com.congiu.load.csv.Main.java Source code

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Here is the source code for com.congiu.load.csv.Main.java

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/*
 * Copyright (C) 2015 Roberto Congiu <rcongiu@yahoo.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
package com.congiu.load.csv;

import java.io.PrintWriter;
import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.CommandLineParser;
import org.apache.commons.cli.DefaultParser;
import org.apache.commons.cli.HelpFormatter;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;

import org.apache.hadoop.conf.Configuration;

/**
 *
 * @author Roberto Congiu <rcongiu@yahoo.com>
 */
public class Main {
    public static String[] OPT_HELP = { "h", "help" };
    public static String[] OPT_DEST = { "d", "destination" };

    public static void main(String[] args) {
        Options opts = buildCommandLineOptions();

        Configuration conf = new Configuration();

        try {
            CommandLine cmd = processArguments(opts, args);

            if (cmd.hasOption(OPT_HELP[0])) {
                printUsage(opts, new PrintWriter(System.out));
                System.exit(0);
            }

            // all unprocessed arguments are files.
            // let's first check if they all exist
            for (String s : cmd.getArgs()) {
                if (!FSUtils.fileExists(conf, s)) {
                    throw new Exception("File " + s + " does not exist.");
                }
            }

            CSVConverter converter = getCSVConverter(cmd);

            for (String s : cmd.getArgs()) {

            }

        } catch (Exception ex) {
            System.err.println("There was a problem parsing your arguments.");
            System.err.println(ex);
            printUsage(opts, new PrintWriter(System.err));
            System.exit(-1);
        }
    }

    static void printUsage(Options options, PrintWriter pw) {
        HelpFormatter formatter = new HelpFormatter();
        formatter.printHelp(pw, 80, "load-csv [options] file [,file...]",
                "loads one or more csv files to HDFS, converting them to " + "a more appropriate format", options,
                2, 2, "");
        pw.flush();

    }

    static CommandLine processArguments(Options opts, String[] args) throws ParseException {
        CommandLineParser parser = new DefaultParser();
        return parser.parse(opts, args);
    }

    static Options buildCommandLineOptions() {
        Options opts = new Options();

        addOption(opts, OPT_HELP, false, "Show help.");
        addOption(opts, OPT_DEST, true, "Destination Directory");

        return opts;
    }

    /*
    Utility method to add options 
    */
    static void addOption(Options opts, String[] opt, boolean param, String text) {
        opts.addOption(opt[0], opt[1], param, text);
    }

    /** 
     * factory method to instantiate the correct converter
     * based on command line options.
     * Parquet, SequenceFile, etc.
     * @param cmd
     * @return 
     */
    private static CSVConverter getCSVConverter(CommandLine cmd) {
        throw new UnsupportedOperationException("Not supported yet.");
    }

}