001/*
002 * Copyright 2006-2008 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.batch.item.database.orm;
018
019import org.hibernate.query.NativeQuery;
020import org.hibernate.query.Query;
021
022import org.springframework.util.Assert;
023import org.springframework.util.StringUtils;
024
025/**
026 * <p>
027 * This query provider creates Hibernate {@link Query}s from injected native SQL
028 * queries. This is useful if there is a need to utilize database-specific
029 * features such as query hints, the CONNECT keyword in Oracle, etc.
030 * </p>
031 * 
032 * @author Anatoly Polinsky
033 * 
034 * @param <E> entity returned by executing the query
035 */
036public class HibernateNativeQueryProvider<E> extends AbstractHibernateQueryProvider<E> {
037
038        private String sqlQuery;
039
040        private Class<E> entityClass;
041
042        /**
043         * <p>
044         * Create an {@link NativeQuery} from the session provided (preferring
045         * stateless if both are available).
046         * </p>
047         */
048    @Override
049        @SuppressWarnings("unchecked")
050        public NativeQuery<E> createQuery() {
051
052                if (isStatelessSession()) {
053                        return getStatelessSession().createNativeQuery(sqlQuery).addEntity(entityClass);
054                }
055                else {
056                        return getStatefulSession().createNativeQuery(sqlQuery).addEntity(entityClass);
057                }
058        }
059
060        public void setSqlQuery(String sqlQuery) {
061                this.sqlQuery = sqlQuery;
062        }
063
064        public void setEntityClass(Class<E> entityClazz) {
065                this.entityClass = entityClazz;
066        }
067
068        public void afterPropertiesSet() throws Exception {
069                Assert.isTrue(StringUtils.hasText(sqlQuery), "Native SQL query cannot be empty");
070                Assert.notNull(entityClass, "Entity class cannot be NULL");
071        }
072}