/*
* HA-JDBC: High-Availability JDBC
* Copyright (C) 2014 Paul Ferraro
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package net.sf.hajdbc.lock.semaphore;
import static org.junit.Assert.*;
import java.util.concurrent.Semaphore;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReadWriteLock;
import org.junit.Test;
public class SemaphoreReadWriteLockTest
{
@Test
public void test()
{
ReadWriteLock rwLock = new SemaphoreReadWriteLock(new Semaphore(2));
Lock readLock = rwLock.readLock();
Lock writeLock = rwLock.writeLock();
// Validate that a write lock blocks readers
assertTrue(writeLock.tryLock());
try
{
assertFalse(readLock.tryLock());
}
finally
{
writeLock.unlock();
}
assertTrue(readLock.tryLock());
try
{
// Validate that a read lock blocks writers
assertFalse(writeLock.tryLock());
// Validate multiple readers
assertTrue(readLock.tryLock());
try
{
// Validate max readers
assertFalse(readLock.tryLock());
}
finally
{
readLock.unlock();
}
}
finally
{
readLock.unlock();
}
}
}