (location != null ? !location.equals(address.location) : address.location != null)
+			if (location != null ? !location.equals(address.location) : address.location != null) {
 				return false;
-			if (street != null ? !street.equals(address.street) : address.street != null)
+			}
+			if (street != null ? !street.equals(address.street) : address.street != null) {
 				return false;
+			}
 			return city != null ? city.equals(address.city) : address.city == null;
 		}
 
@@ -1985,10 +2330,12 @@ public class MappingElasticsearchConverterUnitTests {
 
 		@Override
 		public boolean equals(Object o) {
-			if (this == o)
+			if (this == o) {
 				return true;
-			if (!(o instanceof Place))
+			}
+			if (!(o instanceof Place)) {
 				return false;
+			}
 
 			Place place = (Place) o;
 
@@ -2124,16 +2471,20 @@ public class MappingElasticsearchConverterUnitTests {
 
 	@org.springframework.data.elasticsearch.annotations.Document(indexName = "test-index-geo-core-entity-mapper")
 	static class GeoEntity {
-		@Nullable @Id private String id;
+		@Nullable
+		@Id private String id;
 		// geo shape - Spring Data
 		@Nullable private Box box;
 		@Nullable private Circle circle;
 		@Nullable private Polygon polygon;
 		// geo point - Custom implementation + Spring Data
-		@Nullable @GeoPointField private Point pointA;
+		@Nullable
+		@GeoPointField private Point pointA;
 		@Nullable private GeoPoint pointB;
-		@Nullable @GeoPointField private String pointC;
-		@Nullable @GeoPointField private double[] pointD;
+		@Nullable
+		@GeoPointField private String pointC;
+		@Nullable
+		@GeoPointField private double[] pointD;
 
 		@Nullable
 		public String getId() {
@@ -2237,7 +2588,8 @@ public class MappingElasticsearchConverterUnitTests {
 	}
 
 	static class EntityWithListProperty {
-		@Nullable @Id private String id;
+		@Nullable
+		@Id private String id;
 		@Nullable private List<String> values;
 
 		@Nullable
@@ -2283,7 +2635,8 @@ public class MappingElasticsearchConverterUnitTests {
 	}
 
 	static class EntityWithObject {
-		@Nullable @Id private String id;
+		@Nullable
+		@Id private String id;
 		@Nullable private Object content;
 
 		@Nullable
@@ -2306,9 +2659,12 @@ public class MappingElasticsearchConverterUnitTests {
 	}
 
 	static class EntityWithNullField {
-		@Nullable @Id private String id;
-		@Nullable @Field(type = FieldType.Text) private String notSaved;
-		@Nullable @Field(type = FieldType.Text, storeNullValue = true) private String saved;
+		@Nullable
+		@Id private String id;
+		@Nullable
+		@Field(type = FieldType.Text) private String notSaved;
+		@Nullable
+		@Field(type = FieldType.Text, storeNullValue = true) private String saved;
 
 		@Nullable
 		public String getId() {
@@ -2341,9 +2697,12 @@ public class MappingElasticsearchConverterUnitTests {
 	private static class ElectricCar extends Car {}
 
 	private static class PersonWithCars {
-		@Id @Nullable String id;
-		@Field(type = FieldType.Text) @Nullable private String name;
-		@Field(type = FieldType.Nested) @Nullable private List<? extends Car> cars;
+		@Id
+		@Nullable String id;
+		@Field(type = FieldType.Text)
+		@Nullable private String name;
+		@Field(type = FieldType.Nested)
+		@Nullable private List<? extends Car> cars;
 
