MongoModel

2019独角兽企业重金招聘Python工程师标准>>>

package com.lovego.cloud.perception.mahout;
import java.net.UnknownHostException;
import java.util.Collection;
import java.util.Map;

import org.apache.mahout.cf.taste.impl.common.FastByIDMap;
import org.apache.mahout.cf.taste.impl.model.GenericDataModel;
import org.apache.mahout.cf.taste.impl.model.GenericPreference;
import org.apache.mahout.cf.taste.model.DataModel;
import org.apache.mahout.cf.taste.model.Preference;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.collect.Lists;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.Mongo;

public final class MongoModel {
    private static final Logger log = LoggerFactory.getLogger(MongoModel.class);
    private static final String DEFAULT_USER_FIELD = "user";
    private static final String DEFAULT_ITEM_FIELD = "item";
    private static final String DEFAULT_RATING_FIELD = "score";
    private static final String DEFAULT_IPADDR = "127.0.0.1";
    private static final int DEFAULT_PORT = 27017;
    private static final String DEFAULT_DBNMAE = "recommend";
    private static final String DEFAULT_TABLE_NMAE = "preference";
    private String m_strHost;
    private int m_iPort;
    private String m_strDBName;
    private String m_strTableName;
    private String m_strUserFieldName;
    private String m_strItemFileldName;
    private String m_strScoreFieldName;
    private DataModel m_oDataModel;

    public MongoModel(String strHost, int port, String strDBName, String strTableName, String strUserFiledName,
            String strItemFiledName, String strScoreFiledName) throws UnknownHostException {
        m_strHost = strHost != "" ? strHost : DEFAULT_IPADDR;
        m_iPort = port > 0 ? port : DEFAULT_PORT;
        m_strDBName = strDBName != "" ? strDBName : DEFAULT_DBNMAE;
        m_strTableName = strTableName != "" ? strTableName : DEFAULT_TABLE_NMAE;
        m_strUserFieldName = strUserFiledName != "" ? strUserFiledName : DEFAULT_USER_FIELD;
        m_strItemFileldName = strItemFiledName != "" ? strItemFiledName : DEFAULT_ITEM_FIELD;
        m_strScoreFieldName = strScoreFiledName != "" ? strScoreFiledName : DEFAULT_RATING_FIELD;
        BuildModel() ; 
    }

    private void BuildModel() throws UnknownHostException {
        Mongo mongoDDBB = new Mongo(m_strHost, m_iPort);
        DB db = mongoDDBB.getDB(m_strDBName);
        DBCollection collection = db.getCollection(m_strTableName);

        DBCursor cursor = collection.find();
        FastByIDMap<Collection<Preference>> userIDPrefMap = new FastByIDMap<Collection<Preference>>();
        while (cursor.hasNext()) {
            Map<String, Object> a = (Map<String, Object>) cursor.next().toMap();
            long uid = Object2Long(a.get( m_strUserFieldName ));
            long item = Object2Long(a.get(m_strItemFileldName ));
            float ratingValue = getPreference(a.get(m_strScoreFieldName));
           // log.info(String.valueOf(uid) + "\t\t" + String.valueOf(item) + "\t\t" + String.valueOf(ratingValue));
            //System.out.println(String.valueOf(uid) + "\t\t" + String.valueOf(item) + "\t\t" + String.valueOf(ratingValue));

            Collection<Preference> userPrefs = userIDPrefMap.get(uid);
            if (userPrefs == null) {
                userPrefs = Lists.newArrayListWithCapacity(2);
                userIDPrefMap.put(uid, userPrefs);
            }
            userPrefs.add(new GenericPreference(uid, item, ratingValue));
        }
        m_oDataModel = new GenericDataModel(GenericDataModel.toDataMap(userIDPrefMap, true));
    }

    public DataModel DataModel() {
        return m_oDataModel;
    }

    private static long Object2Long(Object o) {
        if (o != null) {
            return Double.valueOf(o.toString()).longValue();
        }
        return 0;
    }

    private static float getPreference(Object value) {
        if (value != null) {
            if (value.getClass().getName().contains("String")) {
                return Float.parseFloat(value.toString());
            } else {
                return Double.valueOf(value.toString()).floatValue();
            }
        } else {
            return 0.5f;
        }
    }

}

package com.lovego.cloud.perception.mahout;

import java.util.List;

import org.apache.mahout.cf.taste.impl.recommender.GenericItemBasedRecommender;
import org.apache.mahout.cf.taste.impl.similarity.PearsonCorrelationSimilarity;
import org.apache.mahout.cf.taste.model.DataModel;
import org.apache.mahout.cf.taste.recommender.RecommendedItem;
import org.apache.mahout.cf.taste.similarity.ItemSimilarity;

/**
 * 基于物品的协同过滤
 * @author Administrator
 *
 */
public class ItemCFMongo {

	final static int RECOMMENDER_NUM = 3; //推荐物品数目
	
	public static void main(String[] args) throws Exception {
		
		long start = System.currentTimeMillis();
		/*MongoDBDataModel model = new MongoDBDataModel("127.0.0.1", 27017, "test",
				"user_behavior", false, false, null,"userId","spuId","actionType","user_behavior");*/
		
		
		MongoModel _d = new MongoModel("127.0.0.1", 27017 , "test" ,"user_behavior" , "userId","spuId","actionType") ; 
		
		DataModel model = _d.DataModel() ; 
		
		
		 long end = System.currentTimeMillis();
			System.out.println("模型加載耗时>>>>>>>>>>>>>>>>>>>>>>>>>>"+ (end -start));
		
		//使用皮尔松算法 计算内容之间的相似度
		ItemSimilarity itemSimilarity = new PearsonCorrelationSimilarity(model); 
		
		//构造推荐引擎 基于物品的推荐
		GenericItemBasedRecommender r = new GenericItemBasedRecommender(model, itemSimilarity);
		
		//迭代获取用户的id
			//获得推荐结果，给userID推荐howMany个Item
			List<RecommendedItem> list = r.mostSimilarItems(18438, RECOMMENDER_NUM);
			for(RecommendedItem items : list){
				System.out.printf("(%s,%f)",items.getItemID(),items.getValue());
			}
			System.out.println();
		
	}
	
}

 

转载于:https://my.oschina.net/xiaominmin/blog/1835861