/*
 * Copyright (c) 2011-2017 Pivotal Software 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
 *
 *       https://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 reactor.core.publisher;

import java.util.concurrent.TimeUnit;

import org.reactivestreams.Subscription;
import reactor.core.CoreSubscriber;
import reactor.core.Fuseable;
import reactor.core.scheduler.Scheduler;
import reactor.util.annotation.Nullable;
import reactor.util.function.Tuple2;
import reactor.util.function.Tuples;

Author:Stephane Maldini
/** * @author Stephane Maldini */
final class FluxElapsed<T> extends InternalFluxOperator<T, Tuple2<Long, T>> implements Fuseable { final Scheduler scheduler; FluxElapsed(Flux<T> source, Scheduler scheduler) { super(source); this.scheduler = scheduler; } @Override public CoreSubscriber<? super T> subscribeOrReturn(CoreSubscriber<? super Tuple2<Long, T>> actual) { return new ElapsedSubscriber<>(actual, scheduler); } @Override public Object scanUnsafe(Attr key) { if (key == Attr.RUN_ON) return scheduler; if (key == Attr.RUN_STYLE) return Attr.RunStyle.SYNC; return super.scanUnsafe(key); } static final class ElapsedSubscriber<T> implements InnerOperator<T, Tuple2<Long, T>>, QueueSubscription<Tuple2<Long, T>> { final CoreSubscriber<? super Tuple2<Long, T>> actual; final Scheduler scheduler; Subscription s; QueueSubscription<T> qs; long lastTime; ElapsedSubscriber(CoreSubscriber<? super Tuple2<Long, T>> actual, Scheduler scheduler) { this.actual = actual; this.scheduler = scheduler; } @Override @Nullable public Object scanUnsafe(Attr key) { if (key == Attr.PARENT) return s; if (key == Attr.RUN_ON) return scheduler; if (key == Attr.RUN_STYLE) return Attr.RunStyle.SYNC; return InnerOperator.super.scanUnsafe(key); } @Override public void onSubscribe(Subscription s) { if (Operators.validate(this.s, s)) { lastTime = scheduler.now(TimeUnit.MILLISECONDS); this.s = s; actual.onSubscribe(this); } } @Override public CoreSubscriber<? super Tuple2<Long, T>> actual() { return actual; } @Override public void onNext(T t) { if(t == null){ actual.onNext(null); return; } actual.onNext(snapshot(t)); } @Override public void onError(Throwable t) { actual.onError(t); } @Override public void onComplete() { actual.onComplete(); } @Override public void request(long n) { s.request(n); } @Override public void cancel() { s.cancel(); } @Override public int requestFusion(int requestedMode) { QueueSubscription<T> qs = Operators.as(s); if (qs != null) { this.qs = qs; return qs.requestFusion(requestedMode); } return Fuseable.NONE; } Tuple2<Long, T> snapshot(T data){ long now = scheduler.now(TimeUnit.MILLISECONDS); long last = lastTime; lastTime = now; long delta = now - last; return Tuples.of(delta, data); } @Override @Nullable public Tuple2<Long, T> poll() { T data = qs.poll(); if(data != null){ return snapshot(data); } return null; } @Override public int size() { return qs.size(); } @Override public boolean isEmpty() { return qs.isEmpty(); } @Override public void clear() { qs.clear(); } } }