Use registered converters for parameters of @Query annotated methods.

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

@@ -102,7 +102,8 @@ public Object execute(Object[] parameters) {
 	}
 
 	protected StringQuery createQuery(ParametersParameterAccessor parameterAccessor) {
-		String queryString = StringQueryUtil.replacePlaceholders(this.query, parameterAccessor);
+		String queryString = new StringQueryUtil(elasticsearchOperations.getElasticsearchConverter().getConversionService())
+				.replacePlaceholders(this.query, parameterAccessor);
 		return new StringQuery(queryString);
 	}
 

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

@@ -47,7 +47,9 @@ public ReactiveElasticsearchStringQuery(String query, ReactiveElasticsearchQuery
 
 	@Override
 	protected StringQuery createQuery(ElasticsearchParameterAccessor parameterAccessor) {
-		String queryString = StringQueryUtil.replacePlaceholders(this.query, parameterAccessor);
+		String queryString = new StringQueryUtil(
+				getElasticsearchOperations().getElasticsearchConverter().getConversionService()).replacePlaceholders(this.query,
+						parameterAccessor);
 		return new StringQuery(queryString);
 	}
 

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

@@ -20,7 +20,7 @@
 import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 
-import org.springframework.core.convert.support.GenericConversionService;
+import org.springframework.core.convert.ConversionService;
 import org.springframework.data.repository.query.ParameterAccessor;
 import org.springframework.util.NumberUtils;
 
@@ -31,11 +31,14 @@
 final public class StringQueryUtil {
 
 	private static final Pattern PARAMETER_PLACEHOLDER = Pattern.compile("\\?(\\d+)");
-	private static final GenericConversionService conversionService = new GenericConversionService();
 
-	private StringQueryUtil() {}
+	private final ConversionService conversionService;
 
-	public static String replacePlaceholders(String input, ParameterAccessor accessor) {
+	public StringQueryUtil(ConversionService conversionService) {
+		this.conversionService = conversionService;
+	}
+
+	public String replacePlaceholders(String input, ParameterAccessor accessor) {
 
 		Matcher matcher = PARAMETER_PLACEHOLDER.matcher(input);
 		String result = input;
@@ -48,7 +51,7 @@ public static String replacePlaceholders(String input, ParameterAccessor accesso
 		return result;
 	}
 
-	private static String getParameterWithIndex(ParameterAccessor accessor, int index) {
+	private String getParameterWithIndex(ParameterAccessor accessor, int index) {
 
 		Object parameter = accessor.getBindableValue(index);
 		String parameterValue = "null";
@@ -63,7 +66,7 @@ private static String getParameterWithIndex(ParameterAccessor accessor, int inde
 
 	}
 
-	private static String convert(Object parameter) {
+	private String convert(Object parameter) {
 		if (Collection.class.isAssignableFrom(parameter.getClass())) {
 			Collection<?> collectionParam = (Collection<?>) parameter;
 			StringBuilder sb = new StringBuilder("[");

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

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2021 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.elasticsearch.repository.query;
+
+import java.util.ArrayList;
+import java.util.Collection;
+
+import org.springframework.core.convert.converter.Converter;
+import org.springframework.data.convert.CustomConversions;
+import org.springframework.data.elasticsearch.core.convert.ElasticsearchConverter;
+import org.springframework.data.elasticsearch.core.convert.ElasticsearchCustomConversions;
+import org.springframework.data.elasticsearch.core.convert.MappingElasticsearchConverter;
+import org.springframework.data.elasticsearch.core.mapping.SimpleElasticsearchMappingContext;
+import org.springframework.lang.Nullable;
+
+/**
+ * @author Peter-Josef Meisch
+ */
+public class ElasticsearchStringQueryUnitTestBase {
+
+	protected ElasticsearchConverter setupConverter() {
+		MappingElasticsearchConverter converter = new MappingElasticsearchConverter(
+				new SimpleElasticsearchMappingContext());
+		Collection<Converter<?, ?>> converters = new ArrayList<>();
+		converters.add(ElasticsearchStringQueryUnitTests.CarConverter.INSTANCE);
+		CustomConversions customConversions = new ElasticsearchCustomConversions(converters);
+		converter.setConversions(customConversions);
+		converter.afterPropertiesSet();
+		return converter;
+	}
+
+	static class Car {
+		@Nullable private String name;
+		@Nullable private String model;
+
+		@Nullable
+		public String getName() {
+			return name;
+		}
+
+		public void setName(@Nullable String name) {
+			this.name = name;
+		}
+
+		@Nullable
+		public String getModel() {
+			return model;
+		}
+
+		public void setModel(@Nullable String model) {
+			this.model = model;
+		}
+	}
+
+	enum CarConverter implements Converter<Car, String> {
+		INSTANCE;
+
+		@Override
+		public String convert(ElasticsearchStringQueryUnitTests.Car car) {
+			return (car.getName() != null ? car.getName() : "null") + '-'
+					+ (car.getModel() != null ? car.getModel() : "null");
+		}
+	}
+
+}

