io.seldon.similarity.item.JdoItemSimilarityPeer.java Source code

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Here is the source code for io.seldon.similarity.item.JdoItemSimilarityPeer.java

Source

/*
 * 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;
    }

}