| /* |
| * 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 org.apache.storm.perf.bolt; |
| |
| import java.util.HashMap; |
| import java.util.Map; |
| import org.apache.storm.task.TopologyContext; |
| import org.apache.storm.topology.BasicOutputCollector; |
| import org.apache.storm.topology.OutputFieldsDeclarer; |
| import org.apache.storm.topology.base.BaseBasicBolt; |
| import org.apache.storm.tuple.Fields; |
| import org.apache.storm.tuple.Tuple; |
| import org.apache.storm.tuple.Values; |
| |
| |
| public class CountBolt extends BaseBasicBolt { |
| public static final String FIELDS_WORD = "word"; |
| public static final String FIELDS_COUNT = "count"; |
| |
| Map<String, Integer> counts = new HashMap<>(); |
| |
| @Override |
| public void prepare(Map<String, Object> topoConf, TopologyContext context) { |
| } |
| |
| @Override |
| public void execute(Tuple tuple, BasicOutputCollector collector) { |
| String word = tuple.getString(0); |
| Integer count = counts.get(word); |
| if (count == null) { |
| count = 0; |
| } |
| count++; |
| counts.put(word, count); |
| collector.emit(new Values(word, count)); |
| } |
| |
| @Override |
| public void declareOutputFields(OutputFieldsDeclarer declarer) { |
| declarer.declare(new Fields(FIELDS_WORD, FIELDS_COUNT)); |
| } |
| } |