/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.github.benmanes.caffeine.cache;
import static org.hamcrest.Matchers.allOf;
import static org.hamcrest.Matchers.empty;
import static org.hamcrest.Matchers.hasSize;
import static org.hamcrest.Matchers.is;
import static org.hamcrest.Matchers.sameInstance;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertThat;
import static org.junit.Assert.assertTrue;
import static org.junit.Assume.assumeThat;
import java.util.Collection;
import java.util.Queue;
import java.util.concurrent.atomic.AtomicBoolean;
import org.hamcrest.Matcher;
import org.jctools.queues.QueueFactory;
import org.jctools.queues.atomic.AtomicQueueFactory;
import org.jctools.queues.spec.ConcurrentQueueSpec;
import org.jctools.queues.spec.Ordering;
import org.jctools.queues.spec.Preference;
import org.jctools.util.Pow2;
import org.junit.Before;
import org.junit.Test;
/**
* @author nitsanw@yahoo.com (Nitsan Wakart)
*/
public abstract class QueueSanityTest {
public static final int SIZE = 8192 * 2;
private final Queue<Integer> queue;
private final ConcurrentQueueSpec spec;
public QueueSanityTest(ConcurrentQueueSpec spec, Queue<Integer> queue) {
this.queue = queue;
this.spec = spec;
}
@Before
public void clear() {
queue.clear();
}
@Test
public void sanity() {
for (int i = 0; i < SIZE; i++) {
assertNull(queue.poll());
assertThat(queue, emptyAndZeroSize());
}
int i = 0;
while (i < SIZE && queue.offer(i)) {
i++;
}
int size = i;
assertEquals(size, queue.size());
if (spec.ordering == Ordering.FIFO) {
// expect FIFO
i = 0;
Integer p;
Integer e;
while ((p = queue.peek()) != null) {
e = queue.poll();
assertEquals(p, e);
assertEquals(size - (i + 1), queue.size());
assertEquals(i++, e.intValue());
}
assertEquals(size, i);
} else {
// expect sum of elements is (size - 1) * size / 2 = 0 + 1 + .... + (size - 1)
int sum = (size - 1) * size / 2;
i = 0;
Integer e;
while ((e = queue.poll()) != null) {
assertEquals(--size, queue.size());
sum -= e;
}
assertEquals(0, sum);
}
assertNull(queue.poll());
assertThat(queue, emptyAndZeroSize());
}
@Test
public void testSizeIsTheNumberOfOffers() {
int currentSize = 0;
while (currentSize < SIZE && queue.offer(currentSize)) {
currentSize++;
assertThat(queue, hasSize(currentSize));
}
}
@Test
public void whenFirstInThenFirstOut() {
assumeThat(spec.ordering, is(Ordering.FIFO));
// Arrange
int i = 0;
while (i < SIZE && queue.offer(i)) {
i++;
}
final int size = queue.size();
// Act
i = 0;
Integer prev;
while ((prev = queue.peek()) != null) {
final Integer item = queue.poll();
assertThat(item, is(prev));
assertThat(queue, hasSize(size - (i + 1)));
assertThat(item, is(i));
i++;
}
// Assert
assertThat(i, is(size));
}
@Test(expected = NullPointerException.class)
public void offerNullResultsInNPE() {
queue.offer(null);
}
@Test
public void whenOfferItemAndPollItemThenSameInstanceReturnedAndQueueIsEmpty() {
assertThat(queue, emptyAndZeroSize());
// Act
final Integer e = 1876876;
queue.offer(e);
assertFalse(queue.isEmpty());
assertEquals(1, queue.size());
final Integer oh = queue.poll();
assertEquals(e, oh);
// Assert
assertThat(oh, sameInstance(e));
assertThat(queue, emptyAndZeroSize());
}
@Test
public void testPowerOf2Capacity() {
assumeThat(spec.isBounded(), is(true));
int n = Pow2.roundToPowerOfTwo(spec.capacity);
for (int i = 0; i < n; i++) {
assertTrue("Failed to insert:" + i, queue.offer(i));
}
assertFalse(queue.offer(n));
}
static final class Val {
public int value;
}
@Test
@SuppressWarnings({"rawtypes", "unchecked"})
public void testHappensBefore() throws Exception {
final AtomicBoolean stop = new AtomicBoolean();
final Queue q = queue;
final Val fail = new Val();
Thread t1 = new Thread(new Runnable() {
@Override public void run() {
while (!stop.get()) {
for (int i = 1; i <= 10; i++) {
Val v = new Val();
v.value = i;
q.offer(v);
}
// slow down the producer, this will make the queue mostly empty encouraging visibility
// issues.
Thread.yield();
}
}
});
Thread t2 = new Thread(new Runnable() {
@Override
public void run() {
while (!stop.get()) {
for (int i = 0; i < 10; i++) {
Val v = (Val) q.peek();
if (v != null && v.value == 0) {
fail.value = 1;
stop.set(true);
}
q.poll();
}
}
}
});
t1.start();
t2.start();
Thread.sleep(1000);
stop.set(true);
t1.join();
t2.join();
assertEquals("reordering detected", 0, fail.value);
}
@Test
public void testSize() throws Exception {
final AtomicBoolean stop = new AtomicBoolean();
final Queue<Integer> q = queue;
final Val fail = new Val();
Thread t1 = new Thread(new Runnable() {
@Override
public void run() {
while (!stop.get()) {
q.offer(1);
q.poll();
}
}
});
Thread t2 = new Thread(new Runnable() {
@Override
public void run() {
while (!stop.get()) {
int size = q.size();
if (size != 0 && size != 1) {
fail.value++;
}
}
}
});
t1.start();
t2.start();
Thread.sleep(1000);
stop.set(true);
t1.join();
t2.join();
assertEquals("Unexpected size observed", 0, fail.value);
}
@Test
public void testPollAfterIsEmpty() throws Exception {
final AtomicBoolean stop = new AtomicBoolean();
final Queue<Integer> q = queue;
final Val fail = new Val();
Thread t1 = new Thread(new Runnable() {
@Override
public void run() {
while (!stop.get()) {
q.offer(1);
// slow down the producer, this will make the queue mostly empty encouraging visibility
// issues.
Thread.yield();
}
}
});
Thread t2 = new Thread(new Runnable() {
@Override
public void run() {
while (!stop.get()) {
if (!q.isEmpty() && q.poll() == null) {
fail.value++;
}
}
}
});
t1.start();
t2.start();
Thread.sleep(1000);
stop.set(true);
t1.join();
t2.join();
assertEquals("Observed no element in non-empty queue", 0, fail.value);
}
public static Object[] makeQueue(int producers, int consumers, int capacity, Ordering ordering,
Queue<Integer> q) {
ConcurrentQueueSpec spec =
new ConcurrentQueueSpec(producers, consumers, capacity, ordering, Preference.NONE);
if (q == null) {
q = QueueFactory.newQueue(spec);
}
return new Object[] {spec, q};
}
public static Object[] makeAtomic(int producers, int consumers, int capacity, Ordering ordering,
Queue<Integer> q) {
ConcurrentQueueSpec spec =
new ConcurrentQueueSpec(producers, consumers, capacity, ordering, Preference.NONE);
if (q == null) {
q = AtomicQueueFactory.newQueue(spec);
}
return new Object[] {spec, q};
}
public static Matcher<Collection<?>> emptyAndZeroSize() {
return allOf(hasSize(0), empty());
}
}