/*
* Copyright 2014 the original author or 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 ratpack.rx.internal;
import com.google.common.collect.MapMaker;
import ratpack.exec.ExecController;
import rx.Scheduler;
import rx.schedulers.Schedulers;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.atomic.AtomicReference;
public class MultiExecControllerBackedScheduler extends Scheduler {
private final ConcurrentMap<ExecController, Scheduler> map = new MapMaker().weakKeys().weakValues().makeMap();
private final AtomicReference<Scheduler> fallback = new AtomicReference<>();
private Scheduler getDelegateScheduler() {
return ExecController.current()
.map(c -> map.computeIfAbsent(c, ExecControllerBackedScheduler::new))
.orElseGet(() -> {
if (fallback.get() == null) {
int nThreads = Runtime.getRuntime().availableProcessors();
ExecutorService executor = Executors.newFixedThreadPool(nThreads);
Scheduler scheduler = Schedulers.from(executor);
fallback.compareAndSet(null, scheduler);
}
return fallback.get();
});
}
@Override
public Worker createWorker() {
return getDelegateScheduler().createWorker();
}
@Override
public int parallelism() {
return getDelegateScheduler().parallelism();
}
@Override
public long now() {
return getDelegateScheduler().now();
}
}