rtb.PopularTweetCollector.java Source code

Introduction

Here is the source code for rtb.PopularTweetCollector.java

Source

/*
 * Copyright 2014 Kohei Yamamoto
 *
 * 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 rtb;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Date;
import java.util.List;
import java.util.stream.Collectors;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import twitter4j.Paging;
import twitter4j.Status;
import twitter4j.Twitter;
import twitter4j.TwitterException;
import twitter4j.TwitterFactory;

import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.ObjectMapper;

public class PopularTweetCollector {
    private Twitter twitter;
    private Logger logger;

    public PopularTweetCollector() {
        twitter = TwitterFactory.getSingleton();
        logger = LoggerFactory.getLogger(PopularTweetCollector.class);
    }

    /**
     * Get the date of latest status of the user.
     * @param userScreenName the screen name of user
     * @return the date of latest status of user who is specified in parameter
     * @throws TwitterException
     */
    public Date getLatestTweetDate(String userScreenName) throws TwitterException {
        if (userScreenName == null)
            throw new NullPointerException();
        return twitter.getUserTimeline(userScreenName, new Paging(1, 1)).get(0).getCreatedAt();
    }

    /**
     * Write out the list of popular tweets in JSON form. Each tweet in the list has the number of favs which is greater than favThreshold.
     * @param userScreenName the screen name of user
     * @param favThreshold the threshold of the number of favs
     * @param fileName JSON file name
     * @return the list of statuses
     * @throws TwitterException
     * @throws JsonParseException
     * @throws IOException
     */
    public List<Status> collectPopularTweets(String userScreenName, final int favThreshold, String fileName)
            throws JsonParseException, IOException {
        if (userScreenName == null || fileName == null)
            throw new NullPointerException();
        if (favThreshold < 0)
            throw new IllegalArgumentException();

        List<Status> tweets = new ArrayList<>();
        try {
            for (int page = 1;; ++page) {
                List<Status> statuses = twitter.getUserTimeline(userScreenName, new Paging(page, 200));

                if (statuses.size() == 0) {
                    logger.info("Collect tweets from {} [fav >= {}].", userScreenName, favThreshold);
                    return tweets;
                }
                tweets.addAll(statuses.stream().filter(s -> s.getFavoriteCount() >= favThreshold)
                        .collect(Collectors.toList()));
            }
        } catch (TwitterException e) {
            logger.info("Collect failed.", e);
            return Collections.emptyList();
        }
    }

    /**
     * Write out the list of tweets to JSON form.
     * @param statuses the list of statuses
     * @param fileName JSON file name
     * @throws JsonParseException
     * @throws IOException
     */
    public void writeAsJson(List<? extends Status> statuses, String fileName)
            throws JsonParseException, IOException {
        if (statuses == null || fileName == null)
            throw new NullPointerException();
        if (statuses.isEmpty())
            return;

        // Convert Status to TweetPojo
        List<Tweet> pojos = new ArrayList<>(statuses.size());
        for (Status s : statuses) {
            // Get tweet text
            String text = s.getText().replaceAll("[\n\t]", " ");

            // Get formatted date text
            DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm");
            String date = formatter.format(s.getCreatedAt());

            String screenName = s.getUser().getScreenName();

            pojos.add(new Tweet(screenName, text, date, s.getFavoriteCount(), getTweetURL(s)));
        }

        // Write out TweetPojo as JSON
        FileWriter writer = new FileWriter(new File(fileName));
        ObjectMapper mapper = new ObjectMapper();
        mapper.writeValue(writer, pojos);
    }

    private String getTweetURL(Status status) {
        return "https://twitter.com/" + status.getUser().getScreenName() + "/status/" + status.getId();
    }
}