carmen.demo.LocationResolverDemo.java Source code

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Here is the source code for carmen.demo.LocationResolverDemo.java

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// Copyright 2012-2013 Mark Dredze. All rights reserved.
// This software is released under the 2-clause BSD license.
// Mark Dredze, mdredze@cs.jhu.edu
package carmen.demo;

import java.io.BufferedWriter;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Writer;
import java.text.ParseException;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Scanner;

import org.apache.commons.cli.Option;
import org.apache.log4j.Logger;

import carmen.LocationResolver;
import carmen.types.Location;
import carmen.utils.CommandLineUtilities;
import carmen.utils.Utils;

import com.fasterxml.jackson.databind.ObjectMapper;

/**
 * A simple demo that creates a location resolver and resolves tweets in an input file.
 * @author Mark Dredze mdredze@cs.jhu.edu
 *
 */
public class LocationResolverDemo {
    protected static Logger logger = Logger.getLogger(LocationResolverDemo.class);
    protected static List<Option> options = new LinkedList<Option>();

    public static void main(String[] args)
            throws ParseException, FileNotFoundException, IOException, ClassNotFoundException {
        // Parse the command line.
        String[] manditory_args = { "input_file" };
        createCommandLineOptions();
        CommandLineUtilities.initCommandLineParameters(args, LocationResolverDemo.options, manditory_args);

        // Get options
        String inputFile = CommandLineUtilities.getOptionValue("input_file");
        String outputFile = null;
        if (CommandLineUtilities.hasArg("output_file")) {
            outputFile = CommandLineUtilities.getOptionValue("output_file");
        }

        logger.info("Creating LocationResolver.");
        LocationResolver resolver = LocationResolver.getLocationResolver();

        Scanner scanner = Utils.createScanner(inputFile);

        Writer writer = null;
        if (outputFile != null) {
            writer = Utils.createWriter(outputFile);
            logger.info("Saving geolocated tweets to: " + outputFile);
        }
        ObjectMapper mapper = new ObjectMapper();
        int numResolved = 0;
        int total = 0;
        while (scanner.hasNextLine()) {
            String line = scanner.nextLine();
            @SuppressWarnings("unchecked")
            HashMap<String, Object> tweet = (HashMap<String, Object>) mapper.readValue(line, Map.class);

            total++;
            Location location = resolver.resolveLocationFromTweet(tweet);

            if (location != null) {
                logger.debug("Found location: " + location.toString());
                numResolved++;
            }
            if (writer != null) {
                if (location != null) {
                    tweet.put("location", Location.createJsonFromLocation(location));
                }
                mapper.writeValue(writer, tweet);
                writer.write("\n");
            }

        }
        scanner.close();
        if (writer != null)
            writer.close();

        logger.info("Resolved locations for " + numResolved + " of " + total + " tweets.");
    }

    private static void createCommandLineOptions() {
        Utils.registerOption(options, "input_file", "String", true,
                "A file containing the tweets to locate with geolocation field.");
        Utils.registerOption(options, "output_file", "String", true, "A file to write geolocated tweets.");
    }
}