/*
* Copyright (C) 2008 The Guava Authors
*
* 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.google.common.testing;
import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import junit.framework.TestCase;
import java.util.concurrent.Callable;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
/**
* Unit test for {@link FakeTicker}.
*
* @author benyu@google.com (Jige Yu)
*/
@GwtCompatible(emulated = true)
public class FakeTickerTest extends TestCase {
public void testAdvance() {
FakeTicker ticker = new FakeTicker();
assertEquals(0, ticker.read());
assertSame(ticker, ticker.advance(10));
assertEquals(10, ticker.read());
ticker.advance(1, TimeUnit.MILLISECONDS);
assertEquals(1000010L, ticker.read());
}
@GwtIncompatible("concurrency")
public void testConcurrentAdvance() throws Exception {
final FakeTicker ticker = new FakeTicker();
int numberOfThreads = 64;
ExecutorService executorService = Executors.newFixedThreadPool(numberOfThreads);
final CountDownLatch startLatch = new CountDownLatch(numberOfThreads);
final CountDownLatch doneLatch = new CountDownLatch(numberOfThreads);
for (int i = numberOfThreads; i > 0; i--) {
executorService.submit(new Callable<Void>() {
@Override
public Void call() throws Exception {
// adds two nanoseconds to the ticker
startLatch.countDown();
startLatch.await();
ticker.advance(1L);
Thread.sleep(10);
ticker.advance(1L);
doneLatch.countDown();
return null;
}
});
}
doneLatch.await();
assertEquals(numberOfThreads * 2, ticker.read());
}
}