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

@@ -16,6 +16,7 @@
 package org.springframework.data.elasticsearch.repository.query;
 
 import static org.assertj.core.api.Assertions.*;
+import static org.mockito.Mockito.*;
 
 import java.lang.reflect.Method;
 import java.util.ArrayList;
@@ -40,9 +41,6 @@
 import org.springframework.data.elasticsearch.annotations.Query;
 import org.springframework.data.elasticsearch.core.ElasticsearchOperations;
 import org.springframework.data.elasticsearch.core.SearchHits;
-import org.springframework.data.elasticsearch.core.convert.ElasticsearchConverter;
-import org.springframework.data.elasticsearch.core.convert.MappingElasticsearchConverter;
-import org.springframework.data.elasticsearch.core.mapping.SimpleElasticsearchMappingContext;
 import org.springframework.data.elasticsearch.core.query.StringQuery;
 import org.springframework.data.projection.SpelAwareProxyProjectionFactory;
 import org.springframework.data.repository.Repository;
@@ -55,14 +53,13 @@
  * @author Niklas Herder
  */
 @ExtendWith(MockitoExtension.class)
-public class ElasticsearchStringQueryUnitTests {
+public class ElasticsearchStringQueryUnitTests extends ElasticsearchStringQueryUnitTestBase {
 
 	@Mock ElasticsearchOperations operations;
-	ElasticsearchConverter converter;
 
 	@BeforeEach
 	public void setUp() {
-		converter = new MappingElasticsearchConverter(new SimpleElasticsearchMappingContext());
+		when(operations.getElasticsearchConverter()).thenReturn(setupConverter());
 	}
 
 	@Test // DATAES-552
@@ -141,6 +138,21 @@ private org.springframework.data.elasticsearch.core.query.Query createQuery(Stri
 		return elasticsearchStringQuery.createQuery(new ElasticsearchParametersParameterAccessor(queryMethod, args));
 	}
 
+	@Test // #1866
+	@DisplayName("should use converter on parameters")
+	void shouldUseConverterOnParameters() throws NoSuchMethodException {
+
+		Car car = new Car();
+		car.setName("Toyota");
+		car.setModel("Prius");
+
+		org.springframework.data.elasticsearch.core.query.Query query = createQuery("findByCar", car);
+
+		assertThat(query).isInstanceOf(StringQuery.class);
+		assertThat(((StringQuery) query).getSource())
+				.isEqualTo("{ 'bool' : { 'must' : { 'term' : { 'car' : 'Toyota-Prius' } } } }");
+	}
+
 	private ElasticsearchStringQuery queryForMethod(ElasticsearchQueryMethod queryMethod) {
 		return new ElasticsearchStringQuery(queryMethod, operations, queryMethod.getAnnotatedQuery());
 	}
@@ -149,7 +161,7 @@ private ElasticsearchQueryMethod getQueryMethod(String name, Class<?>... paramet
 
 		Method method = SampleRepository.class.getMethod(name, parameters);
 		return new ElasticsearchQueryMethod(method, new DefaultRepositoryMetadata(SampleRepository.class),
-				new SpelAwareProxyProjectionFactory(), converter.getMappingContext());
+				new SpelAwareProxyProjectionFactory(), operations.getElasticsearchConverter().getMappingContext());
 	}
 
 	private interface SampleRepository extends Repository<Person, String> {
@@ -172,13 +184,16 @@ Person findWithRepeatedPlaceholder(String arg0, String arg1, String arg2, String
 
 		@Query("{\"bool\":{\"must\": [{\"match\": {\"prefix\": {\"name\" : \"?0\"}}]}}")
 		SearchHits<Book> findByPrefix(String prefix);
+
+		@Query("{ 'bool' : { 'must' : { 'term' : { 'car' : '?0' } } } }")
+		Person findByCar(Car car);
 	}
 
 	/**
 	 * @author Rizwan Idrees
 	 * @author Mohsin Husen
 	 * @author Artur Konczak
-   * @author Niklas Herder
+	 * @author Niklas Herder
 	 */
 
 	@Document(indexName = "test-index-person-query-unittest")
@@ -292,29 +307,6 @@ public void setDescription(@Nullable String description) {
 		}
 	}
 
-	static class Car {
-		@Nullable private String name;
-		@Nullable private String model;
-
-		@Nullable
-		public String getName() {
-			return name;
-		}
-
-		public void setName(@Nullable String name) {
-			this.name = name;
-		}
-
-		@Nullable
-		public String getModel() {
-			return model;
-		}
-
-		public void setModel(@Nullable String model) {
-			this.model = model;
-		}
-	}
-
 	static class Author {
 
