/*
* Copyright 2010-2013 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.mybatis.spring.batch;
import static org.springframework.util.Assert.notNull;
import static org.springframework.util.ClassUtils.getShortName;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.CopyOnWriteArrayList;
import org.apache.ibatis.session.ExecutorType;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionTemplate;
import org.springframework.batch.item.database.AbstractPagingItemReader;
/**
* {@code org.springframework.batch.item.ItemReader} for reading database
* records using MyBatis in a paging fashion.
* <p>
* Provided to facilitate the migration from Spring-Batch iBATIS 2 page item readers to MyBatis 3.
*
* @author Eduardo Macarron
*
* @since 1.1.0
* @version $Id$
*/
public class MyBatisPagingItemReader<T> extends AbstractPagingItemReader<T> {
private String queryId;
private SqlSessionFactory sqlSessionFactory;
private SqlSessionTemplate sqlSessionTemplate;
private Map<String, Object> parameterValues;
public MyBatisPagingItemReader() {
setName(getShortName(MyBatisPagingItemReader.class));
}
/**
* Public setter for {@link SqlSessionFactory} for injection purposes.
*
* @param SqlSessionFactory sqlSessionFactory
*/
public void setSqlSessionFactory(SqlSessionFactory sqlSessionFactory) {
this.sqlSessionFactory = sqlSessionFactory;
}
/**
* Public setter for the statement id identifying the statement in the SqlMap
* configuration file.
*
* @param queryId the id for the statement
*/
public void setQueryId(String queryId) {
this.queryId = queryId;
}
/**
* The parameter values to be used for the query execution.
*
* @param parameterValues the values keyed by the parameter named used in
* the query string.
*/
public void setParameterValues(Map<String, Object> parameterValues) {
this.parameterValues = parameterValues;
}
/**
* Check mandatory properties.
* @see org.springframework.beans.factory.InitializingBean#afterPropertiesSet()
*/
@Override
public void afterPropertiesSet() throws Exception {
super.afterPropertiesSet();
notNull(sqlSessionFactory);
sqlSessionTemplate = new SqlSessionTemplate(sqlSessionFactory, ExecutorType.BATCH);
notNull(queryId);
}
@Override
protected void doReadPage() {
Map<String, Object> parameters = new HashMap<String, Object>();
if (parameterValues != null) {
parameters.putAll(parameterValues);
}
parameters.put("_page", getPage());
parameters.put("_pagesize", getPageSize());
parameters.put("_skiprows", getPage() * getPageSize());
if (results == null) {
results = new CopyOnWriteArrayList<T>();
} else {
results.clear();
}
results.addAll(sqlSessionTemplate.<T> selectList(queryId, parameters));
}
@Override
protected void doJumpToPage(int itemIndex) {
// Not Implemented
}
}