 		@Nullable
 		public String getId() {
@@ -2374,9 +2733,12 @@ public class MappingElasticsearchConverterUnitTests {
 	}
 
 	private static class EntityWithCustomValueConverters {
-		@Nullable @Id private String id;
-		@Nullable @ValueConverter(ClassBasedValueConverter.class) private String fieldWithClassBasedConverter;
-		@Nullable @ValueConverter(EnumBasedValueConverter.class) private String fieldWithEnumBasedConverter;
+		@Nullable
+		@Id private String id;
+		@Nullable
+		@ValueConverter(ClassBasedValueConverter.class) private String fieldWithClassBasedConverter;
+		@Nullable
+		@ValueConverter(EnumBasedValueConverter.class) private String fieldWithEnumBasedConverter;
 		@Nullable private String dontConvert;
 
 		@Nullable
@@ -2442,6 +2804,128 @@ public class MappingElasticsearchConverterUnitTests {
 			return reverse(value);
 		}
 	}
+
+	private static class EntityWithCollections {
+		@Field(type = FieldType.Keyword)
+		@Nullable private List<String> stringList;
+
+		@Field(type = FieldType.Keyword)
+		@Nullable private Set<String> stringSet;
+
+		@Field(type = FieldType.Object)
+		@Nullable private List<Child> childrenList;
+
+		@Field(type = FieldType.Object)
+		@Nullable private Set<Child> childrenSet;
+
+		@Nullable
+		public List<String> getStringList() {
+			return stringList;
+		}
+
+		public void setStringList(@Nullable List<String> stringList) {
+			this.stringList = stringList;
+		}
+
+		@Nullable
+		public Set<String> getStringSet() {
+			return stringSet;
+		}
+
+		public void setStringSet(@Nullable Set<String> stringSet) {
+			this.stringSet = stringSet;
+		}
+
+		@Nullable
+		public List<Child> getChildrenList() {
+			return childrenList;
+		}
+
+		public void setChildrenList(@Nullable List<Child> childrenList) {
+			this.childrenList = childrenList;
+		}
+
+		@Nullable
+		public Set<Child> getChildrenSet() {
+			return childrenSet;
+		}
+
+		public void setChildrenSet(@Nullable Set<Child> childrenSet) {
+			this.childrenSet = childrenSet;
+		}
+
+		public static class Child {
+
+			@Field(type = FieldType.Keyword)
+			@Nullable private String name;
+
+			@Nullable
+			public String getName() {
+				return name;
+			}
+
+			public void setName(String name) {
+				this.name = name;
+			}
+		}
+	}
+
+	private static final class ImmutableEntityWithCollections {
+		@Field(type = FieldType.Keyword)
+		@Nullable private List<String> stringList;
+
+		@Field(type = FieldType.Keyword)
+		@Nullable private Set<String> stringSet;
+
+		@Field(type = FieldType.Object)
+		@Nullable private List<Child> childrenList;
+
+		@Field(type = FieldType.Object)
+		@Nullable private Set<Child> childrenSet;
+
+		public ImmutableEntityWithCollections(@Nullable List<String> stringList, @Nullable Set<String> stringSet,
+				@Nullable List<Child> childrenList, @Nullable Set<Child> childrenSet) {
+			this.stringList = stringList;
+			this.stringSet = stringSet;
+			this.childrenList = childrenList;
+			this.childrenSet = childrenSet;
+		}
+
+		@Nullable
+		public List<String> getStringList() {
+			return stringList;
+		}
+
+		@Nullable
+		public Set<String> getStringSet() {
+			return stringSet;
+		}
+
+		@Nullable
+		public List<Child> getChildrenList() {
+			return childrenList;
+		}
+
+		@Nullable
+		public Set<Child> getChildrenSet() {
+			return childrenSet;
+		}
+
+		public static class Child {
+
+			@Field(type = FieldType.Keyword)
+			@Nullable private String name;
+
+			public Child(@Nullable String name) {
+				this.name = name;
+			}
+
+			@Nullable
+			public String getName() {
+				return name;
+			}
+		}
+	}
 	// endregion
 
 	private static String reverse(Object o) {

src/test/java/org/springframework/data/elasticsearch/repository/query/ElasticsearchStringQueryUnitTests.java

