Java tutorial
/* * Licensed to Booz Allen Hamilton under one or more contributor * license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright * ownership. Booz Allen Hamilton 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 com.boozallen.cognition.ingest.accumulo.storm; import backtype.storm.task.TopologyContext; import com.boozallen.cognition.ingest.accumulo.utils.AccumuloConnectionConfig; import com.boozallen.cognition.ingest.accumulo.utils.AccumuloConnectionUtils; import com.boozallen.cognition.ingest.storm.PrepareFailedException; import com.boozallen.cognition.ingest.storm.bolt.AbstractProcessingBolt; import org.apache.accumulo.core.client.*; import org.apache.accumulo.core.client.security.tokens.PasswordToken; import org.apache.commons.configuration.Configuration; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.util.Map; import java.util.concurrent.TimeUnit; /** * Base bolt for writing to accumulo. Manages accumulo configuration and connection. */ public abstract class AccumuloBaseBolt extends AbstractProcessingBolt { private final Logger logger = LoggerFactory.getLogger(this.getClass()); protected AccumuloConnectionConfig accumuloConnConfig; protected BatchWriterConfig config; protected Connector conn; @Override public final void configure(Configuration conf) { accumuloConnConfig = AccumuloConnectionUtils.extractConnectionConfiguration(conf); configureAccumuloBolt(conf); } abstract void configureAccumuloBolt(Configuration conf); @Override public final void prepare(Map stormConf, TopologyContext context) { Instance inst = new ZooKeeperInstance(accumuloConnConfig.getInstance(), accumuloConnConfig.getZooServers()); try { conn = inst.getConnector(accumuloConnConfig.getUser(), new PasswordToken(accumuloConnConfig.getKey())); config = new BatchWriterConfig(); config.setMaxMemory(accumuloConnConfig.getMaxMem()); config.setMaxLatency(accumuloConnConfig.getMaxLatency(), TimeUnit.MILLISECONDS); config.setMaxWriteThreads(accumuloConnConfig.getMaxWriteThreads()); } catch (AccumuloException e) { logger.error("Failed to get Connection", e); throw new PrepareFailedException("Failed to get Connection", e); } catch (AccumuloSecurityException e) { logger.error("Failed to authenticate", e); throw new PrepareFailedException("Failed to authenticate", e); } prepareAccumuloBolt(stormConf, context); } abstract void prepareAccumuloBolt(Map stormConf, TopologyContext context); }