/*
* 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.Objects;
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
import org.reactivestreams.Subscriber;
import reactor.core.CoreSubscriber;
import reactor.util.annotation.Nullable;
Emits a constant or generated Throwable instance to Subscribers.
Type parameters: - <T> – the value type
See Also:
/**
* Emits a constant or generated Throwable instance to Subscribers.
*
* @param <T> the value type
*
* @see <a href="https://github.com/reactor/reactive-streams-commons">Reactive-Streams-Commons</a>
*/
final class FluxErrorOnRequest<T> extends Flux<T> implements SourceProducer<T> {
final Throwable error;
FluxErrorOnRequest(Throwable error) {
this.error = Objects.requireNonNull(error);
}
@Override
public void subscribe(CoreSubscriber<? super T> actual) {
actual.onSubscribe(new ErrorSubscription(actual, error));
}
@Override
public Object scanUnsafe(Attr key) {
if (key == Attr.RUN_STYLE) return Attr.RunStyle.SYNC;
return null;
}
static final class ErrorSubscription implements InnerProducer {
final CoreSubscriber<?> actual;
final Throwable error;
volatile int once;
static final AtomicIntegerFieldUpdater<ErrorSubscription> ONCE =
AtomicIntegerFieldUpdater.newUpdater(ErrorSubscription.class, "once");
ErrorSubscription(CoreSubscriber<?> actual, Throwable error) {
this.actual = actual;
this.error = error;
}
@Override
public void request(long n) {
if (Operators.validate(n)) {
if (ONCE.compareAndSet(this, 0, 1)) {
actual.onError(error);
}
}
}
@Override
public void cancel() {
once = 1;
}
@Override
public CoreSubscriber actual() {
return actual;
}
@Override
@Nullable
public Object scanUnsafe(Attr key) {
if (key == Attr.ERROR) return error;
if (key == Attr.CANCELLED || key == Attr.TERMINATED)
return once == 1;
if (key == Attr.RUN_STYLE) return Attr.RunStyle.SYNC;
return InnerProducer.super.scanUnsafe(key);
}
}
}