@@ -129,6 +129,18 @@ public class ElasticsearchStringQueryUnitTests extends ElasticsearchStringQueryU
 				"{ 'bool' : { 'must' : { 'terms' : { 'name' : [\"hello \\\"Stranger\\\"\",\"Another string\"] } } } }");
 	}
 
+	@Test // #2326
+	@DisplayName("should escape backslashes in collection query parameters")
+	void shouldEscapeBackslashesInCollectionQueryParameters() throws NoSuchMethodException {
+
+		final List<String> parameters = Arrays.asList("param\\1", "param\\2");
+		List<String> params = new ArrayList<>(parameters);
+		org.springframework.data.elasticsearch.core.query.Query query = createQuery("findByNameIn", params);
+
+		assertThat(query).isInstanceOf(StringQuery.class);
+		assertThat(((StringQuery) query).getSource()).isEqualTo(
+			"{ 'bool' : { 'must' : { 'terms' : { 'name' : [\"param\\\\1\",\"param\\\\2\"] } } } }");
+	}
 	private org.springframework.data.elasticsearch.core.query.Query createQuery(String methodName, Object... args)
 			throws NoSuchMethodException {
 

src/test/java/org/springframework/data/elasticsearch/repository/query/keywords/QueryKeywordsTests.java

@@ -321,6 +321,17 @@ class QueryKeywordsTests {
 		assertThat(searchHits.getTotalHits()).isEqualTo(5);
 	}
 
+	@Test // #2162
+	@DisplayName("should run exists query")
+	void shouldRunExistsQuery() {
+
+		Boolean existsCaneSugar = repository.existsByText("Cane sugar");
+		Boolean existsSand = repository.existsByText("Sand");
+
+		assertThat(existsCaneSugar).isTrue();
+		assertThat(existsSand).isFalse();
+	}
+
 	@SuppressWarnings("unused")
 	@Document(indexName = "test-index-product-query-keywords")
 	static class Product {
@@ -459,6 +470,8 @@ class QueryKeywordsTests {
 		SearchHits<Product> findByNameEmpty();
 
 		SearchHits<Product> findByNameNotEmpty();
+
+		Boolean existsByText(String text);
 	}
 
 }

src/test/java/org/springframework/data/elasticsearch/repository/query/keywords/ReactiveQueryKeywordsIntegrationTests.java

@@ -19,8 +19,11 @@ import static org.assertj.core.api.Assertions.*;
 import static org.springframework.data.elasticsearch.annotations.FieldType.*;
 
 import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
 import reactor.test.StepVerifier;
 
+import java.lang.Boolean;
+
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Order;
@@ -139,6 +142,21 @@ public class ReactiveQueryKeywordsIntegrationTests {
 				}).verifyComplete();
 	}
 
+	@Test // #2162
+	@DisplayName("should run exists query")
+	void shouldRunExistsQuery() {
+
+		loadEntities();
+		repository.existsByMessage("message") //
+				.as(StepVerifier::create) //
+				.expectNext(true) //
+				.verifyComplete();
+		repository.existsByMessage("without") //
+				.as(StepVerifier::create) //
+				.expectNext(false) //
+				.verifyComplete();
+	}
+
 	@SuppressWarnings("SpringDataMethodInconsistencyInspection")
 	interface SampleRepository extends ReactiveElasticsearchRepository<SampleEntity, String> {
 		Flux<SearchHit<SampleEntity>> findByMessageExists();
@@ -150,6 +168,8 @@ public class ReactiveQueryKeywordsIntegrationTests {
 		Flux<SearchHit<SampleEntity>> findByMessageIsNotEmpty();
 
 		Flux<SearchHit<SampleEntity>> findByMessageIsEmpty();
+
+		Mono<Boolean> existsByMessage(String message);
 	}
 
 	private void loadEntities() {