nl.utwente.bigdata.bolts.TweetJsonToTextBolt.java Source code

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Here is the source code for nl.utwente.bigdata.bolts.TweetJsonToTextBolt.java

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/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 nl.utwente.bigdata.bolts;

import java.util.Map;

import org.json.simple.parser.JSONParser;

import twitter4j.Status;
import twitter4j.TwitterObjectFactory;
import backtype.storm.task.TopologyContext;
import backtype.storm.topology.BasicOutputCollector;
import backtype.storm.topology.OutputFieldsDeclarer;
import backtype.storm.topology.base.BaseBasicBolt;
import backtype.storm.tuple.Fields;
import backtype.storm.tuple.Tuple;
import backtype.storm.tuple.Values;

public class TweetJsonToTextBolt extends BaseBasicBolt {
    private transient JSONParser parser;

    @Override
    public void prepare(Map stormConf, TopologyContext context) {
        parser = new JSONParser();
    }

    @Override
    public void execute(Tuple tuple, BasicOutputCollector collector) {
        try {
            Status tweet = TwitterObjectFactory.createStatus(tuple.getString(0));
            //        String text = (String) tweet.get("text");
            //        String lang = (String) tweet.get("lang");
            //        String createdAt = (String) tweet.get("created_at");

            if (!tweet.isRetweet()) {
                collector.emit(new Values(tweet));
            }
        } catch (ClassCastException e) {
            System.out.println("ClassCass");
            e.printStackTrace();
            return; // do nothing (we might log this)
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    public void declareOutputFields(OutputFieldsDeclarer declarer) {
        declarer.declare(new Fields("tweet"));
    }

}