Java tutorial
/* ============================================================================ * * FILE: DistributedFileSupportService.java * The MIT License (MIT) Copyright (c) 2016 Sutanu Dalui Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * * ============================================================================ */ package com.reactive.hzdfs.core; import java.io.File; import java.io.IOException; import java.io.InterruptedIOException; import java.util.Iterator; import java.util.Map; import java.util.WeakHashMap; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; import java.util.concurrent.ThreadFactory; import java.util.concurrent.TimeUnit; import javax.annotation.PostConstruct; import javax.annotation.PreDestroy; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Value; import org.springframework.stereotype.Service; import com.hazelcast.core.ICountDownLatch; import com.hazelcast.core.Message; import com.reactive.hzdfs.IDistributedFileSupport; import com.reactive.hzdfs.cluster.HazelcastClusterServiceBean; import com.reactive.hzdfs.cluster.IMapConfig; import com.reactive.hzdfs.cluster.MessageChannel; import com.reactive.hzdfs.dto.DFSSCommand; import com.reactive.hzdfs.dto.DFSSResponse; import com.reactive.hzdfs.dto.DFSSTaskConfig; /** * Implementation class for {@linkplain IDistributedFileSupport}. */ @Service public class DistributedFileSupportService implements MessageChannel<DFSSCommand>, IDistributedFileSupport { private static final Logger log = LoggerFactory.getLogger(DistributedFileSupportService.class); @Autowired HazelcastClusterServiceBean hzService; /** * */ public DistributedFileSupportService() { } private String commandTopicId; @Value("${dfss.threadCount:4}") private int nThreads; private IMapConfig recordMapCfg; @PostConstruct private void init() { commandTopicId = hzService.addMessageChannel(this); threads = Executors.newFixedThreadPool(nThreads, new ThreadFactory() { int n = 0; @Override public Thread newThread(Runnable r) { Thread t = new Thread(r, "DFSS-Worker-" + (n++)); return t; } }); recordMapCfg = RecordMapConfig.class.getAnnotation(IMapConfig.class); log.info("[DFSS] File distribution service initialized"); } @PreDestroy private void destroy() { threads.shutdown(); try { threads.awaitTermination(60, TimeUnit.SECONDS); } catch (InterruptedException e) { } hzService.removeMessageChannel(topic(), commandTopicId); removeAllDistributor(); } /* (non-Javadoc) * @see com.reactive.hzdfs.core.IDistributedFileSystem#distribute(java.io.File) */ @Override public Future<DFSSResponse> distribute(File sourceFile, DFSSTaskConfig config) throws IOException { log.info("[DFSS] Initiating distribution for local file " + sourceFile + "; Checking attributes.."); checkFile(sourceFile); DFSSTaskExecutor w = prepareTaskExecutor(sourceFile, config); log.info("[DFSS#" + w.sessionId + "] Coordinator prepared. Submitting task for execution.."); return threads.submit(w); } private ExecutorService threads; /** * * @param sourceFile * @param config * @return * @throws IOException */ private DFSSTaskExecutor prepareTaskExecutor(File sourceFile, DFSSTaskConfig config) throws IOException { DFSSCommand cmd = prepareCluster(sourceFile, config); DFSSTaskExecutor w = new DFSSTaskExecutor(this, sourceFile.getName().toUpperCase(), sourceFile, createChunkCollector(cmd)); w.sessionId = cmd.getSessionId(); w.recordMap = cmd.getRecordMap(); return w; } //private CountDownLatch latch; /** * * @param sourceFile * @throws IOException */ private void checkFile(File sourceFile) throws IOException { if (sourceFile == null) throw new IOException("Source file is null"); if (!sourceFile.exists()) throw new IOException("Source file does not exist"); if (!sourceFile.isFile()) throw new IOException("Not a valid file"); if (!sourceFile.canRead()) throw new IOException("Cannot read source file"); } private static String chunkMapName(File sourceFile) { //TODO: Using replaceAll breaks the code!! return sourceFile.getName()/*.replaceAll("\\.", "_")*/.toUpperCase(); } private ICountDownLatch sessionLatch(DFSSCommand cmd) { return hzService.getClusterLatch("DFSS_" + cmd.getSessionId()); } /** * * @param sourceFile * @param config * @return * @throws IOException */ private DFSSCommand prepareCluster(File sourceFile, DFSSTaskConfig config) throws IOException { DFSSCommand cmd = new DFSSCommand(); cmd.setConfig(config); log.info("[DFSS] New task created with sessionId => " + cmd.getSessionId() + " for file => " + sourceFile); cmd.setCommand(DFSSCommand.CMD_INIT_ASCII_RCVRS); cmd.setChunkMap(chunkMapName(sourceFile)); cmd.setRecordMap(cmd.getChunkMap() + "-REC"); sendMessage(cmd); ICountDownLatch latch = sessionLatch(cmd); try { log.info("[DFSS#" + cmd.getSessionId() + "] Preparing cluster for file distribution.. "); boolean b = latch.await(config.getClusterPreparationTime().getDuration(), config.getClusterPreparationTime().getUnit()); if (!b) { cmd.setCommand(DFSSCommand.CMD_ABORT_JOB); sendMessage(cmd); throw new IOException("[" + cmd.getSessionId() + "] Unable to prepare cluster for distribution in " + config + ". Job aborted!"); } } catch (InterruptedException e) { log.error("Aborting job on being interrupted unexpectedly", e); cmd.setCommand(DFSSCommand.CMD_ABORT_JOB); sendMessage(cmd); throw new InterruptedIOException("[" + cmd.getSessionId() + "] InterruptedException. Job aborted!"); } finally { latch.destroy(); } hzService.setMapConfiguration(recordMapCfg, cmd.getRecordMap()); log.info("[DFSS#" + cmd.getSessionId() + "] Cluster preparation complete.."); return cmd; } private final Map<String, FileChunkCollector> distributors = new WeakHashMap<>(); /** * * @param sessionId */ private void removeDistributor(String sessionId) { FileChunkCollector dist = distributors.remove(sessionId); if (dist != null) { clean(dist); } } private static void clean(FileChunkCollector dist) { dist.close(); dist.destroyTempDO(); } /** * */ private void removeAllDistributor() { for (Iterator<FileChunkCollector> iter = distributors.values().iterator(); iter.hasNext();) { FileChunkCollector afd = iter.next(); clean(afd); iter.remove(); } } private FileChunkCollector createChunkCollector(DFSSCommand cmd) { FileChunkCollector dist = new FileChunkCollector(hzService, cmd.getRecordMap(), cmd.getChunkMap(), cmd.getSessionId(), cmd.getConfig()); distributors.put(cmd.getSessionId(), dist); log.info("[DFSS#" + cmd.getSessionId() + "] New distribution task created for session.."); return dist; } @Override public void onMessage(Message<DFSSCommand> message) { DFSSCommand cmd = message.getMessageObject(); if (DFSSCommand.CMD_INIT_ASCII_RCVRS.equals(cmd.getCommand())) { if (!message.getPublishingMember().localMember()) { //will be closed by self createChunkCollector(cmd); sessionLatch(cmd).countDown(); } } else if (DFSSCommand.CMD_ABORT_JOB.equals(cmd.getCommand())) { removeDistributor(cmd.getSessionId()); } } @Override public String topic() { return DFSSCommand.class.getSimpleName().toUpperCase(); } @Override public void sendMessage(DFSSCommand message) { hzService.publish(message, topic()); } }