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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.commons.lang3.concurrent.locks;
import static org.junit.jupiter.api.Assertions.assertNotNull;
import static org.junit.jupiter.api.Assertions.assertNotSame;
import static org.junit.jupiter.api.Assertions.assertTrue;
import java.time.Duration;
import java.util.function.LongConsumer;
import org.apache.commons.lang3.AbstractLangTest;
import org.apache.commons.lang3.ArrayUtils;
import org.apache.commons.lang3.ThreadUtils;
import org.apache.commons.lang3.concurrent.locks.LockingVisitors.LockVisitor;
import org.apache.commons.lang3.concurrent.locks.LockingVisitors.StampedLockVisitor;
import org.apache.commons.lang3.function.FailableConsumer;
import org.junit.jupiter.api.Test;
public class LockingVisitorsTest extends AbstractLangTest {
private static final Duration SHORT_DELAY = Duration.ofMillis(100);
private static final Duration DELAY = Duration.ofMillis(1500);
private static final int NUMBER_OF_THREADS = 10;
private static final Duration TOTAL_DELAY = DELAY.multipliedBy(NUMBER_OF_THREADS);
protected boolean containsTrue(final boolean[] booleanArray) {
synchronized (booleanArray) {
return ArrayUtils.contains(booleanArray, true);
}
}
private void runTest(final Duration delay, final boolean exclusiveLock, final LongConsumer runTimeCheck,
final boolean[] booleanValues, final LockVisitor<boolean[], ?> visitor) throws InterruptedException {
final boolean[] runningValues = new boolean[10];
final long startTimeMillis = System.currentTimeMillis();
for (int i = 0; i < booleanValues.length; i++) {
final int index = i;
final FailableConsumer<boolean[], ?> consumer = b -> {
b[index] = false;
ThreadUtils.sleep(delay);
b[index] = true;
set(runningValues, index, false);
};
final Thread t = new Thread(() -> {
if (exclusiveLock) {
visitor.acceptWriteLocked(consumer);
} else {
visitor.acceptReadLocked(consumer);
}
});
set(runningValues, i, true);
t.start();
}
while (containsTrue(runningValues)) {
ThreadUtils.sleep(SHORT_DELAY);
}
final long endTimeMillis = System.currentTimeMillis();
for (final boolean booleanValue : booleanValues) {
assertTrue(booleanValue);
}
// WRONG assumption
// runTimeCheck.accept(endTimeMillis - startTimeMillis);
}
protected void set(final boolean[] booleanArray, final int offset, final boolean value) {
synchronized (booleanArray) {
booleanArray[offset] = value;
}
}
@Test
public void testReentrantReadWriteLockExclusive() throws Exception {
/*
* If our threads are running concurrently, then we expect to be no faster than running one after the other.
*/
final boolean[] booleanValues = new boolean[10];
runTest(DELAY, true, millis -> assertTrue(millis >= TOTAL_DELAY.toMillis()), booleanValues,
LockingVisitors.reentrantReadWriteLockVisitor(booleanValues));
}
@Test
public void testReentrantReadWriteLockNotExclusive() throws Exception {
/*
* If our threads are running concurrently, then we expect to be faster than running one after the other.
*/
final boolean[] booleanValues = new boolean[10];
runTest(DELAY, false, millis -> assertTrue(millis < TOTAL_DELAY.toMillis()), booleanValues,
LockingVisitors.reentrantReadWriteLockVisitor(booleanValues));
}
@Test
public void testResultValidation() {
final Object hidden = new Object();
final StampedLockVisitor<Object> lock = LockingVisitors.stampedLockVisitor(hidden);
final Object o1 = lock.applyReadLocked(h -> new Object());
assertNotNull(o1);
assertNotSame(hidden, o1);
final Object o2 = lock.applyWriteLocked(h -> new Object());
assertNotNull(o2);
assertNotSame(hidden, o2);
}
@Test
public void testStampedLockExclusive() throws Exception {
/*
* If our threads are running concurrently, then we expect to be no faster than running one after the other.
*/
final boolean[] booleanValues = new boolean[10];
runTest(DELAY, true, millis -> assertTrue(millis >= TOTAL_DELAY.toMillis()), booleanValues,
LockingVisitors.stampedLockVisitor(booleanValues));
}
@Test
public void testStampedLockNotExclusive() throws Exception {
/*
* If our threads are running concurrently, then we expect to be faster than running one after the other.
*/
final boolean[] booleanValues = new boolean[10];
runTest(DELAY, false, millis -> assertTrue(millis < TOTAL_DELAY.toMillis()), booleanValues,
LockingVisitors.stampedLockVisitor(booleanValues));
}
}
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