| /** |
| * 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 storm.starter; |
| |
| import backtype.storm.Config; |
| import backtype.storm.LocalCluster; |
| import backtype.storm.LocalDRPC; |
| import backtype.storm.StormSubmitter; |
| import backtype.storm.drpc.LinearDRPCTopologyBuilder; |
| 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; |
| |
| /** |
| * This topology is a basic example of doing distributed RPC on top of Storm. It implements a function that appends a |
| * "!" to any string you send the DRPC function. |
| * <p/> |
| * See https://github.com/nathanmarz/storm/wiki/Distributed-RPC for more information on doing distributed RPC on top of |
| * Storm. |
| */ |
| public class BasicDRPCTopology { |
| public static class ExclaimBolt extends BaseBasicBolt { |
| @Override |
| public void execute(Tuple tuple, BasicOutputCollector collector) { |
| String input = tuple.getString(1); |
| collector.emit(new Values(tuple.getValue(0), input + "!")); |
| } |
| |
| @Override |
| public void declareOutputFields(OutputFieldsDeclarer declarer) { |
| declarer.declare(new Fields("id", "result")); |
| } |
| |
| } |
| |
| public static void main(String[] args) throws Exception { |
| LinearDRPCTopologyBuilder builder = new LinearDRPCTopologyBuilder("exclamation"); |
| builder.addBolt(new ExclaimBolt(), 3); |
| |
| Config conf = new Config(); |
| |
| if (args == null || args.length == 0) { |
| LocalDRPC drpc = new LocalDRPC(); |
| LocalCluster cluster = new LocalCluster(); |
| |
| cluster.submitTopology("drpc-demo", conf, builder.createLocalTopology(drpc)); |
| |
| for (String word : new String[]{ "hello", "goodbye" }) { |
| System.out.println("Result for \"" + word + "\": " + drpc.execute("exclamation", word)); |
| } |
| |
| cluster.shutdown(); |
| drpc.shutdown(); |
| } |
| else { |
| conf.setNumWorkers(3); |
| StormSubmitter.submitTopologyWithProgressBar(args[0], conf, builder.createRemoteTopology()); |
| } |
| } |
| } |