001/**
002 * Copyright (c) 2011, The University of Southampton and the individual contributors.
003 * All rights reserved.
004 *
005 * Redistribution and use in source and binary forms, with or without modification,
006 * are permitted provided that the following conditions are met:
007 *
008 *   *  Redistributions of source code must retain the above copyright notice,
009 *      this list of conditions and the following disclaimer.
010 *
011 *   *  Redistributions in binary form must reproduce the above copyright notice,
012 *      this list of conditions and the following disclaimer in the documentation
013 *      and/or other materials provided with the distribution.
014 *
015 *   *  Neither the name of the University of Southampton nor the names of its
016 *      contributors may be used to endorse or promote products derived from this
017 *      software without specific prior written permission.
018 *
019 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
020 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
021 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
022 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
023 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
024 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
025 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
026 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
027 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
028 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
029 */
030package org.openimaj.stream.provider.twitter;
031
032import java.util.List;
033
034import org.openimaj.util.api.auth.common.TwitterAPIToken;
035import org.openimaj.util.concurrent.BlockingDroppingQueue;
036import org.openimaj.util.data.Context;
037
038import twitter4j.Query;
039import twitter4j.Status;
040
041/**
042 * Extends the {@link TwitterSearchDataset} to support multiple queries. All
043 * attempts are made to access the Twitter API in a fair way. Each query is
044 * handled in turn and backoffs, new results etc. are stored per query.
045 * <p>
046 * A round robin approach is used to fill the underlying
047 * {@link BlockingDroppingQueue}. Each query is given a chance to fill the
048 * queue, then all appropriate wait times are respected and the next query is
049 * given a chance.
050 * <p>
051 * Further this round robin dataset passes {@link QueryHoldingStatus} instances
052 * due to the variable queue.
053 * 
054 * @author Sina Samangooei (ss@ecs.soton.ac.uk)
055 */
056public class ContextRoundRobinTwitterSearchAPIDataset extends AbstractTwitterSearchDataset<Context> {
057
058        private List<Query> queries;
059        private int currentQuery;
060
061        /**
062         * @param queries
063         * @param token
064         * @param buffer
065         */
066        public ContextRoundRobinTwitterSearchAPIDataset(List<Query> queries, TwitterAPIToken token,
067                        BlockingDroppingQueue<Context> buffer)
068        {
069                super(token, buffer, queries.get(0));
070
071                this.queries = queries;
072                this.currentQuery = 0;
073        }
074
075        @Override
076        public Query getQuery() {
077                final Query retQuery = this.queries.get(this.currentQuery);
078                nextQuery();
079                return retQuery;
080        }
081
082        private void nextQuery() {
083                this.currentQuery++;
084                if (this.currentQuery >= this.queries.size())
085                        this.currentQuery = 0;
086        }
087
088        @Override
089        public void registerStatus(Query query, Status status, String json) throws InterruptedException {
090                final Context c = new Context();
091                c.put("query", query);
092                c.put("status", status);
093                c.put("status_json", json);
094                register(c);
095        }
096}