DATADOC-90 - Refactored PartTreeJpaQuery to create new JpaQueryCreator on every query recreation.

JpaQueryCreator is stateful as we create a list of ParameterExpressions and iterate over them. So we have to re-instantiate the JpaQueryCreator to not create an exception on the second attempt.

src/main/java/org/springframework/data/jpa/repository/query/PartTreeJpaQuery.java

@@ -27,7 +27,6 @@ import org.springframework.data.domain.Sort;
 import org.springframework.data.repository.query.Parameters;
 import org.springframework.data.repository.query.ParametersParameterAccessor;
 import org.springframework.data.repository.query.parser.PartTree;
-import org.springframework.util.Assert;
 
 
 /**
@@ -59,8 +58,8 @@ public class PartTreeJpaQuery extends AbstractJpaQuery {
         this.tree = new PartTree(method.getName(), domainClass);
         this.parameters = method.getParameters();
 
-        this.query = new QueryPreparer(tree, domainClass, parameters);
-        this.countQuery = new CountQueryPreparer(tree, domainClass, parameters);
+        this.query = new QueryPreparer();
+        this.countQuery = new CountQueryPreparer();
     }
 
 
@@ -100,37 +99,7 @@ public class PartTreeJpaQuery extends AbstractJpaQuery {
     private class QueryPreparer {
 
         private CriteriaQuery<?> query;
-        private final JpaQueryCreator creator;
-
-
-        /**
-         * Creates a new {@link QueryPreparer} from the given {@link PartTree},
-         * domain class and {@link Parameters}.
-         * 
-         * @param tree
-         * @param domainClass
-         * @param parameters
-         */
-        public QueryPreparer(PartTree tree, Class<?> domainClass,
-                Parameters parameters) {
-
-            this(new JpaQueryCreator(tree, domainClass, parameters,
-                    getEntityManager()));
-        }
-
-
-        /**
-         * Creates a new {@link QueryPreparer} from the given
-         * {@link JpaQueryCreator}.
-         * 
-         * @param creator must not be {@literl null}.
-         */
-        protected QueryPreparer(JpaQueryCreator creator) {
-
-            Assert.notNull(creator);
-            this.creator = creator;
-            this.query = null;
-        }
+        private JpaQueryCreator creator;
 
 
         /**
@@ -141,7 +110,9 @@ public class PartTreeJpaQuery extends AbstractJpaQuery {
          */
         public Query createQuery(Object[] values) {
 
-            if (parameters.potentiallySortsDynamically() || query == null) {
+            if (parameters.potentiallySortsDynamically() || query == null
+                    || creator == null) {
+                creator = createCreator();
                 query = creator.createQuery(getDynamicSort(values));
             }
 
@@ -152,6 +123,13 @@ public class PartTreeJpaQuery extends AbstractJpaQuery {
         }
 
 
+        protected JpaQueryCreator createCreator() {
+
+            return new JpaQueryCreator(tree, domainClass, parameters,
+                    getEntityManager());
+        }
+
+
         /**
          * Invokes parameter binding on the given {@link TypedQuery}.
          * 
@@ -188,20 +166,17 @@ public class PartTreeJpaQuery extends AbstractJpaQuery {
      */
     private class CountQueryPreparer extends QueryPreparer {
 
-        /**
-         * Creates a new {@link CountQueryPreparer} from the given
-         * {@link PartTree}, domain class and {@link Parameters}. Will use a
-         * {@link JpaCountQueryCreator} to create the query.
+        /*
+         * (non-Javadoc)
          * 
-         * @param tree
-         * @param domainClass
-         * @param parameters
+         * @see org.springframework.data.jpa.repository.query.PartTreeJpaQuery.
+         * QueryPreparer#createCreator()
          */
-        public CountQueryPreparer(PartTree tree, Class<?> domainClass,
-                Parameters parameters) {
+        @Override
+        protected JpaQueryCreator createCreator() {
 
-            super(new JpaCountQueryCreator(tree, domainClass, parameters,
-                    getEntityManager()));
+            return new JpaCountQueryCreator(tree, domainClass, parameters,
+                    getEntityManager());
         }
 
 

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

@@ -31,7 +31,7 @@ import org.springframework.data.jpa.repository.query.QueryExtractor;
  * 
  * @author Oliver Gierke
  */
-enum PersistenceProvider implements QueryExtractor {
+public enum PersistenceProvider implements QueryExtractor {
 
     /**
      * Hibernate persistence provider.

src/test/java/org/springframework/data/jpa/repository/query/PartTreeJpaQueryIntegrationTests.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2011 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.query;
+
+import java.lang.reflect.Method;
+
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.PageRequest;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.jpa.domain.sample.User;
+import org.springframework.data.jpa.repository.support.PersistenceProvider;
+import org.springframework.data.repository.Repository;
+import org.springframework.data.repository.core.support.DefaultRepositoryMetadata;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+
+/**
+ * Integration tests for {@link PartTreeJpaQuery}.
+ * 
+ * @author Oliver Gierke
+ */
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration("classpath:infrastructure.xml")
+public class PartTreeJpaQueryIntegrationTests {
+
+    @PersistenceContext
+    EntityManager entityManager;
+
+
+    /**
+     * @see DATADOC-90
+     * @throws Exception
+     */
+    @Test
+    public void test() throws Exception {
+
+        Method method =
+                UserRepository.class.getMethod("findByFirstname", String.class,
+                        Pageable.class);
+        JpaQueryMethod queryMethod =
+                new JpaQueryMethod(method, new DefaultRepositoryMetadata(
+                        UserRepository.class),
+                        PersistenceProvider.fromEntityManager(entityManager));
+        PartTreeJpaQuery jpaQuery =
+                new PartTreeJpaQuery(queryMethod, entityManager);
+
+        jpaQuery.createQuery(new Object[] { "Matthews", new PageRequest(0, 1) });
+        jpaQuery.createQuery(new Object[] { "Matthews", new PageRequest(0, 1) });
+    }
+
+    interface UserRepository extends Repository<User, Long> {
+
+        Page<User> findByFirstname(String firstname, Pageable pageable);
+    }
+}