Example usage for java.util.concurrent.locks Lock lock

Introduction

In this page you can find the example usage for java.util.concurrent.locks Lock lock.

Prototype

lock

Source Link

Usage

From source file:Test.java

public static void main(String[] args) throws Exception {
    Lock myLock = new ReentrantLock();
    Random random = new Random();

    myLock.lock();
    int number = random.nextInt(5);
    int result = 100 / number;
    System.out.println("A result is " + result);
    FileOutputStream file = new FileOutputStream("file.out");
    file.write(result);/*from  w  ww.  j  av a  2s .  co  m*/
    file.close();
}

From source file:Test.java

public static void main(String[] args) {
    final Lock firstLock = new ReentrantLock();
    final Lock secondLock = new ReentrantLock();
    firstLock.lock();
    Thread secondThread = new Thread(new Runnable() {
        public void run() {
            secondLock.lock();//  w  w w  . ja  va2 s.c  o  m
            firstLock.lock();
        }
    });
    secondThread.start();
    try {
        Thread.sleep(250);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
    secondLock.lock();

    secondLock.unlock();
    firstLock.unlock();
}

From source file:Main.java

public static void main(String[] args) {
    int[] runningThreads = { 0 };
    int[] taskcount = { 10 };
    Lock myLock = new ReentrantLock(true);
    int maxThreadQty = 3;
    while ((taskcount[0] > 0) && (runningThreads[0] < maxThreadQty)) {
        myLock.lock();
        runningThreads[0]++;/*from   w w w  .j ava  2  s.c  o  m*/
        myLock.unlock();
        new Thread("T") {
            public void run() {
                myLock.lock();
                taskcount[0]--;
                runningThreads[0]--;
                myLock.unlock();
            }
        }.start();
    }
}

From source file:Main.java

public static void performLocked(Lock lock, Runnable action) {
    lock.lock();
    try {// w  ww.  j a v  a 2 s.  c o  m
        action.run();
    } finally {
        lock.unlock();
    }
}

From source file:Main.java

public static <T> T performLocked(Lock lock, Callable<T> action) {
    lock.lock();
    try {/*  w  w  w. j a  va  2s  . co m*/
        return action.call();
    } catch (RuntimeException e) {
        throw e;
    } catch (Throwable e) {
        throw new RuntimeException(e);
    } finally {
        lock.unlock();
    }
}

From source file:Main.java

/**
 * This methods blocks until the worker is done and returns the result value of the worker.
 * If the worker was canceled an exception will be thrown.
 *
 * @param worker The worker/* w w w  .  ja va2 s .c  om*/
 * @param <T> result type of the worker
 * @return the result
 * @throws InterruptedException if the worker was canceled
 */
public static <T> T waitFor(Worker<T> worker) throws InterruptedException {
    Lock lock = new ReentrantLock();
    Condition condition = lock.newCondition();
    lock.lock();
    try {
        ReadOnlyBooleanProperty doneProperty = createIsDoneProperty(worker);
        if (doneProperty.get()) {
            return worker.getValue();
        } else {
            doneProperty.addListener(e -> {
                boolean locked = lock.tryLock();
                if (locked) {
                    try {
                        condition.signal();
                    } finally {
                        lock.unlock();
                    }
                } else {
                    throw new RuntimeException("Concurreny Error");
                }
            });
            condition.await();
            return worker.getValue();
        }
    } finally {
        lock.unlock();
    }
}

From source file:com.cloudera.oryx.als.serving.generation.Generation.java

private static Solver recomputeSolver(LongObjectMap<float[]> M, Lock readLock) {
    readLock.lock();
    try {/*from ww  w .  j  ava2 s .  c o m*/
        if (M == null || M.isEmpty()) {
            return null;
        }
        RealMatrix MTM = MatrixUtils.transposeTimesSelf(M);
        double infNorm = MTM.getNorm();
        if (infNorm < 1.0) {
            log.warn("X'*X or Y'*Y has small inf norm ({}); try decreasing model.lambda", infNorm);
            throw new IllConditionedSolverException("infNorm: " + infNorm);
        }
        return MatrixUtils.getSolver(MTM);
    } finally {
        readLock.unlock();
    }
}

From source file:com.yahoo.gondola.container.Utils.java

private static void lock(Lock lock) {
    if (lock != null) {
        lock.lock();
    }
}

From source file:com.piggate.sdk.PiggateInfo.java

public static void addInfo(JSONArray bar) {

    Lock l = rwLock2.writeLock();
    l.lock();
    try {//from   www  .  j a v a2 s. c o  m
        registryInfo(bar);
    } catch (Exception ex) {
    } finally {
        l.unlock();
    }
}

From source file:com.piggate.sdk.PiggateOffers.java

public static void addOffers(JSONArray bar) {

    Lock l = rwLock2.writeLock();
    l.lock();
    try {//w w w.  ja  v a 2s  .  c  o m
        registryOffers(bar);
    } catch (Exception ex) {
    } finally {
        l.unlock();
    }
}