| // Copyright 2011 Google Inc. All Rights Reserved. |
| // |
| // 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.enterprise.adaptor; |
| |
| import static org.junit.Assert.*; |
| |
| import org.junit.Test; |
| |
| import java.util.concurrent.atomic.AtomicInteger; |
| |
| /** |
| * Test cases for {@link OneAtATimeRunnable}. |
| */ |
| public class OneAtATimeRunnableTest { |
| private MustInterruptRunnable mainRunnable = new MustInterruptRunnable(); |
| private CountingRunnable alreadyRunning = new CountingRunnable(); |
| private OneAtATimeRunnable runnable |
| = new OneAtATimeRunnable(mainRunnable, alreadyRunning); |
| |
| @Test(expected = NullPointerException.class) |
| public void testNullRunnable() { |
| new OneAtATimeRunnable(null, alreadyRunning); |
| } |
| |
| @Test(expected = NullPointerException.class) |
| public void testNullAlreadyRunningRunnable() { |
| new OneAtATimeRunnable(mainRunnable, null); |
| } |
| |
| @Test |
| public void testMultipleSimultaneosInvocations() throws Exception { |
| Thread thread1 = new Thread(runnable); |
| Thread thread2 = new Thread(runnable); |
| Thread thread3 = new Thread(runnable); |
| thread1.start(); |
| thread2.start(); |
| thread3.start(); |
| // We have to give all the threads enough time to get up and running. We |
| // can't use Thread.join() because we don't know which thread is going to |
| // run forever. This means either do this weird Thread.yield() trickery or |
| // hard-code a Thread.sleep() and cross our fingers. |
| while (mainRunnable.getCounter() != 1) { |
| Thread.yield(); |
| } |
| while (alreadyRunning.getCounter() != 2) { |
| Thread.yield(); |
| } |
| assertTrue(runnable.isRunning()); |
| thread1.interrupt(); |
| thread2.interrupt(); |
| thread3.interrupt(); |
| thread1.join(); |
| thread2.join(); |
| thread3.join(); |
| assertFalse(runnable.isRunning()); |
| assertEquals(1, mainRunnable.getCounter()); |
| assertEquals(2, alreadyRunning.getCounter()); |
| assertSame(mainRunnable, runnable.getRunnable()); |
| assertSame(alreadyRunning, runnable.getAlreadyRunningRunnable()); |
| |
| // Test to make sure later executions work as well. |
| thread1 = new Thread(runnable); |
| thread1.start(); |
| thread1.interrupt(); |
| thread1.join(); |
| assertEquals(2, mainRunnable.getCounter()); |
| assertEquals(2, alreadyRunning.getCounter()); |
| } |
| |
| /** Thread-safe. */ |
| private static class CountingRunnable implements Runnable { |
| private AtomicInteger counter = new AtomicInteger(); |
| |
| @Override |
| public void run() { |
| counter.incrementAndGet(); |
| } |
| |
| public int getCounter() { |
| return counter.get(); |
| } |
| } |
| |
| /** Thread-safe. */ |
| private static class MustInterruptRunnable extends CountingRunnable { |
| @Override |
| public void run() { |
| super.run(); |
| while (true) { |
| try { |
| Thread.sleep(100000); |
| } catch (InterruptedException ex) { |
| break; |
| } |
| } |
| } |
| } |
| } |