Java tutorial
/* * Copyright 2012 Nodeable Inc * * Licensed 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 com.streamreduce.storm.bolts; import java.util.ArrayList; import java.util.List; import java.util.Map; import backtype.storm.task.OutputCollector; import backtype.storm.task.TopologyContext; import backtype.storm.topology.OutputFieldsDeclarer; import backtype.storm.topology.base.BaseRichBolt; import backtype.storm.tuple.Fields; import backtype.storm.tuple.Tuple; import backtype.storm.tuple.Values; import com.mongodb.BasicDBObject; import com.streamreduce.ConnectionTypeConstants; import com.streamreduce.storm.MongoClient; import org.apache.log4j.Logger; /** * Extension of {@link backtype.storm.topology.base.BaseRichBolt} that will * query Nodeable's datastore for the inventory items associated with the * {@link #execute(backtype.storm.tuple.Tuple)}. */ public class InternalConnectionInventoryBolt extends BaseRichBolt { private static final long serialVersionUID = -5069430729552819142L; private static Logger logger = Logger.getLogger(InternalConnectionInventoryBolt.class); private static final MongoClient mongoClient = new MongoClient(MongoClient.BUSINESSDB_CONFIG_ID); private OutputCollector outputCollector; /** * {@inheritDoc} */ @Override public void prepare(Map map, TopologyContext topologyContext, OutputCollector outputCollector) { this.outputCollector = outputCollector; } /** * {@inheritDoc} */ @Override public void execute(Tuple tuple) { try { BasicDBObject connection = (BasicDBObject) tuple.getValue(0); String id = connection.getString("_id"); String type = connection.getString("type"); List<BasicDBObject> inventoryItems = new ArrayList<>(); if (type.equals(ConnectionTypeConstants.FEED_TYPE)) { // Do nothing, just here for posterity } else if (type.equals(ConnectionTypeConstants.PROJECT_HOSTING_TYPE)) { inventoryItems = mongoClient.getProjectHostingInventoryItems(id); } else if (type.equals(ConnectionTypeConstants.CLOUD_TYPE)) { inventoryItems = mongoClient.getCloudInventoryItems(id); } else { // TODO: We need to figure out how we want to handle this logger.warn(type + " is an unsupported connection type."); } for (BasicDBObject inventoryItem : inventoryItems) { outputCollector.emit(new Values("internal", connection, inventoryItem)); } } catch (Exception e) { logger.error("Unknown exception type in InternalConnectionInventoryBolt " + e.getMessage()); } } /** * {@inheritDoc} */ @Override public void declareOutputFields(OutputFieldsDeclarer outputFieldsDeclarer) { outputFieldsDeclarer.declare(new Fields("type", "connection", "inventoryItem")); } }