| /** |
| * 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.starter.streams; |
| |
| import java.util.Arrays; |
| import org.apache.storm.Config; |
| import org.apache.storm.StormSubmitter; |
| import org.apache.storm.starter.spout.RandomSentenceSpout; |
| import org.apache.storm.streams.Pair; |
| import org.apache.storm.streams.StreamBuilder; |
| import org.apache.storm.streams.operations.mappers.ValueMapper; |
| import org.apache.storm.streams.windowing.TumblingWindows; |
| import org.apache.storm.topology.base.BaseWindowedBolt.Duration; |
| |
| /** |
| * A windowed word count example. |
| */ |
| public class WindowedWordCount { |
| public static void main(String[] args) throws Exception { |
| StreamBuilder builder = new StreamBuilder(); |
| // A stream of random sentences |
| builder.newStream(new RandomSentenceSpout(), new ValueMapper<String>(0), 2) |
| /* |
| * a two seconds tumbling window |
| */ |
| .window(TumblingWindows.of(Duration.seconds(2))) |
| /* |
| * split the sentences to words |
| */ |
| .flatMap(s -> Arrays.asList(s.split(" "))) |
| /* |
| * create a stream of (word, 1) pairs |
| */ |
| .mapToPair(w -> Pair.of(w, 1)) |
| /* |
| * compute the word counts in the last two second window |
| */ |
| .countByKey() |
| /* |
| * emit the count for the words that occurred |
| * at-least five times in the last two seconds |
| */ |
| .filter(x -> x.getSecond() >= 5) |
| /* |
| * print the results to stdout |
| */ |
| .print(); |
| |
| Config config = new Config(); |
| String topoName = "test"; |
| if (args.length > 0) { |
| topoName = args[0]; |
| } |
| config.setNumWorkers(1); |
| StormSubmitter.submitTopologyWithProgressBar(topoName, config, builder.build()); |
| } |
| } |