DATAJPA-181 - Improve JPAQuery instantiation for Querydsl support.

Upgraded to Querydsl 2.3.3. We now choose the appropriate JPQLTemplate depending on the used persistence provider inside QueryDslRepositorySupport as well as QueryDslJpaRepository.

pom.xml

@@ -60,7 +60,7 @@
 		<openjpa.version>2.1.1</openjpa.version>
 		<eclipselink.version>2.3.2</eclipselink.version>
 		<aspectj.version>1.6.12</aspectj.version>
-		<querydsl.version>2.3.0</querydsl.version>
+		<querydsl.version>2.3.3</querydsl.version>
 		<junit.version>4.8.1</junit.version>
 		<jpa.version>2.0.0</jpa.version>
 		<slf4j.version>1.6.1</slf4j.version>

src/main/java/org/springframework/data/jpa/repository/support/QueryDslJpaRepository.java

@@ -30,7 +30,6 @@ import org.springframework.data.querydsl.QueryDslPredicateExecutor;
 import org.springframework.data.querydsl.SimpleEntityPathResolver;
 
 import com.mysema.query.jpa.JPQLQuery;
-import com.mysema.query.jpa.impl.JPAQuery;
 import com.mysema.query.types.EntityPath;
 import com.mysema.query.types.Expression;
 import com.mysema.query.types.OrderSpecifier;
@@ -51,6 +50,7 @@ public class QueryDslJpaRepository<T, ID extends Serializable> extends SimpleJpa
 	private final EntityManager em;
 	private final EntityPath<T> path;
 	private final PathBuilder<T> builder;
+	private final PersistenceProvider provider;
 
 	/**
 	 * Creates a new {@link QueryDslJpaRepository} from the given domain class and {@link EntityManager}. This will use
@@ -79,6 +79,7 @@ public class QueryDslJpaRepository<T, ID extends Serializable> extends SimpleJpa
 		this.em = entityManager;
 		this.path = resolver.createPath(entityMetadata.getJavaType());
 		this.builder = new PathBuilder<T>(path.getType(), path.getMetadata());
+		this.provider = PersistenceProvider.fromEntityManager(entityManager);
 	}
 
 	/*
@@ -148,8 +149,7 @@ public class QueryDslJpaRepository<T, ID extends Serializable> extends SimpleJpa
 	 * @return
 	 */
 	protected JPQLQuery createQuery(Predicate... predicate) {
-
-		return new JPAQuery(em).from(path).where(predicate);
+		return QuerydslUtils.createQueryInstance(em, provider).from(path).where(predicate);
 	}
 
 	/**

src/main/java/org/springframework/data/jpa/repository/support/QueryDslRepositorySupport.java

@@ -26,7 +26,6 @@ import com.mysema.query.dml.DeleteClause;
 import com.mysema.query.dml.UpdateClause;
 import com.mysema.query.jpa.JPQLQuery;
 import com.mysema.query.jpa.impl.JPADeleteClause;
-import com.mysema.query.jpa.impl.JPAQuery;
 import com.mysema.query.jpa.impl.JPAUpdateClause;
 import com.mysema.query.types.EntityPath;
 import com.mysema.query.types.path.PathBuilder;
@@ -40,8 +39,9 @@ import com.mysema.query.types.path.PathBuilderFactory;
 @Repository
 public abstract class QueryDslRepositorySupport {
 
-	private EntityManager entityManager;
 	private PathBuilderFactory builderFactory = new PathBuilderFactory();
+	private EntityManager entityManager;
+	private PersistenceProvider provider;
 
 	/**
 	 * Setter to inject {@link EntityManager}.
@@ -53,6 +53,7 @@ public abstract class QueryDslRepositorySupport {
 
 		Assert.notNull(entityManager);
 		this.entityManager = entityManager;
+		this.provider = PersistenceProvider.fromEntityManager(entityManager);
 	}
 
 	/**
@@ -78,8 +79,7 @@ public abstract class QueryDslRepositorySupport {
 	 * @return
 	 */
 	protected JPQLQuery from(EntityPath<?>... paths) {
-
-		return new JPAQuery(entityManager).from(paths);
+		return QuerydslUtils.createQueryInstance(entityManager, provider).from(paths);
 	}
 
 	/**

src/main/java/org/springframework/data/jpa/repository/support/QuerydslUtils.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2012 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.jpa.repository.support;
+
+import javax.persistence.EntityManager;
+
+import com.mysema.query.jpa.EclipseLinkTemplates;
+import com.mysema.query.jpa.HQLTemplates;
+import com.mysema.query.jpa.JPQLQuery;
+import com.mysema.query.jpa.OpenJPATemplates;
+import com.mysema.query.jpa.impl.JPAQuery;
+
+/**
+ * Utility methods for Querydsl.
+ * 
+ * @author Oliver Gierke
+ */
+class QuerydslUtils {
+
+	/**
+	 * Creates the {@link JPQLQuery} instance based on the given {@link EntityManager} and {@link PersistenceProvider}.
+	 * 
+	 * @return
+	 */
+	public static JPQLQuery createQueryInstance(EntityManager em, PersistenceProvider provider) {
+
+		switch (provider) {
+		case ECLIPSELINK:
+			return new JPAQuery(em, EclipseLinkTemplates.DEFAULT);
+		case HIBERNATE:
+			return new JPAQuery(em, HQLTemplates.DEFAULT);
+		case OPEN_JPA:
+			return new JPAQuery(em, OpenJPATemplates.DEFAULT);
+		case GENERIC_JPA:
+		default:
+			return new JPAQuery(em);
+		}
+	}
+}