io.seldon.recommendation.baseline.jdo.SqlStaticRecommendationsProvider.java Source code

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/*
 * 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.recommendation.baseline.jdo;

import io.seldon.api.Constants;
import io.seldon.db.jdo.ClientPersistable;
import io.seldon.recommendation.baseline.IStaticRecommendationsProvider;

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;

public class SqlStaticRecommendationsProvider extends ClientPersistable implements IStaticRecommendationsProvider {

    public SqlStaticRecommendationsProvider(String clientName) {
        super(clientName);
    }

    @Override
    public Map<Long, Double> getStaticRecommendations(long userId, 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 item_id,score from recommendations where user_id=? 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(userId);
            results = (Collection<Object[]>) query.executeWithArray(args.toArray());
        } else {
            String dimensionsStr = StringUtils.join(dimensions, ",");
            String sql = "select recs.item_id,score from recommendations recs join item_map_enum ime on (recs.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 recs.user_id=? 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(userId);
            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;
    }

}