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1   /*
2    * Copyright 2006-2012 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.sample.common;
18  
19  import javax.sql.DataSource;
20  
21  import org.springframework.batch.core.listener.StepListenerSupport;
22  import org.springframework.batch.item.ItemReader;
23  import org.springframework.beans.factory.InitializingBean;
24  import org.springframework.dao.OptimisticLockingFailureException;
25  import org.springframework.jdbc.core.JdbcOperations;
26  import org.springframework.jdbc.core.JdbcTemplate;
27  import org.springframework.util.Assert;
28  
29  /**
30   * Thread-safe database {@link ItemReader} implementing the process indicator
31   * pattern.
32   */
33  public class StagingItemListener extends StepListenerSupport<Long, Long> implements InitializingBean {
34  
35  	private JdbcOperations jdbcTemplate;
36  
37  	public void setDataSource(DataSource dataSource) {
38  		jdbcTemplate = new JdbcTemplate(dataSource);
39  	}
40  
41  	public final void afterPropertiesSet() throws Exception {
42  		Assert.notNull(jdbcTemplate, "You must provide a DataSource.");
43  	}
44  
45  	@Override
46  	public void afterRead(Long id) {
47  		int count = jdbcTemplate.update("UPDATE BATCH_STAGING SET PROCESSED=? WHERE ID=? AND PROCESSED=?",
48  				StagingItemWriter.DONE, id, StagingItemWriter.NEW);
49  		if (count != 1) {
50  			throw new OptimisticLockingFailureException("The staging record with ID=" + id
51  					+ " was updated concurrently when trying to mark as complete (updated " + count + " records.");
52  		}
53  	}
54  
55  }