reactor.core.publisher.MonoHasElements Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of redisson-all Show documentation

Easy Redis Java client and Real-Time Data Platform. Valkey compatible. Sync/Async/RxJava3/Reactive API. Client side caching. Over 50 Redis based Java objects and services: JCache API, Apache Tomcat, Hibernate, Spring, Set, Multimap, SortedSet, Map, List, Queue, Deque, Semaphore, Lock, AtomicLong, Map Reduce, Bloom filter, Scheduler, RPC

The newest version!

/*
 * Copyright (c) 2016-2022 VMware Inc. or its affiliates, 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 reactor.core.CoreSubscriber;
import reactor.core.Fuseable;
import reactor.util.annotation.Nullable;

/**
 * @see Reactive-Streams-Commons
 */
final class MonoHasElements extends MonoFromFluxOperator
		implements Fuseable {

	MonoHasElements(Flux source) {
		super(source);
	}

	@Override
	public CoreSubscriber subscribeOrReturn(CoreSubscriber actual) {
		return new HasElementsSubscriber<>(actual);
	}

	@Override
	public Object scanUnsafe(Attr key) {
		if (key == Attr.RUN_STYLE) return Attr.RunStyle.SYNC;
		return super.scanUnsafe(key);
	}

	static final class HasElementsSubscriber extends Operators.BaseFluxToMonoOperator {

		boolean done;

		HasElementsSubscriber(CoreSubscriber actual) {
			super(actual);
		}

		@Override
		@Nullable
		public Object scanUnsafe(Attr key) {
			if (key == Attr.TERMINATED) return done;

			return super.scanUnsafe(key);
		}

		@Override
		public void onNext(T t) {
			Operators.onDiscard(t, currentContext());

			if (!done) {
				s.cancel();

				this.done = true;

				this.actual.onNext(true);
				this.actual.onComplete();
			}
		}

		@Override
		public void onError(Throwable t) {
			if (done) {
				Operators.onErrorDropped(t, currentContext());
				return;
			}

			this.actual.onError(t);
		}

		@Override
		public void onComplete() {
			if (done) {
				return;
			}

			this.done = true;

			completePossiblyEmpty();
		}

		@Override
		Boolean accumulatedValue() {
			return false;
		}
	}
}