implementations.mongoDB.java Source code

Introduction

Here is the source code for implementations.mongoDB.java

Source

package implementations;
/**
 * Copyright 2011 Thibault Dory
 * Licensed under the GPL Version 3 license
 */

import java.net.UnknownHostException;
import java.util.ArrayList;

import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.MapReduceOutput;
import com.mongodb.Mongo;
import com.mongodb.MongoException;
import com.mongodb.util.JSON;

import core.BenchDB;

/**
 * 
 * @author Thibault Dory
 *
 */

public class mongoDB extends BenchDB {
    DB db;
    Mongo mdb;
    DBCollection dbCol;

    @Override
    public int connectNode(String nodeAddress) {
        int ret;
        try {
            mdb = new Mongo(nodeAddress);
            //mdb.slaveOk();
            db = mdb.getDB("test");
            dbCol = db.getCollection("test");
            DBCursor cur = dbCol.find();
            ret = 1;
        } catch (UnknownHostException e) {
            ret = -1;
            e.printStackTrace();
        } catch (MongoException e) {
            ret = 1;
            e.printStackTrace();
        }
        return ret;
    }

    @Override
    public String readDB(String ID) {
        String ret;
        try {
            db.requestStart();
            BasicDBObject query = new BasicDBObject();
            query.put("_id", ID);
            DBCursor cur = dbCol.find(query);
            ret = "";
            while (cur.hasNext()) {
                DBObject temp = (DBObject) JSON.parse(cur.next().toString());
                ret = (String) temp.get("artValue");

            }
            db.requestDone();
        } catch (Exception e) {
            e.printStackTrace();
            ret = null;
        }
        return ret;
    }

    public int writeDB(String ID, String newValue) {
        int ret;
        try {
            db.requestStart();
            BasicDBObject doc = new BasicDBObject();
            doc.put("_id", ID);
            doc.put("artValue", newValue);
            dbCol.insert(doc);
            db.requestDone();
            ret = 1;
        } catch (Exception e) {
            e.printStackTrace();
            ret = -1;
        }
        return ret;
    }

    @Override
    public int updateDB(String ID, String newValue) {
        int ret;
        try {
            db.requestStart();
            BasicDBObject query = new BasicDBObject();
            query.put("_id", ID);
            DBCursor cur = dbCol.find(query);
            cur.next();
            BasicDBObject doc = new BasicDBObject();
            doc.put("_id", ID);
            doc.put("artValue", newValue);
            dbCol.update(cur.curr(), doc);
            db.requestDone();
            ret = 1;
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("ID = " + ID + " ===============================");
            ret = -1;
        }
        return ret;
    }

    public void searchDB(String keyword) {
        ArrayList<String> res = new ArrayList<String>();
        String map_index = "function() {" + "var words = this.artValue.split(' ');" + "var keyword = \"" + keyword
                + "\";" + "for ( var i=0; i<words.length; i++ ) {"
                + "if(words[i].toLowerCase()  == keyword.toLowerCase() ){" + "emit(words[i], { docs: [this._id] });"
                + "}}}";

        String reduce_index = "function(key, values) {" + "var docs = [];"
                + "values.forEach ( function(val) { docs = docs.concat(val.docs); });" + "return { docs: docs };}";

        String map_relevance = "function() {" + "for ( var i=0; i< this.value.docs.length; i++ ) {"
                + "emit(this.value.docs[i], { count: 1 });}}";

        String reduce_relevance = "function(key, values) {" + "var sum = 0;"
                + "values.forEach ( function(val) { sum += val.count; });" + "return { count: sum };}";

        //First MapReduce phase
        MapReduceOutput tempRes = dbCol.mapReduce(map_index, reduce_index, "tempRes1", null);
        DBCollection outCol = tempRes.getOutputCollection();
        //Second MapReduce phase
        MapReduceOutput tempRes2 = outCol.mapReduce(map_relevance, reduce_relevance, "tempRes2", null);
        //      DBCollection outCol2 = tempRes2.getOutputCollection();
        //      DBCursor cur = outCol2.find();
        //      while(cur.hasNext()){
        //         res.add(cur.next().toString());
        //      }
        //      System.out.println(res);
    }

    @Override
    public void close() {
        mdb.close();
    }

}