/*
* 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.jena.shared;
import static com.jayway.awaitility.Awaitility.await;
import static java.lang.Thread.sleep;
import static java.util.concurrent.Executors.defaultThreadFactory;
import java.util.concurrent.atomic.AtomicBoolean;
import org.apache.jena.test.JenaTestBase;
import org.junit.Test;
import junit.framework.TestSuite;
public class TestLockMRPlusSW extends JenaTestBase {
public TestLockMRPlusSW(final String name) {
super(name);
}
public static TestSuite suite() {
return new TestSuite(TestLockMRPlusSW.class);
}
@Test
public void testMultipleReadersAtATime() {
final Lock testLock = new LockMRPlusSW();
testLock.enterCriticalSection(true);
final AtomicBoolean secondReaderHasLock = new AtomicBoolean();
// new reader
defaultThreadFactory().newThread(() -> {
testLock.enterCriticalSection(true);
secondReaderHasLock.set(true);
}).start();
// the only way to fail is to timeout
await().untilTrue(secondReaderHasLock);
}
@Test
public void testOneWriterAtATime() throws InterruptedException {
final Lock testLock = new LockMRPlusSW();
testLock.enterCriticalSection(false);
final AtomicBoolean secondWriterHasLock = new AtomicBoolean();
// new writer
defaultThreadFactory().newThread(() -> {
testLock.enterCriticalSection(false);
secondWriterHasLock.set(true);
}).start();
sleep(5000);
assertFalse("Multiple writers were allowed!", secondWriterHasLock.get());
}
@Test
public void testAWriterDoesNotBlockReaders() {
final Lock testLock = new LockMRPlusSW();
testLock.enterCriticalSection(false);
final AtomicBoolean readerHasLock = new AtomicBoolean();
// new reader
defaultThreadFactory().newThread(() -> {
testLock.enterCriticalSection(true);
readerHasLock.set(true);
}).start();
await().untilTrue(readerHasLock);
}
}