Examples with Random java.util.Random used on opensource projects

Example 31 with Random

use of java.util.Random in project flink by apache.

the class AtomicDisposableReferenceCounterTest method testConcurrentIncrementAndDecrement.

@Test
public void testConcurrentIncrementAndDecrement() throws InterruptedException, ExecutionException, TimeoutException {
    final Random random = new Random();
    final ExecutorService executor = Executors.newFixedThreadPool(2);
    try {
        final MockIncrementer incrementer = new MockIncrementer();
        final MockDecrementer decrementer = new MockDecrementer();
        // Repeat this to provoke races
        for (int i = 0; i < 256; i++) {
            final AtomicDisposableReferenceCounter counter = new AtomicDisposableReferenceCounter();
            incrementer.setCounter(counter);
            decrementer.setCounter(counter);
            counter.increment();
            // Randomly decide which one should be first as the first task usually will win the race
            boolean incrementFirst = random.nextBoolean();
            Future<Boolean> success1 = executor.submit(incrementFirst ? incrementer : decrementer);
            Future<Boolean> success2 = executor.submit(incrementFirst ? decrementer : incrementer);
            // Only one of the two should win the race and return true
            assertTrue(success1.get() ^ success2.get());
        }
    } finally {
        executor.shutdownNow();
    }
}

Example 32 with Random

use of java.util.Random in project flink by apache.

the class AbstractStreamOperatorTest method getKeyInKeyGroupRange.

private static int getKeyInKeyGroupRange(KeyGroupRange range, int maxParallelism) {
    Random rand = new Random(System.currentTimeMillis());
    int result = rand.nextInt();
    while (!range.contains(KeyGroupRangeAssignment.assignToKeyGroup(result, maxParallelism))) {
        result = rand.nextInt();
    }
    return result;
}

Example 33 with Random

use of java.util.Random in project flink by apache.

the class HeapInternalTimerServiceTest method getKeyInKeyGroup.

private static int getKeyInKeyGroup(int keyGroup, int maxParallelism) {
    Random rand = new Random(System.currentTimeMillis());
    int result = rand.nextInt();
    while (KeyGroupRangeAssignment.assignToKeyGroup(result, maxParallelism) != keyGroup) {
        result = rand.nextInt();
    }
    return result;
}

Example 34 with Random

use of java.util.Random in project flink by apache.

the class KeyMapTest method testPutAndGetRandom.

@Test
public void testPutAndGetRandom() {
    try {
        final KeyMap<Integer, Integer> map = new KeyMap<>();
        final Random rnd = new Random();
        final long seed = rnd.nextLong();
        final int numElements = 10000;
        final HashMap<Integer, Integer> groundTruth = new HashMap<>();
        rnd.setSeed(seed);
        for (int i = 0; i < numElements; i++) {
            Integer key = rnd.nextInt();
            Integer value = rnd.nextInt();
            if (rnd.nextBoolean()) {
                groundTruth.put(key, value);
                map.put(key, value);
            }
        }
        rnd.setSeed(seed);
        for (int i = 0; i < numElements; i++) {
            Integer key = rnd.nextInt();
            // skip these, evaluating it is tricky due to duplicates
            rnd.nextInt();
            rnd.nextBoolean();
            Integer expected = groundTruth.get(key);
            if (expected == null) {
                assertNull(map.get(key));
            } else {
                Integer contained = map.get(key);
                assertNotNull(contained);
                assertEquals(expected, contained);
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
        fail(e.getMessage());
    }
}

Example 35 with Random

use of java.util.Random in project flink by apache.

the class SpilledBufferOrEventSequenceTest method testMultipleSequences.

@Test
public void testMultipleSequences() {
    File secondFile = null;
    FileChannel secondChannel = null;
    try {
        // create the second file channel
        secondFile = File.createTempFile("testdata", "tmp");
        secondChannel = new RandomAccessFile(secondFile, "rw").getChannel();
        final Random rnd = new Random();
        final Random bufferRnd = new Random();
        final long bufferSeed = rnd.nextLong();
        bufferRnd.setSeed(bufferSeed);
        final int numEventsAndBuffers1 = 272;
        final int numEventsAndBuffers2 = 151;
        final int numChannels = 1656;
        final ArrayList<BufferOrEvent> events1 = new ArrayList<BufferOrEvent>(128);
        final ArrayList<BufferOrEvent> events2 = new ArrayList<BufferOrEvent>(128);
        for (int i = 0; i < numEventsAndBuffers1; i++) {
            boolean isEvent = rnd.nextDouble() < 0.05d;
            if (isEvent) {
                events1.add(generateAndWriteEvent(fileChannel, rnd, numChannels));
            } else {
                writeBuffer(fileChannel, bufferRnd.nextInt(pageSize) + 1, bufferRnd.nextInt(numChannels));
            }
        }
        for (int i = 0; i < numEventsAndBuffers2; i++) {
            boolean isEvent = rnd.nextDouble() < 0.05d;
            if (isEvent) {
                events2.add(generateAndWriteEvent(secondChannel, rnd, numChannels));
            } else {
                writeBuffer(secondChannel, bufferRnd.nextInt(pageSize) + 1, bufferRnd.nextInt(numChannels));
            }
        }
        // reset and create reader
        fileChannel.position(0L);
        secondChannel.position(0L);
        bufferRnd.setSeed(bufferSeed);
        SpilledBufferOrEventSequence seq1 = new SpilledBufferOrEventSequence(tempFile, fileChannel, buffer, pageSize);
        SpilledBufferOrEventSequence seq2 = new SpilledBufferOrEventSequence(secondFile, secondChannel, buffer, pageSize);
        // read and validate the sequence 1
        seq1.open();
        int numEvent = 0;
        for (int i = 0; i < numEventsAndBuffers1; i++) {
            BufferOrEvent next = seq1.getNext();
            if (next.isEvent()) {
                BufferOrEvent expected = events1.get(numEvent++);
                assertEquals(expected.getEvent(), next.getEvent());
                assertEquals(expected.getChannelIndex(), next.getChannelIndex());
            } else {
                validateBuffer(next, bufferRnd.nextInt(pageSize) + 1, bufferRnd.nextInt(numChannels));
            }
        }
        assertNull(seq1.getNext());
        assertEquals(events1.size(), numEvent);
        // read and validate the sequence 2
        seq2.open();
        numEvent = 0;
        for (int i = 0; i < numEventsAndBuffers2; i++) {
            BufferOrEvent next = seq2.getNext();
            if (next.isEvent()) {
                BufferOrEvent expected = events2.get(numEvent++);
                assertEquals(expected.getEvent(), next.getEvent());
                assertEquals(expected.getChannelIndex(), next.getChannelIndex());
            } else {
                validateBuffer(next, bufferRnd.nextInt(pageSize) + 1, bufferRnd.nextInt(numChannels));
            }
        }
        assertNull(seq2.getNext());
        assertEquals(events2.size(), numEvent);
    } catch (Exception e) {
        e.printStackTrace();
        fail(e.getMessage());
    } finally {
        if (secondChannel != null) {
            try {
                secondChannel.close();
            } catch (IOException e) {
            // ignore here
            }
        }
        if (secondFile != null) {
            //noinspection ResultOfMethodCallIgnored
            secondFile.delete();
        }
    }
}