 		@Nullable private String id;
@@ -338,5 +330,4 @@ public void setName(String name) {
 			this.name = name;
 		}
 	}
-
 }

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

@@ -16,6 +16,7 @@
 package org.springframework.data.elasticsearch.repository.query;
 
 import static org.assertj.core.api.Assertions.*;
+import static org.mockito.Mockito.*;
 
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
@@ -43,9 +44,6 @@
 import org.springframework.data.elasticsearch.annotations.Query;
 import org.springframework.data.elasticsearch.core.ReactiveElasticsearchOperations;
 import org.springframework.data.elasticsearch.core.SearchHit;
-import org.springframework.data.elasticsearch.core.convert.ElasticsearchConverter;
-import org.springframework.data.elasticsearch.core.convert.MappingElasticsearchConverter;
-import org.springframework.data.elasticsearch.core.mapping.SimpleElasticsearchMappingContext;
 import org.springframework.data.elasticsearch.core.query.StringQuery;
 import org.springframework.data.projection.SpelAwareProxyProjectionFactory;
 import org.springframework.data.repository.Repository;
@@ -59,16 +57,15 @@
  * @author Peter-Josef Meisch
  */
 @ExtendWith(MockitoExtension.class)
-public class ReactiveElasticsearchStringQueryUnitTests {
+public class ReactiveElasticsearchStringQueryUnitTests extends ElasticsearchStringQueryUnitTestBase {
 
 	SpelExpressionParser PARSER = new SpelExpressionParser();
-	ElasticsearchConverter converter;
 
 	@Mock ReactiveElasticsearchOperations operations;
 
 	@BeforeEach
 	public void setUp() {
-		converter = new MappingElasticsearchConverter(new SimpleElasticsearchMappingContext());
+		when(operations.getElasticsearchConverter()).thenReturn(setupConverter());
 	}
 
 	@Test // DATAES-519
@@ -132,7 +129,22 @@ void shouldEscapeStringsInQueryParameters() throws Exception {
 				.isEqualTo("{\"bool\":{\"must\": [{\"match\": {\"prefix\": {\"name\" : \"hello \\\"Stranger\\\"\"}}]}}");
 	}
 
-	private org.springframework.data.elasticsearch.core.query.Query createQuery(String methodName, String... args)
+	@Test // #1866
+	@DisplayName("should use converter on parameters")
+	void shouldUseConverterOnParameters() throws Exception {
+
+		Car car = new Car();
+		car.setName("Toyota");
+		car.setModel("Prius");
+
+		org.springframework.data.elasticsearch.core.query.Query query = createQuery("findByCar", car);
+
+		assertThat(query).isInstanceOf(StringQuery.class);
+		assertThat(((StringQuery) query).getSource())
+				.isEqualTo("{ 'bool' : { 'must' : { 'term' : { 'car' : 'Toyota-Prius' } } } }");
+	}
+
+	private org.springframework.data.elasticsearch.core.query.Query createQuery(String methodName, Object... args)
 			throws NoSuchMethodException {
 
 		Class<?>[] argTypes = Arrays.stream(args).map(Object::getClass).toArray(Class[]::new);
@@ -152,7 +164,7 @@ private ReactiveElasticsearchQueryMethod getQueryMethod(String name, Class<?>...
 
 		Method method = SampleRepository.class.getMethod(name, parameters);
 		return new ReactiveElasticsearchQueryMethod(method, new DefaultRepositoryMetadata(SampleRepository.class),
-				new SpelAwareProxyProjectionFactory(), converter.getMappingContext());
+				new SpelAwareProxyProjectionFactory(), operations.getElasticsearchConverter().getMappingContext());
 	}
 
 	private ReactiveElasticsearchStringQuery createQueryForMethod(String name, Class<?>... parameters) throws Exception {
@@ -180,6 +192,9 @@ Person findWithRepeatedPlaceholder(String arg0, String arg1, String arg2, String
 		@Query("{\"bool\":{\"must\": [{\"match\": {\"prefix\": {\"name\" : \"?0\"}}]}}")
 		Flux<SearchHit<Book>> findByPrefix(String prefix);
 
+		@Query("{ 'bool' : { 'must' : { 'term' : { 'car' : '?0' } } } }")
+		Mono<Person> findByCar(Car car);
+
 	}
 
 	/**
@@ -292,29 +307,6 @@ public void setDescription(@Nullable String description) {
 		}
 	}
 
-	static class Car {
-		@Nullable private String name;
-		@Nullable private String model;
-
-		@Nullable
-		public String getName() {
-			return name;
-		}
-
-		public void setName(@Nullable String name) {
-			this.name = name;
-		}
-
-		@Nullable
-		public String getModel() {
-			return model;
-		}
-
-		public void setModel(@Nullable String model) {
-			this.model = model;
-		}
-	}
-
 	static class Author {
 
 		@Nullable private String id;