Example usage for java.util.concurrent Future get

Introduction

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

Prototype

V get() throws InterruptedException, ExecutionException;

Source Link

Document

Waits if necessary for the computation to complete, and then retrieves its result.

Usage

From source file:Main.java

static <T> List<T> submit(List<? extends Callable<T>> taskList, final String taskName) throws Exception {

    List<Future<T>> futureList = new ArrayList();

    List<T> result = new ArrayList<>();

    ExecutorService pool = newFixedThreadPool(taskList.size(), taskName);

    for (Callable<T> callable : taskList) {
        futureList.add(pool.submit(callable));
    }/*w w w .ja va2  s  .  c  o m*/

    pool.shutdown();

    for (Future<T> f : futureList) {
        try {
            result.add(f.get());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    return result;
}

From source file:Main.java

/**
 * Await all of the future tasks indefinitely.
 * The exceptions are combined into a single exception
 * (by adding subsequent exceptions as addsuppressed).
 * @param tasks the sequence of tasks//from   w w  w .  j  ava2  s  .c om
 * @throws ExecutionException if the task failed
 * @throws InterruptedException if the wait was interrupted
 */
public static void awaitAll(Iterable<? extends Future<?>> tasks)
        throws ExecutionException, InterruptedException {
    ExecutionException ee = null;
    InterruptedException ie = null;
    for (Future<?> f : tasks) {
        try {
            f.get();
        } catch (ExecutionException ex) {
            if (ee != null) {
                ee.addSuppressed(ex);
            } else {
                ee = ex;
            }
        } catch (InterruptedException ex) {
            if (ie != null) {
                ie.addSuppressed(ex);
            } else {
                ie = ex;
            }
        }
    }
    if (ee != null && ie != null) {
        ee.addSuppressed(ie);
        throw ee;
    } else if (ee != null) {
        throw ee;
    } else if (ie != null) {
        throw ie;
    }
}

From source file:Main.java

/**
 * Verify that no assertions have failed inside a future.
 * Used for unit tests that spawn threads. E.g.,
 * <p>/*  w ww .j  av  a2s  .c  om*/
 * <code>
 *   List<Future<Void>> results = Lists.newArrayList();
 *   Future<Void> f = executor.submit(new Callable<Void> {
 *     public Void call() {
 *       assertTrue(someMethod());
 *     }
 *   });
 *   results.add(f);
 *   assertOnFutures(results);
 * </code>
 * @param threadResults A list of futures
 * @param <T>
 * @throws InterruptedException If interrupted when waiting for a result
 *                              from one of the futures
 * @throws ExecutionException If an exception other than AssertionError
 *                            occurs inside any of the futures
 */
public static <T> void assertOnFutures(List<Future<T>> threadResults)
        throws InterruptedException, ExecutionException {
    for (Future<T> threadResult : threadResults) {
        try {
            threadResult.get();
        } catch (ExecutionException e) {
            if (e.getCause() instanceof AssertionError) {
                throw (AssertionError) e.getCause();
            }
            throw e;
        }
    }
}

From source file:Main.java

public static void invokeAll(final List<Runnable> tasks, final ExecutorService executor)
        throws InterruptedException, ExecutionException {
    ExecutionException saved = null;

    if (executor != null) {
        final List<Future<?>> futures = new ArrayList<>();
        for (final Runnable task : tasks)
            futures.add(executor.submit(task));

        for (final Future<?> future : futures) {
            try {
                future.get();
            } catch (InterruptedException e) {
                throw e;
            } catch (ExecutionException e) {
                if (saved == null) {
                    saved = e;/*from   ww w  .  j  a v  a2s. c om*/
                } else {
                    saved.addSuppressed(e);
                }
            }
        }
    } else {
        for (final Runnable task : tasks) {
            try {
                task.run();
            } catch (Exception e) {
                if (saved == null) {
                    saved = new ExecutionException(e);
                } else {
                    saved.addSuppressed(e);
                }
            }
        }
    }

    if (saved != null)
        throw saved;
}

From source file:Test.java

private static void serverStart() {
    try {/*from  ww  w . j  a v  a  2  s .  c om*/
        InetSocketAddress hostAddress = new InetSocketAddress(InetAddress.getByName("127.0.0.1"), 2583);
        AsynchronousServerSocketChannel serverSocketChannel = AsynchronousServerSocketChannel.open()
                .bind(hostAddress);
        Future<AsynchronousSocketChannel> serverFuture = serverSocketChannel.accept();
        final AsynchronousSocketChannel clientSocket = serverFuture.get();
        if ((clientSocket != null) && (clientSocket.isOpen())) {
            InputStream connectionInputStream = Channels.newInputStream(clientSocket);
            ObjectInputStream ois = null;
            ois = new ObjectInputStream(connectionInputStream);
            while (true) {
                Object object = ois.readObject();
                if (object.equals("EOF")) {
                    clientSocket.close();
                    break;
                }
                System.out.println("Received :" + object);
            }
            ois.close();
            connectionInputStream.close();
        }

