/*
* Seldon -- open source prediction engine
* =======================================
*
* Copyright 2011-2015 Seldon Technologies Ltd and Rummble Ltd (http://www.seldon.io/)
*
* ********************************************************************************************
*
* 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 io.seldon.similarity.item;
import io.seldon.api.Constants;
import io.seldon.db.jdo.ClientPersistable;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import javax.jdo.Query;
import org.apache.commons.lang.StringUtils;
import org.apache.log4j.Logger;
public class JdoItemSimilarityPeer extends ClientPersistable implements IItemSimilarityPeer {
private static Logger logger = Logger.getLogger( JdoItemSimilarityPeer.class.getName() );
public JdoItemSimilarityPeer(String clientName) {
super(clientName);
}
@Override
public Map<Long, Double> getSimilarItems(long itemId,Set<Integer> dimensions,int max) {
Collection<Object[]> results;
Query query;
if (dimensions.isEmpty() || (dimensions.size() == 1 && dimensions.iterator().next() == Constants.DEFAULT_DIMENSION))
{
String sql = "select isim.item_id2 as item_id,score from item_similarity isim where isim.item_id=? union select isim.item_id,score from item_similarity isim where isim.item_id2=? order by score desc";
if (max > 0)
sql = sql + " limit "+max;
query = getPM().newQuery( "javax.jdo.query.SQL", sql);
ArrayList<Object> args = new ArrayList<>();
args.add(itemId);
args.add(itemId);
results = (Collection<Object[]>) query.executeWithArray(args.toArray());
}
else
{
String dimensionsStr = StringUtils.join(dimensions, ",");
String sql = "select isim.item_id2 as item_id,score from item_similarity isim join item_map_enum ime on (isim.item_id2=ime.item_id) join dimension d on (ime.attr_id=d.attr_id and ime.value_id=d.value_id) where dim_id in ("+dimensionsStr+") and isim.item_id=? union select isim.item_id,score from item_similarity isim join item_map_enum ime on (isim.item_id=ime.item_id) join dimension d on (ime.attr_id=d.attr_id and ime.value_id=d.value_id) where dim_id in ("+dimensionsStr+") and isim.item_id2=? order by score desc";
if (max > 0)
sql = sql + " limit "+max;
query = getPM().newQuery( "javax.jdo.query.SQL", sql);
ArrayList<Object> args = new ArrayList<>();
args.add(itemId);
args.add(itemId);
results = (Collection<Object[]>) query.executeWithArray(args.toArray());
}
Map<Long,Double> map = new HashMap<>();
for(Object[] res : results)
{
Long item = (Long) res[0];
Double score = (Double) res[1];
map.put(item, score);
}
query.closeAll();
return map;
}
@Override
public Map<Long, Double> getRecommendations(long userId, int dimension, int max) {
String sql = "select r.item_id,score from recommendations r join item_map_enum ime on (r.item_id=ime.item_id) join dimension d on (ime.attr_id=d.attr_id and ime.value_id=d.value_id) where dim_id=? and user_id=? order by score desc";
if (max > 0)
sql = sql + " limit "+max;
Query query = getPM().newQuery( "javax.jdo.query.SQL", sql);
Collection<Object[]> results = (Collection<Object[]>) query.execute(dimension,userId);
Map<Long,Double> map = new HashMap<>();
for(Object[] res : results)
{
Long item = (Long) res[0];
Double score = (Double) res[1];
map.put(item, score);
}
query.closeAll();
return map;
}
}