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1   /*
2    * Copyright 2006-2008 the original author or authors.
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  
17  package org.springframework.batch.item.database.orm;
18  
19  import javax.persistence.Query;
20  
21  import org.springframework.util.Assert;
22  import org.springframework.util.StringUtils;
23  
24  /**
25   * <p>
26   * This query provider creates JPA {@link Query}s from injected native SQL
27   * queries. This is useful if there is a need to utilize database-specific
28   * features such as query hints, the CONNECT keyword in Oracle, etc.
29   * </p>
30   * 
31   * @author Anatoly Polinsky
32   * 
33   * @param <E> entity returned by executing the query
34   */
35  public class JpaNativeQueryProvider<E> extends AbstractJpaQueryProvider {
36  
37  	private Class<E> entityClass;
38  
39  	private String sqlQuery;
40  
41      @Override
42  	public Query createQuery() {
43  		return getEntityManager().createNativeQuery(sqlQuery, entityClass);
44  	}
45  
46  	public void setSqlQuery(String sqlQuery) {
47  		this.sqlQuery = sqlQuery;
48  	}
49  
50  	public void setEntityClass(Class<E> entityClazz) {
51  		this.entityClass = entityClazz;
52  	}
53  
54      @Override
55  	public void afterPropertiesSet() throws Exception {
56  		Assert.isTrue(StringUtils.hasText(sqlQuery), "Native SQL query cannot be empty");
57  		Assert.notNull(entityClass, "Entity class cannot be NULL");
58  	}
59  }