Java tutorial
/* * 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.clustering.recommender; import io.seldon.clustering.recommender.jdo.JdoCountRecommenderUtils; import java.util.ArrayList; import java.util.Collections; import java.util.List; import java.util.Map; import java.util.Set; import org.apache.log4j.Logger; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Component; /** * @author firemanphil * Date: 10/12/14 * Time: 17:00 */ @Component public class ItemCategoryClusterCountsRecommender extends BaseItemCategoryRecommender implements ItemRecommendationAlgorithm { private static final String name = ItemCategoryClusterCountsRecommender.class.getSimpleName(); private static final String DECAY_RATE_OPTION_NAME = "io.seldon.algorithm.clusters.decayratesecs"; private static Logger logger = Logger.getLogger(ItemCategoryClusterCountsRecommender.class.getName()); @Autowired JdoCountRecommenderUtils cUtils; @Override public ItemRecommendationResultSet recommend(String client, Long user, int dimensionId, int maxRecsCount, RecommendationContext ctxt, List<Long> recentItemInteractions) { if (ctxt.getCurrentItem() != null) { Set<Long> exclusions = Collections.emptySet(); if (ctxt.getMode() == RecommendationContext.MODE.EXCLUSION) { exclusions = ctxt.getContextItems(); } Integer dimId = getDimensionForAttrName(ctxt.getCurrentItem(), client, ctxt); if (dimId != null) { CountRecommender r = cUtils.getCountRecommender(client); if (r != null) { Double decayRate = ctxt.getOptsHolder().getDoubleOption(DECAY_RATE_OPTION_NAME); long t1 = System.currentTimeMillis(); Map<Long, Double> recommendations = r.recommendGlobal(dimensionId, maxRecsCount, exclusions, decayRate, dimId); long t2 = System.currentTimeMillis(); logger.debug("Recommendation via cluster counts for dimension " + dimId + " for item " + ctxt.getCurrentItem() + " for user " + user + " took " + (t2 - t1)); List<ItemRecommendationResultSet.ItemRecommendationResult> results = new ArrayList<>(); for (Map.Entry<Long, Double> entry : recommendations.entrySet()) { results.add(new ItemRecommendationResultSet.ItemRecommendationResult(entry.getKey(), entry.getValue().floatValue())); } return new ItemRecommendationResultSet(results, name); } else logger.warn("Can't get count recommender for " + client); } else logger.info("Can't get dim for item " + ctxt.getCurrentItem() + " so can't run cluster counts for dimension algorithm "); } else logger.info("Can't cluster count for category for user " + user + " client user id " + ctxt.getCurrentItem() + " as no current item passed in"); return new ItemRecommendationResultSet(Collections.EMPTY_LIST, name); } @Override public String name() { return name; } }