    } catch (Exception e) {
        e.printStackTrace();
    }
}

From source file:org.edgexfoundry.EdgeXConfigWatcherApplication.java

public static void registerWatcher(List<CatalogService> services, String notificationPath) {
    try (CloseableHttpAsyncClient httpClient = HttpAsyncClients.createDefault();) {
        httpClient.start();//from w  w  w.java 2  s. c  o  m
        for (CatalogService service : services) {
            LOGGER.info("Attempting registration of {} to: {}", service.getServiceName(), notificationPath);
            URL serviceNotificationURL = new URL(notificationProtocol, service.getAddress(),
                    service.getServicePort(), notificationPath);
            HttpGet request = new HttpGet(serviceNotificationURL.toURI());
            Future<HttpResponse> future = httpClient.execute(request, null);
            future.get();
            LOGGER.info("Registered {} @ {}", service.getServiceName(), notificationPath);
        }
    } catch (URISyntaxException e) {
        LOGGER.error("URI Syntax issue: " + e.getMessage());
    } catch (InterruptedException e) {
        LOGGER.error("Interrupted process: " + e.getMessage());
        Thread.currentThread().interrupt();
    } catch (ExecutionException e) {
        LOGGER.error("Execution problem: " + e.getMessage());
    } catch (IOException e) {
        LOGGER.error("IO problem: " + e.getMessage());
    }
}

From source file:Main.java

public static <V> V getUninterruptibly(Future<V> future) throws ExecutionException {
    boolean interrupted = false;
    try {/* www . j  ava 2  s  .c o  m*/
        while (true) {
            try {
                return future.get();
            } catch (InterruptedException e) {
                interrupted = true;
            }
        }
    } finally {
        if (interrupted) {
            Thread.currentThread().interrupt();
        }
    }
}

From source file:cn.clxy.codes.upload.UploadFileService.java

private static String checkFuture(Future<String> future) {

    try {/*from   w  w  w  .j av  a 2 s. c om*/
        String result = future.get();
        log.debug(result + " is done.");
        return result;
    } catch (InterruptedException e) {
        Thread.currentThread().interrupt();
        return null;
    } catch (ExecutionException e) {
        throw new RuntimeException(e.getCause());
    }
}

From source file:Main.java

public static <T> T getFutureResult(Callable<T> task, long timeout) throws TimeoutException {
    try {//  ww w.j a v a  2  s  .com
        ExecutorService executor = Executors.newFixedThreadPool(1);
        Future<T> future = executor.submit(task);
        T result = null;
        if (timeout <= 0) {
            System.out.println("get wait forever");
            result = future.get();
        } else {
            System.out.println("get wait " + timeout);
            result = future.get(timeout, TimeUnit.MILLISECONDS);
        }
        return result;
    } catch (java.util.concurrent.TimeoutException ex) {
        throw ex;
    } catch (Exception ex) {
        throw new RuntimeException(ex);
    }
}

From source file:com.bigdata.dastor.streaming.StreamOut.java

/**
 * Split out files for all tables on disk locally for each range and then stream them to the target endpoint.
*///from   w  w w.ja  v a2 s .c o m
public static void transferRanges(InetAddress target, String tableName, Collection<Range> ranges,
        Runnable callback) {
    assert ranges.size() > 0;

    logger.debug("Beginning transfer process to " + target + " for ranges " + StringUtils.join(ranges, ", "));

    /*
     * (1) dump all the memtables to disk.
     * (2) anticompaction -- split out the keys in the range specified
     * (3) transfer the data.
    */
    try {
        Table table = Table.open(tableName);
        logger.info("Flushing memtables for " + tableName + "...");
        for (Future f : table.flush()) {
            try {
                f.get();
            } catch (InterruptedException e) {
                throw new RuntimeException(e);
            } catch (ExecutionException e) {
                throw new RuntimeException(e);
            }
        }
        logger.info("Performing anticompaction ...");
        /* Get the list of files that need to be streamed */
        transferSSTables(target, table.forceAntiCompaction(ranges, target), tableName); // SSTR GC deletes the file when done
    } catch (IOException e) {
        throw new IOError(e);
    } finally {
        StreamOutManager.remove(target);
    }
    if (callback != null)
        callback.run();
}