DATAGRAPH-1199 - Add @ExistsQuery for convenience.

spring-data-neo4j/src/main/java/org/springframework/data/neo4j/annotation/ExistsQuery.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2011-2019 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
+ *
+ *      http://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.neo4j.annotation;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import org.springframework.core.annotation.AliasFor;
+
+/**
+ * Annotation to declare a {@link Query} with a value containing an exists custom query. The result will then be used for
+ * boolean projection.
+ *
+ * @author Gerrit Meier
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target({ ElementType.METHOD, ElementType.ANNOTATION_TYPE })
+@Documented
+@Query(exists = true)
+public @interface ExistsQuery {
+
+	/**
+	 * The cypher query.
+	 * 
+	 * @see Query#value()
+	 * @since 5.2
+	 */
+	@AliasFor(annotation = Query.class)
+	String value() default "";
+}

spring-data-neo4j/src/main/java/org/springframework/data/neo4j/annotation/Query.java

@@ -31,7 +31,7 @@ import org.springframework.data.annotation.QueryAnnotation;
  * @author Gerrit Meier
  */
 @Retention(RetentionPolicy.RUNTIME)
-@Target(ElementType.METHOD)
+@Target({ ElementType.ANNOTATION_TYPE, ElementType.METHOD })
 @QueryAnnotation
 @Documented
 public @interface Query {

spring-data-neo4j/src/main/java/org/springframework/data/neo4j/repository/query/GraphQueryMethod.java

@@ -50,7 +50,7 @@ public class GraphQueryMethod extends QueryMethod {
 		super(method, metadata, factory);
 
 		this.method = method;
-		this.queryAnnotation = method.getAnnotation(Query.class);
+		this.queryAnnotation = AnnotatedElementUtils.findMergedAnnotation(method, Query.class);
 		if (this.queryAnnotation != null) {
 			this.isExistsQuery = queryAnnotation.exists();
 		} else {

spring-data-neo4j/src/test/java/org/springframework/data/neo4j/examples/restaurants/RestaurantTests.java

@@ -521,6 +521,22 @@ public class RestaurantTests {
 		assertFalse(restaurantRepository.existenceOfAGoodRestaurant());
 	}
 
+	@Test // DATAGRAPH-1199
+	public void shouldCheckExistenceForExistsQueryMethod() {
+		Restaurant restaurant = new Restaurant("R1", "good");
+		restaurantRepository.save(restaurant);
+
+		assertTrue(restaurantRepository.existenceOfAGoodRestaurantWithExistsQuery());
+	}
+
+	@Test // DATAGRAPH-1199
+	public void shouldCheckNonExistenceForExistsQueryMethod() {
+		Restaurant restaurant = new Restaurant("R1", "bad");
+		restaurantRepository.save(restaurant);
+
+		assertFalse(restaurantRepository.existenceOfAGoodRestaurantWithExistsQuery());
+	}
+
 	@Configuration
 	@Neo4jIntegrationTest(domainPackages = "org.springframework.data.neo4j.examples.restaurants.domain",
 			repositoryPackages = "org.springframework.data.neo4j.examples.restaurants.repo")

spring-data-neo4j/src/test/java/org/springframework/data/neo4j/examples/restaurants/repo/RestaurantRepository.java

@@ -20,6 +20,7 @@ import java.util.List;
 
 import org.springframework.data.geo.Distance;
 import org.springframework.data.geo.Point;
+import org.springframework.data.neo4j.annotation.ExistsQuery;
 import org.springframework.data.neo4j.annotation.Query;
 import org.springframework.data.neo4j.examples.restaurants.domain.Restaurant;
 import org.springframework.data.neo4j.repository.Neo4jRepository;
@@ -85,4 +86,7 @@ public interface RestaurantRepository extends Neo4jRepository<Restaurant, Long>
 
 	@Query(value = "MATCH (r:Restaurant) WHERE r.description = 'good' return r", exists = true)
 	boolean existenceOfAGoodRestaurant();
+
+	@ExistsQuery("MATCH (r:Restaurant) WHERE r.description = 'good' return r")
+	boolean existenceOfAGoodRestaurantWithExistsQuery();
 }