Example usage for java.util.concurrent Semaphore Semaphore

Introduction

In this page you can find the example usage for java.util.concurrent Semaphore Semaphore.

Prototype

public Semaphore(int permits)

Source Link

Document

Creates a Semaphore with the given number of permits and nonfair fairness setting.

Usage

From source file:com.bt.aloha.batchtest.v2.StackManagerSyncronizationSemaphoreImpl.java

public void initialize(int count, int max) {
    this.max = max;
    this.semaphore = new Semaphore(count);
    log.info("Initializing Syncronization semaphore to " + count);
}

From source file:edu.iu.harp.schstatic.StaticScheduler.java

@SuppressWarnings("unchecked")
public StaticScheduler(List<T> tasks) {
    threads = null;// w  ww  .j a v a2  s  .  c o  m
    barrier1 = new Semaphore(0);
    numTaskMonitors = tasks.size();
    taskMonitors = new TaskMonitor[numTaskMonitors];
    submitter = new Submitter<>(taskMonitors);
    int i = 0;
    for (T task : tasks) {
        taskMonitors[i] = new TaskMonitor<>(i, task, submitter, numTaskMonitors, barrier1);
        i++;
    }
}

From source file:edu.iu.harp.schdynamic.TaskMonitor.java

TaskMonitor(BlockingDeque<Input<I>> inQueue, BlockingQueue<Output<O>> outQueue, T task, Semaphore barrier1) {
    inputQueue = inQueue;/*from   w  w w. ja v a2s. c om*/
    outputQueue = outQueue;
    taskObject = task;
    this.barrier1 = barrier1;
    this.barrier2 = new Semaphore(0);
}

From source file:core.service.bus.socket.SocketWrapper.java

public SocketWrapper(Socket socket) {
    super();
    this.socket = socket;
    lock = new Semaphore(1);
}

From source file:frames.LoginFrame.java

public LoginFrame() {

    initComponents();//from w ww. ja  v  a2s . co  m

    //Enable calling the clients
    System.setSecurityManager(null);

    //Create semaphore with a single permission
    semaphore = new Semaphore(1);

    //Centralizes frame
    setLocationRelativeTo(null);

    //Make Login frame visible
    setVisible(true);
}

From source file:org.wso2.carbon.event.publisher.core.internal.BlockingEventQueue.java

public BlockingEventQueue(int maxSizeInMb, int maxNumOfEvents) {
    super(maxNumOfEvents);
    this.maxSizeInBytes = maxSizeInMb * 1000000;
    this.semaphore = new Semaphore(1);
    this.currentSize = new AtomicInteger(0);
    this.lock = new Object();
    this.currentEventSize = 0;
}

From source file:fr.aliasource.webmail.common.cache.FileCache.java

protected FileCache(IAccount account, String category, String cacheName, IDirectCommand<W> command) {
    super(account);
    this.command = command;
    updateLock = new Semaphore(1);
    this.category = category;
    this.cacheName = cacheName;
    this.cDirectory = account.getCache().getCachePath() + File.separator + category;
    new File(cDirectory).mkdirs();
    this.cFile = new File(cDirectory + File.separator + cacheName + ".xml");
    this.logger = LogFactory.getLog(getClass());

    if (!exists()) {
        initEmpty();/*from  w ww  . j  a  va  2 s .  co  m*/
    }
}

From source file:com.pinterest.rocksplicator.controller.WorkerPoolTest.java

@Test
public void testAssignSingleTask() throws Exception {
    Semaphore idleWorkersSemaphore = new Semaphore(0);
    ThreadPoolExecutor threadPoolExecutor = new ThreadPoolExecutor(1, 1, 0, TimeUnit.SECONDS,
            new ArrayBlockingQueue<Runnable>(1));
    WorkerPool workerPool = new WorkerPool(threadPoolExecutor, idleWorkersSemaphore, new TaskQueue() {
    });/* w w  w  .ja va  2  s  . c  o m*/
    workerPool.assignTask(getSleepIncrementTask());
    Thread.sleep(2000);
    Assert.assertEquals(1, SleepIncrementTask.executionCounter.intValue());
    workerPool.assignTask(getSleepIncrementTask());
    Thread.sleep(2000);
    Assert.assertEquals(2, SleepIncrementTask.executionCounter.intValue());
    Assert.assertEquals(2, idleWorkersSemaphore.availablePermits());
}

