MongoDBCollectionConversion.java

package com.zynick.mongo;

import java.net.UnknownHostException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;

import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.MongoClient;

import java.text.ParseException;

/**
 * Play around with MongoDB
 * @author zynick
 */
public class MongoDBCollectionConversion {

    static final SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-ddHHmm");
    
    public static void main(String[] args) throws UnknownHostException, ParseException {

        DBCollection spaceCollection = getCollection("tide", "space");
        DBCollection spacesCollection = getCollection("tide", "spaces");
        
        DBCursor cur = spaceCollection.find();
        while (cur.hasNext()) {
            // get data from space
            DBObject obj = cur.next();

            // get and format date
            String dateStr =  (String) obj.get("date");
            Integer hourInt = (Integer) obj.get("hour");
            String hourStr = (hourInt < 10) ? "0" + hourInt : String.valueOf(hourInt);
            Integer bucketInt = (Integer) obj.get("bucket");
            int minute = bucketInt * 5;
            String minuteStr = (minute < 10) ? "0" + minute : String.valueOf(minute);
            Date date = format.parse(dateStr + hourStr + minuteStr);
            
            @SuppressWarnings("rawtypes")
            List devices = (List) obj.get("devices");
            
            // insert data into spaces
            spacesCollection.insert(new BasicDBObject("_id", date)
                            .append("devices", devices)
                            .append("origin", "sprezzaturacoffee"));
        }
        
        System.out.println("gaodim");
    }

    public static DBCollection getCollection(String database, String collection) throws UnknownHostException {
        MongoClient client = new MongoClient();
        DB db = client.getDB(database);
        DBCollection dbCollection = db.getCollection(collection);
        return dbCollection;
    }
    
}