/*
* 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
*
* 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 reactor.core.publisher;
import java.util.
AbstractQueue;
import java.util.
Iterator;
import java.util.concurrent.atomic.
AtomicLongFieldUpdater;
import java.util.function.
BooleanSupplier;
import org.reactivestreams.
Subscription;
import reactor.core.
CoreSubscriber;
import reactor.util.annotation.
Nullable;
/**
* @author Stephane Maldini
*/
final class
FluxDematerialize<T> extends
FluxOperator<
Signal<T>, T> {
FluxDematerialize(
Flux<
Signal<T>>
source) {
super(
source);
}
@
Override
public void
subscribe(
CoreSubscriber<? super T>
actual) {
source.
subscribe(new
DematerializeSubscriber<>(
actual));
}
static final class
DematerializeSubscriber<T> extends
AbstractQueue<T>
implements
InnerOperator<
Signal<T>, T>,
BooleanSupplier {
final
CoreSubscriber<? super T>
actual;
Subscription s;
T
value;
boolean
done;
long
produced;
volatile long
requested;
@
SuppressWarnings("rawtypes")
static final
AtomicLongFieldUpdater<
DematerializeSubscriber>
REQUESTED =
AtomicLongFieldUpdater.
newUpdater(
DematerializeSubscriber.class,
"requested");
volatile boolean
cancelled;
Throwable error;
DematerializeSubscriber(
CoreSubscriber<? super T>
subscriber) {
this.
actual =
subscriber;
}
@
Override
@
Nullable
public
Object scanUnsafe(
Attr key) {
if (
key ==
Attr.
PARENT) return
s;
if (
key ==
Attr.
TERMINATED) return
done;
if (
key ==
Attr.
REQUESTED_FROM_DOWNSTREAM) return
requested;
if (
key ==
Attr.
ERROR) return
error;
if (
key ==
Attr.
CANCELLED) return
cancelled;
if (
key ==
Attr.
BUFFERED) return
size();
return
InnerOperator.super.scanUnsafe(
key);
}
@
Override
public void
onSubscribe(
Subscription s) {
if (
Operators.
validate(this.
s,
s)) {
this.
s =
s;
actual.
onSubscribe(this);
s.
request(1);
}
}
@
Override
public void
onNext(
Signal<T>
t) {
if (
done) {
Operators.
onNextDropped(
t,
actual.
currentContext());
return;
}
if (
t.
isOnComplete()) {
s.
cancel();
onComplete();
}
else if (
t.
isOnError()) {
s.
cancel();
onError(
t.
getThrowable());
}
else if (
t.
isOnNext()) {
T
v =
value;
value =
t.
get();
if (
v != null) {
produced++;
actual.
onNext(
v);
}
}
}
@
Override
public void
onError(
Throwable t) {
if (
done) {
Operators.
onErrorDropped(
t,
actual.
currentContext());
return;
}
done = true;
error =
t;
long
p =
produced;
if (
p != 0L) {
Operators.
addCap(
REQUESTED, this, -
p);
}
DrainUtils.
postCompleteDelayError(
actual, this,
REQUESTED, this, this,
error);
}
@
Override
public void
onComplete() {
if (
done) {
return;
}
done = true;
long
p =
produced;
if (
p != 0L) {
Operators.
addCap(
REQUESTED, this, -
p);
}
DrainUtils.
postCompleteDelayError(
actual, this,
REQUESTED, this, this,
error);
}
@
Override
public void
request(long
n) {
if (
Operators.
validate(
n)) {
if (!
DrainUtils.
postCompleteRequestDelayError(
n,
actual,
this,
REQUESTED,
this,
this,
error)) {
s.
request(
n);
}
}
}
@
Override
public void
cancel() {
cancelled = true;
s.
cancel();
}
@
Override
public
CoreSubscriber<? super T>
actual() {
return
actual;
}
@
Override
public boolean
getAsBoolean() {
return
cancelled;
}
@
Override
public int
size() {
return
value == null ? 0 : 1;
}
@
Override
public boolean
isEmpty() {
return
value == null;
}
@
Override
public boolean
offer(T
e) {
throw new
UnsupportedOperationException();
}
@
Override
@
Nullable
public T
peek() {
return
value;
}
@
Override
@
Nullable
public T
poll() {
T
v =
value;
if (
v != null) {
value = null;
return
v;
}
return null;
}
@
Override
public
Iterator<T>
iterator() {
throw new
UnsupportedOperationException();
}
}
}