in.dream_lab.eventgen.factory.LoadCsvToMemory.java Source code

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Here is the source code for in.dream_lab.eventgen.factory.LoadCsvToMemory.java

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/**
 * Copyright 2015 DREAM:Lab, Indian Institute of Science, Bangalore
 *
 * 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 in.dream_lab.eventgen.factory;

import com.opencsv.CSVReader;
import org.joda.time.DateTime;
import org.joda.time.format.ISODateTimeFormat;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.FileReader;
import java.io.IOException;
import java.text.ParseException;
import java.util.ArrayList;
import java.util.HashMap;

/*
 * Splits the CSV file in round-robin manner and stores it to individual files
 * based on the number of threads
 */
public class LoadCsvToMemory {
    public static Logger LOG = LoggerFactory.getLogger(LoadCsvToMemory.class);

    public static ArrayList<RowClass> loadListFromCSV(String csvFileName) throws IOException {
        CSVReader reader = new CSVReader(new FileReader(csvFileName));
        String[] nextLine;
        int ctr = 0;
        String[] headers = reader.readNext(); //use .intern() later
        ArrayList<RowClass> arr = new ArrayList<RowClass>();

        while ((nextLine = reader.readNext()) != null) {
            // nextLine[] is an array of values from the line
            //System.out.println(nextLine[0] +  "  "  + nextLine[1] + "   " + nextLine[2] + "  " + nextLine[3]  + "  etc...");

            HashMap<String, String> map = new HashMap<String, String>();
            for (int i = 0; i < nextLine.length; i++) {
                map.put(headers[i], nextLine[i]);
            }
            DateTime date = ISODateTimeFormat.dateTimeParser().parseDateTime(nextLine[0]);
            long ts = date.getMillis();
            RowClass rowClass = new RowClass(ts, map);
            arr.add(rowClass);

            ctr++;
        }

        return arr;
    }

    /**
     * @param args
     * @throws ParseException
     * @throws IOException
     */
    public static void main(String[] args) throws ParseException, IOException {
        // TODO Auto-generated method stub
        String csvFileName = "/var/tmp/SyS/out/output" + 3 + ".csv";
        ArrayList<RowClass> arr = loadListFromCSV(csvFileName);
        System.out.println(arr.size());
        LOG.info("jkl");
    }
}