@Test(timeout = 10000)
public void shutdownShouldNotLeadToThreadInitialization() throws InterruptedException {
DaemonThreadFactory factory = new DaemonThreadFactory("42");
util.setThreadFactory(factory);
util.shutdownBackgroundExecutor();
assertEquals(0, factory.getCreatedThreads());
}
@Test(timeout = 10000)
public void shouldCorrectlyStopBackgroundExecutor() throws InterruptedException {
CountDownLatch latch = new CountDownLatch(1);
Thread[] executorThread = new Thread[1];
Runnable task =
() -> {
executorThread[0] = Thread.currentThread();
latch.countDown();
};
Executor executor = util.getBackgroundExecutor();
util.execute(executor, task);
latch.await();
util.shutdownBackgroundExecutor();
executorThread[0].join();
}
@Test(timeout = 10000)
public void shouldApplyThreadFactory() throws InterruptedException {
ThreadFactory factory = new DaemonThreadFactory("42");
util.setThreadFactory(factory);
Executor executor = util.getBackgroundExecutor();
CountDownLatch latch = new CountDownLatch(1);
AtomicReference<String> threadName = new AtomicReference<>();
executor.execute(
() -> {
threadName.set(Thread.currentThread().getName());
latch.countDown();
});
latch.await();
assertEquals("42", threadName.get());
}
@Test(timeout = 10000)
public void shouldExecuteTaskInCurrentThreadWhenExecutorThrowException()
throws InterruptedException {
CountDownLatch latch = new CountDownLatch(1);
Executor executor =
task -> {
throw new RejectedExecutionException();
};
Runnable task = latch::countDown;
util.execute(executor, task);
latch.await();
}
@Test(timeout = 10000)
public void shouldExecuteTaskInCurrentThreadExactlyOnceWhenExecutorThrowException()
throws InterruptedException {
CountDownLatch latch = new CountDownLatch(1);
AtomicInteger executionCount = new AtomicInteger();
Executor executor =
task -> {
task.run();
throw new RejectedExecutionException();
};
Runnable task =
() -> {
executionCount.incrementAndGet();
latch.countDown();
};
util.execute(executor, task);
latch.await();
assertEquals(1, executionCount.get());
}
@Test(timeout = 10000)
public void shouldAlwaysReturnSameInstanceOfBackgroundExecutor() throws InterruptedException {
assertSame(util.getBackgroundExecutor(), util.getBackgroundExecutor());
}
@Test(expected = IllegalStateException.class)
public void shouldDisallowReplaceThreadFactoryWhenExecutorAlreadyCreated() {
util.getBackgroundExecutor();
util.setThreadFactory(new DaemonThreadFactory(""));
}
