/**
* Copyright 2014 Netflix, Inc.
*
* 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 rx.schedulers;
import static org.junit.Assert.*;
import java.util.*;
import java.util.concurrent.TimeUnit;
import org.junit.Test;
import rx.*;
import rx.Observer;
import rx.Scheduler.Worker;
import rx.Observable;
import rx.functions.*;
import rx.observers.Observers;
import rx.observers.TestSubscriber;
import rx.subscriptions.CompositeSubscription;
public class TrampolineSchedulerTest extends AbstractSchedulerTests {
@Override
protected Scheduler getScheduler() {
return Schedulers.trampoline();
}
@Test
public final void testMergeWithCurrentThreadScheduler1() {
final String currentThreadName = Thread.currentThread().getName();
Observable<Integer> o1 = Observable.<Integer> just(1, 2, 3, 4, 5);
Observable<Integer> o2 = Observable.<Integer> just(6, 7, 8, 9, 10);
Observable<String> o = Observable.<Integer> merge(o1, o2).subscribeOn(Schedulers.trampoline()).map(new Func1<Integer, String>() {
@Override
public String call(Integer t) {
assertTrue(Thread.currentThread().getName().equals(currentThreadName));
return "Value_" + t + "_Thread_" + Thread.currentThread().getName();
}
});
o.toBlocking().forEach(new Action1<String>() {
@Override
public void call(String t) {
System.out.println("t: " + t);
}
});
}
@Test
public void testNestedTrampolineWithUnsubscribe() {
final ArrayList<String> workDone = new ArrayList<String>();
final CompositeSubscription workers = new CompositeSubscription();
Worker worker = Schedulers.trampoline().createWorker();
try {
workers.add(worker);
worker.schedule(new Action0() {
@Override
public void call() {
workers.add(doWorkOnNewTrampoline("A", workDone));
}
});
final Worker worker2 = Schedulers.trampoline().createWorker();
workers.add(worker2);
worker2.schedule(new Action0() {
@Override
public void call() {
workers.add(doWorkOnNewTrampoline("B", workDone));
// we unsubscribe worker2 ... it should not affect work scheduled on a separate Trampline.Worker
worker2.unsubscribe();
}
});
assertEquals(6, workDone.size());
assertEquals(Arrays.asList("A.1", "A.B.1", "A.B.2", "B.1", "B.B.1", "B.B.2"), workDone);
} finally {
workers.unsubscribe();
}
}
/**
* This is a regression test for #1702. Concurrent work scheduling that is improperly synchronized can cause an
* action to be added or removed onto the priority queue during a poll, which can result in NPEs during queue
* sifting. While it is difficult to isolate the issue directly, we can easily trigger the behavior by spamming the
* trampoline with enqueue requests from multiple threads concurrently.
*/
@Test
public void testTrampolineWorkerHandlesConcurrentScheduling() {
final Worker trampolineWorker = Schedulers.trampoline().createWorker();
final Observer<Subscription> observer = Observers.empty();
final TestSubscriber<Subscription> ts = new TestSubscriber<Subscription>(observer);
// Spam the trampoline with actions.
Observable.range(0, 50)
.flatMap(new Func1<Integer, Observable<Subscription>>() {
@Override
public Observable<Subscription> call(Integer count) {
return Observable.interval(1, TimeUnit.MICROSECONDS).map(
new Func1<Long, Subscription>() {
@Override
public Subscription call(Long count) {
return trampolineWorker.schedule(new Action0() {
@Override
public void call() {}
});
}
}).limit(100);
}
})
.subscribeOn(Schedulers.computation())
.subscribe(ts);
ts.awaitTerminalEvent();
ts.assertNoErrors();
}
private static Worker doWorkOnNewTrampoline(final String key, final ArrayList<String> workDone) {
Worker worker = Schedulers.trampoline().createWorker();
worker.schedule(new Action0() {
@Override
public void call() {
String msg = key + ".1";
workDone.add(msg);
System.out.println(msg);
Worker worker3 = Schedulers.trampoline().createWorker();
worker3.schedule(createPrintAction(key + ".B.1", workDone));
worker3.schedule(createPrintAction(key + ".B.2", workDone));
}
});
return worker;
}
private static Action0 createPrintAction(final String message, final ArrayList<String> workDone) {
return new Action0() {
@Override
public void call() {
System.out.println(message);
workDone.add(message);
}
};
}
}