Examples with Consumer java8.util.function.Consumer used on opensource projects

Example 1 with Consumer

use of java8.util.function.Consumer in project streamsupport by stefan-zobel.

the class StreamSpliteratorTest method testDoubleSplitting.

// 
public void testDoubleSplitting() {
    List<Consumer<DoubleStream>> terminalOps = Arrays.asList(s -> s.toArray(), s -> s.forEach(e -> {
    }), s -> s.reduce(java8.lang.Doubles::sum));
    List<UnaryOperator<DoubleStream>> intermediateOps = Arrays.asList(s -> s.parallel(), // The following ensures the wrapping spliterator is tested
    s -> s.map(i -> i).parallel());
    for (int i = 0; i < terminalOps.size(); i++) {
        Consumer<DoubleStream> terminalOp = terminalOps.get(i);
        setContext("termOpIndex", i);
        for (int j = 0; j < intermediateOps.size(); j++) {
            UnaryOperator<DoubleStream> intermediateOp = intermediateOps.get(j);
            setContext("intOpIndex", j);
            for (boolean proxyEstimateSize : new boolean[] { false, true }) {
                setContext("proxyEstimateSize", proxyEstimateSize);
                // Size is assumed to be larger than the target size for no splitting
                // @@@ Need way to obtain the target size
                Spliterator.OfDouble sp = intermediateOp.apply(IntStreams.range(0, 1000).asDoubleStream()).spliterator();
                ProxyNoExactSizeSpliterator.OfDouble psp = new ProxyNoExactSizeSpliterator.OfDouble(sp, proxyEstimateSize);
                DoubleStream s = StreamSupport.doubleStream(psp, true);
                terminalOp.accept(s);
                Assert.assertTrue(psp.splits > 0, String.format("Number of splits should be greater that zero when proxyEstimateSize is %s", proxyEstimateSize));
                Assert.assertTrue(psp.prefixSplits > 0, String.format("Number of non-null prefix splits should be greater that zero when proxyEstimateSize is %s", proxyEstimateSize));
                Assert.assertTrue(psp.sizeOnTraversal < 1000, String.format("Size on traversal of last split should be less than the size of the list, %d, when proxyEstimateSize is %s", 1000, proxyEstimateSize));
            }
        }
    }
}

Example 2 with Consumer

use of java8.util.function.Consumer in project streamsupport by stefan-zobel.

the class Collection8Test method testElementRemovalDuringTraversal.

/**
 * All elements removed in the middle of CONCURRENT traversal.
 */
@SuppressWarnings({ "unchecked", "rawtypes" })
@Test(dataProvider = "Source")
public void testElementRemovalDuringTraversal(String description, Supplier<CollectionImplementation> sci) {
    CollectionImplementation impl = sci.get();
    if (HAS_JAVA8_SPLITERATOR_BUG && LinkedBlockingQueue.class.equals(impl.klazz())) {
        // https://bugs.openjdk.java.net/browse/JDK-8171051
        return;
    }
    Collection<Object> c = impl.emptyCollection();
    ThreadLocalRandom rnd = ThreadLocalRandom.current();
    int n = rnd.nextInt(6);
    ArrayList copy = new ArrayList();
    for (int i = 0; i < n; i++) {
        Object x = impl.makeElement(i);
        copy.add(x);
        c.add(x);
    }
    ArrayList iterated = new ArrayList();
    ArrayList spliterated = new ArrayList();
    Spliterator<?> s = Spliterators.spliterator(c);
    Iterator<?> it = c.iterator();
    for (int i = rnd.nextInt(n + 1); --i >= 0; ) {
        assertTrue(s.tryAdvance(spliterated::add));
        if (rnd.nextBoolean())
            assertTrue(it.hasNext());
        iterated.add(it.next());
    }
    Consumer alwaysThrows = e -> {
        throw new AssertionError();
    };
    if (s.hasCharacteristics(Spliterator.CONCURRENT)) {
        // TODO: many more removal methods
        c.clear();
        if (testImplementationDetails && !(c instanceof java.util.concurrent.ArrayBlockingQueue)) {
            if (rnd.nextBoolean())
                assertFalse(s.tryAdvance(alwaysThrows));
            else
                s.forEachRemaining(alwaysThrows);
        }
        if (it.hasNext())
            iterated.add(it.next());
        if (rnd.nextBoolean())
            assertIteratorExhausted(it);
    }
    assertTrue(copy.containsAll(iterated));
    assertTrue(copy.containsAll(spliterated));
}

Example 3 with Consumer

use of java8.util.function.Consumer in project streamsupport by stefan-zobel.

the class Collection8Test method emptyMeansEmpty.

