/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.ode.dao.jpa;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.openjpa.persistence.OpenJPAPersistence;
import org.apache.openjpa.persistence.OpenJPAQuery;
import javax.persistence.EntityManager;
import javax.persistence.Query;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
/**
* @author Matthieu Riou <mriou at apache dot org>
*/
public class OpenJPADAO {
private static final Log __log = LogFactory.getLog(OpenJPADAO.class);
protected BPELDAOConnectionImpl getConn() {
return BPELDAOConnectionFactoryImpl._connections.get();
}
protected EntityManager getEM() {
return OpenJPAPersistence.getEntityManager(this);
}
/**
* javax.persistence.Query either let you query for a collection or a single
* value throwing an exception if nothing is found. Just a convenient shortcut
* for single results allowing null values
* @param qry query to execute
* @return whatever you assign it to
*/
@SuppressWarnings("unchecked")
protected <T> T getSingleResult(Query qry) {
List res = qry.getResultList();
if (res.size() == 0) return null;
return (T) res.get(0);
}
protected <T> void batchUpdateByIds(Iterator<T> ids, Query query, String parameterName) {
if( query instanceof OpenJPAQuery ) {
OpenJPAQuery openJpaQuery = (OpenJPAQuery)query;
int batchSize = openJpaQuery.getFetchPlan().getFetchBatchSize();
if(batchSize <= 0 ) {
batchSize = 50;
if(__log.isTraceEnabled()) __log.trace("JPA Query fetchBatchSize=-1, so defaults to 50.");
} else {
if( __log.isTraceEnabled() ) __log.trace("BATCH fetchBatchSize = " + batchSize);
}
List<T> batch = new ArrayList<T>();
while( ids.hasNext() ) {
for( int i = 0; i < batchSize && ids.hasNext(); i++ ) {
batch.add(ids.next());
}
if( __log.isTraceEnabled() ) __log.trace("BATCH updating " + batch.size() + " objects.");
query.setParameter(parameterName, batch);
query.executeUpdate();
batch.clear();
}
}
}
}