Support collection parameters in @query methods.

Original Pull Request #1856 
Closes #1858

Author: herder

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

@@ -15,15 +15,18 @@
  */
 package org.springframework.data.elasticsearch.repository.support;
 
+import java.util.Collection;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
+import java.util.stream.Collectors;
 
 import org.springframework.core.convert.support.GenericConversionService;
 import org.springframework.data.repository.query.ParameterAccessor;
 import org.springframework.util.NumberUtils;
 
 /**
  * @author Peter-Josef Meisch
+ * @author Niklas Herder
  */
 final public class StringQueryUtil {
 
@@ -53,6 +56,28 @@ private static String getParameterWithIndex(ParameterAccessor accessor, int inde
 		// noinspection ConstantConditions
 		if (parameter != null) {
 
+			parameterValue = convert(parameter);
+		}
+
+		return parameterValue;
+
+	}
+
+	private static String convert(Object parameter) {
+		if (Collection.class.isAssignableFrom(parameter.getClass())) {
+			Collection<?> collectionParam = (Collection<?>) parameter;
+			StringBuilder sb = new StringBuilder("[");
+			sb.append(collectionParam.stream().map(o -> {
+				if (o instanceof String) {
+					return "\"" + convert(o) + "\"";
+				} else {
+					return convert(o);
+				}
+			}).collect(Collectors.joining(",")));
+			sb.append("]");
+			return sb.toString();
+		} else {
+			String parameterValue = "null";
 			if (conversionService.canConvert(parameter.getClass(), String.class)) {
 				String converted = conversionService.convert(parameter, String.class);
 
@@ -62,11 +87,10 @@ private static String getParameterWithIndex(ParameterAccessor accessor, int inde
 			} else {
 				parameterValue = parameter.toString();
 			}
-		}
-
-		parameterValue = parameterValue.replaceAll("\"", Matcher.quoteReplacement("\\\""));
-		return parameterValue;
 
+			parameterValue = parameterValue.replaceAll("\"", Matcher.quoteReplacement("\\\""));
+			return parameterValue;
+		}
 	}
 
 }

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

@@ -18,6 +18,7 @@
 import static org.assertj.core.api.Assertions.*;
 
 import java.lang.reflect.Method;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.HashMap;
@@ -51,6 +52,7 @@
 /**
  * @author Christoph Strobl
  * @author Peter-Josef Meisch
+ * @author Niklas Herder
  */
 @ExtendWith(MockitoExtension.class)
 public class ElasticsearchStringQueryUnitTests {
@@ -95,14 +97,50 @@ 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 // #1858
+	@DisplayName("should only quote String query parameters")
+	void shouldOnlyEscapeStringQueryParameters() throws Exception {
+		org.springframework.data.elasticsearch.core.query.Query query = createQuery("findByAge", Integer.valueOf(30));
+
+		assertThat(query).isInstanceOf(StringQuery.class);
+		assertThat(((StringQuery) query).getSource()).isEqualTo("{ 'bool' : { 'must' : { 'term' : { 'age' : 30 } } } }");
+
+	}
+
+	@Test // #1858
+	@DisplayName("should only quote String collection query parameters")
+	void shouldOnlyEscapeStringCollectionQueryParameters() throws Exception {
+		org.springframework.data.elasticsearch.core.query.Query query = createQuery("findByAgeIn",
+				new ArrayList<>(Arrays.asList(30, 35, 40)));
+
+		assertThat(query).isInstanceOf(StringQuery.class);
+		assertThat(((StringQuery) query).getSource())
+				.isEqualTo("{ 'bool' : { 'must' : { 'term' : { 'age' : [30,35,40] } } } }");
+
+	}
+
+	@Test // #1858
+	@DisplayName("should escape Strings in collection query parameters")
+	void shouldEscapeStringsInCollectionsQueryParameters() throws Exception {
+
+		final List<String> another_string = Arrays.asList("hello \"Stranger\"", "Another string");
+		List<String> params = new ArrayList<>(another_string);
+		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' : [\"hello \\\"Stranger\\\"\",\"Another string\"] } } } }");
+	}
+
+	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);
 		ElasticsearchQueryMethod queryMethod = getQueryMethod(methodName, argTypes);
 		ElasticsearchStringQuery elasticsearchStringQuery = queryForMethod(queryMethod);
 		return elasticsearchStringQuery.createQuery(new ElasticsearchParametersParameterAccessor(queryMethod, args));
 	}
+
 	private ElasticsearchStringQuery queryForMethod(ElasticsearchQueryMethod queryMethod) {
 		return new ElasticsearchStringQuery(queryMethod, operations, queryMethod.getAnnotatedQuery());
 	}
@@ -116,9 +154,18 @@ private ElasticsearchQueryMethod getQueryMethod(String name, Class<?>... paramet
 
 	private interface SampleRepository extends Repository<Person, String> {
 
+		@Query("{ 'bool' : { 'must' : { 'term' : { 'age' : ?0 } } } }")
+		List<Person> findByAge(Integer age);
+
+		@Query("{ 'bool' : { 'must' : { 'term' : { 'age' : ?0 } } } }")
+		List<Person> findByAgeIn(ArrayList<Integer> age);
+
 		@Query("{ 'bool' : { 'must' : { 'term' : { 'name' : '?0' } } } }")
 		Person findByName(String name);
 
+		@Query("{ 'bool' : { 'must' : { 'terms' : { 'name' : ?0 } } } }")
+		Person findByNameIn(ArrayList<String> names);
+
 		@Query(value = "name:(?0, ?11, ?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, ?11, ?0, ?1)")
 		Person findWithRepeatedPlaceholder(String arg0, String arg1, String arg2, String arg3, String arg4, String arg5,
 				String arg6, String arg7, String arg8, String arg9, String arg10, String arg11);
@@ -131,16 +178,27 @@ Person findWithRepeatedPlaceholder(String arg0, String arg1, String arg2, String
 	 * @author Rizwan Idrees
 	 * @author Mohsin Husen
 	 * @author Artur Konczak
+   * @author Niklas Herder
 	 */
 
 	@Document(indexName = "test-index-person-query-unittest")
 	static class Person {
 
+		@Nullable public int age;
 		@Nullable @Id private String id;
 		@Nullable private String name;
 		@Nullable @Field(type = FieldType.Nested) private List<Car> car;
 		@Nullable @Field(type = FieldType.Nested, includeInParent = true) private List<Book> books;
 
+		@Nullable
+		public int getAge() {
+			return age;
+		}
+
+		public void setAge(int age) {
+			this.age = age;
+		}
+
 		@Nullable
 		public String getId() {
 			return id;