@SuppressWarnings({ "rawtypes", "unchecked" })
void emptyMeansEmpty(Collection<?> c, Supplier<CollectionImplementation> sci) throws InterruptedException {
    assertTrue(c.isEmpty());
    assertEquals(0, c.size());
    assertEquals("[]", c.toString());
    if (c instanceof List<?>) {
        List x = (List) c;
        assertEquals(1, x.hashCode());
        assertEquals(x, Collections.emptyList());
        assertEquals(Collections.emptyList(), x);
        assertEquals(-1, x.indexOf(sci.get().makeElement(86)));
        assertEquals(-1, x.lastIndexOf(sci.get().makeElement(99)));
        assertThrows(IndexOutOfBoundsException.class, () -> x.get(0), () -> x.set(0, sci.get().makeElement(42)));
    } else if (c instanceof Set<?>) {
        assertEquals(0, c.hashCode());
        assertEquals(c, Collections.emptySet());
        assertEquals(Collections.emptySet(), c);
    }
    {
        Object[] a = c.toArray();
        assertEquals(0, a.length);
        assertSame(Object[].class, a.getClass());
    }
    {
        Object[] a = new Object[0];
        assertSame(a, c.toArray(a));
    }
    {
        Integer[] a = new Integer[0];
        assertSame(a, c.toArray(a));
    }
    {
        Integer[] a = { 1, 2, 3 };
        assertSame(a, c.toArray(a));
        assertNull(a[0]);
        assertSame(2, a[1]);
        assertSame(3, a[2]);
    }
    assertIteratorExhausted(c.iterator());
    Consumer alwaysThrows = e -> {
        throw new AssertionError();
    };
    Iterables.forEach(c, alwaysThrows);
    Iterators.forEachRemaining(c.iterator(), alwaysThrows);
    Spliterators.spliterator(c).forEachRemaining(alwaysThrows);
    assertFalse(Spliterators.spliterator(c).tryAdvance(alwaysThrows));
    if (Spliterators.spliterator(c).hasCharacteristics(Spliterator.SIZED))
        assertEquals(0, Spliterators.spliterator(c).estimateSize());
    assertFalse(c.contains(bomb()));
    assertFalse(c.remove(bomb()));
    if (c instanceof Queue) {
        Queue<?> q = (Queue<?>) c;
        assertNull(q.peek());
        assertNull(q.poll());
    }
    if (c instanceof Deque) {
        Deque<?> d = (Deque<?>) c;
        assertNull(d.peekFirst());
        assertNull(d.peekLast());
        assertNull(d.pollFirst());
        assertNull(d.pollLast());
        assertIteratorExhausted(d.descendingIterator());
        Iterators.forEachRemaining(d.descendingIterator(), alwaysThrows);
        assertFalse(d.removeFirstOccurrence(bomb()));
        assertFalse(d.removeLastOccurrence(bomb()));
    }
    if (c instanceof BlockingQueue) {
        BlockingQueue<?> q = (BlockingQueue<?>) c;
        assertNull(q.poll(randomExpiredTimeout(), randomTimeUnit()));
    }
    if (c instanceof BlockingDeque) {
        BlockingDeque<?> q = (BlockingDeque<?>) c;
        assertNull(q.pollFirst(randomExpiredTimeout(), randomTimeUnit()));
        assertNull(q.pollLast(randomExpiredTimeout(), randomTimeUnit()));
    }
}

Example 4 with Consumer

use of java8.util.function.Consumer in project streamsupport by stefan-zobel.

the class Collection8Test method testStickySpliteratorExhaustion.

/**
 * Concurrent Spliterators, once exhausted, stay exhausted.
 */
@SuppressWarnings({ "rawtypes", "unchecked" })
@Test(dataProvider = "Source")
public void testStickySpliteratorExhaustion(String description, Supplier<CollectionImplementation> sci) throws Throwable {
    CollectionImplementation impl = sci.get();
    if (HAS_JAVA8_SPLITERATOR_BUG && PriorityBlockingQueue.class.equals(impl.klazz())) {
        // https://bugs.openjdk.java.net/browse/JDK-8172023
        return;
    }
    if (!impl.isConcurrent())
        return;
    if (!testImplementationDetails)
        return;
    final ThreadLocalRandom rnd = ThreadLocalRandom.current();
    final Consumer<?> alwaysThrows = e -> {
        throw new AssertionError();
    };
    final Collection c = impl.emptyCollection();
    final Spliterator s = Spliterators.spliterator(c);
    if (rnd.nextBoolean()) {
        assertFalse(s.tryAdvance(alwaysThrows));
    } else {
        s.forEachRemaining(alwaysThrows);
    }
    final Object one = impl.makeElement(1);
    // Spliterator should not notice added element
    c.add(one);
    if (rnd.nextBoolean()) {
        assertFalse(s.tryAdvance(alwaysThrows));
    } else {
        s.forEachRemaining(alwaysThrows);
    }
}

Example 5 with Consumer

use of java8.util.function.Consumer in project streamsupport by stefan-zobel.

the class Collection8Test method testForEach.

/**
 * collection.forEach returns elements in the collection
 */
@SuppressWarnings({ "rawtypes", "unchecked" })
@Test(dataProvider = "Source")
public void testForEach(String description, Supplier<CollectionImplementation> sci) throws Throwable {
    CollectionImplementation impl = sci.get();
    final Collection c = impl.emptyCollection();
    // final AtomicLong count = new AtomicLong(0L);
    final Object x = impl.makeElement(1);
    final Object y = impl.makeElement(2);
    final ArrayList found = new ArrayList();
    Consumer<Object> spy = o -> found.add(o);
    Iterables.forEach(c, spy);
    assertTrue(found.isEmpty());
    assertTrue(c.add(x));
    Iterables.forEach(c, spy);
    assertEquals(Collections.singletonList(x), found);
    found.clear();
    assertTrue(c.add(y));
    Iterables.forEach(c, spy);
    assertEquals(2, found.size());
    assertTrue(found.contains(x));
    assertTrue(found.contains(y));
    found.clear();
    c.clear();
    Iterables.forEach(c, spy);
    assertTrue(found.isEmpty());
}