From source file:org.commoncrawl.service.queryserver.master.S3Helper.java

public static ArcFileItem retrieveArcFileItem(ArchiveInfo archiveInfo, EventLoop eventLoop) throws IOException {

    // the default bucket id 
    String bucketId = "commoncrawl-crawl-002";

    //ok, see if we need to switch buckets 
    if (archiveInfo.getCrawlNumber() == 1) {
        bucketId = "commoncrawl";
    }//from w  ww  . j a  v a  2  s.c o m

    S3Downloader downloader = new S3Downloader(bucketId, "", "", false);

    // now activate the segment log ... 
    final Semaphore downloadCompleteSemaphore = new Semaphore(0);
    final StreamingArcFileReader arcFileReader = new StreamingArcFileReader(false);
    //arcFileReader.setArcFileHasHeaderItemFlag(false);

    // create a buffer list we will append incoming content into ... 
    final LinkedList<ByteBuffer> bufferList = new LinkedList<ByteBuffer>();

    downloader.initialize(new S3Downloader.Callback() {

        @Override
        public boolean contentAvailable(int itemId, String itemKey, NIOBufferList contentBuffer) {
            LOG.info("ContentQuery contentAvailable called for Item:" + itemKey + " totalBytesAvailable:"
                    + contentBuffer.available());

            try {
                while (contentBuffer.available() != 0) {
                    bufferList.add(contentBuffer.read());
                }
                return true;
            } catch (IOException e) {
                LOG.error(CCStringUtils.stringifyException(e));
                return false;
            }
        }

        @Override
        public void downloadComplete(int itemId, String itemKey) {
            LOG.info("S3 Download Complete for item:" + itemKey);
            downloadCompleteSemaphore.release();
        }

        @Override
        public void downloadFailed(int itemId, String itemKey, String errorCode) {
            LOG.info("S3 Download Failed for item:" + itemKey);
            downloadCompleteSemaphore.release();
        }

        @Override
        public boolean downloadStarting(int itemId, String itemKey, int contentLength) {
            LOG.info("ContentQuery DownloadStarting for Item:" + itemKey + " contentLength:" + contentLength);
            return true;
        }

    }, eventLoop);

    LOG.info("Starting request for Item:"
            + hdfsNameToS3ArcFileName(archiveInfo.getArcfileDate(), archiveInfo.getArcfileIndex()) + " Offset:"
            + archiveInfo.getArcfileOffset());

    int sizeToRetrieve = (archiveInfo.getCompressedSize() != 0) ? archiveInfo.getCompressedSize() : 30000;
    sizeToRetrieve += 10;

    downloader.fetchPartialItem(
            hdfsNameToS3ArcFileName(archiveInfo.getArcfileDate(), archiveInfo.getArcfileIndex()),
            archiveInfo.getArcfileOffset() - 10, sizeToRetrieve);
    downloadCompleteSemaphore.acquireUninterruptibly();

    if (bufferList.size() == 0) {
        return null;
    }

    ByteBuffer firstBuffer = bufferList.getFirst();
    if (firstBuffer != null) {
        int offsetToGZIPHeader = scanForGZIPHeader(firstBuffer.duplicate());
        if (offsetToGZIPHeader != -1) {
            firstBuffer.position(offsetToGZIPHeader);
            LOG.info("*** Offset to GZIP Header:" + offsetToGZIPHeader);
        } else {
            LOG.error("*** Failed to find GZIP Header offset");
        }
    }

    // now try to decode content if possible
    for (ByteBuffer buffer : bufferList) {
        LOG.info("Adding Buffer of Size:" + buffer.remaining() + " Position:" + buffer.position() + " Limit:"
                + buffer.limit());
        arcFileReader.available(buffer);
    }

    ArcFileItem item = arcFileReader.getNextItem();

    if (item != null) {
        LOG.info("Request Returned item:" + item.getUri());
        LOG.info("Uncompressed Size:" + item.getContent().getCount());
    }
    return item;
}

From source file:org.wso2.carbon.event.receiver.core.internal.management.BlockingEventQueue.java

public BlockingEventQueue(int maxSizeInMb, int maxNumOfEvents) {
    this.maxSizeInBytes = maxSizeInMb * 1000000; // to convert to bytes
    this.queue = new LinkedBlockingQueue<>(maxNumOfEvents);
    this.semaphore = new Semaphore(1);
    this.currentSize = new AtomicInteger(0);
    this.lock = new Object();
    this.currentEventSize = 0;
}