/*
* 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.
Objects;
import java.util.concurrent.atomic.
AtomicIntegerFieldUpdater;
import java.util.concurrent.atomic.
AtomicReferenceFieldUpdater;
import org.reactivestreams.
Publisher;
import reactor.core.
CoreSubscriber;
import reactor.core.
Exceptions;
import reactor.util.annotation.
Nullable;
/**
* Concatenates a fixed array of Publishers' values.
*
* @param <T> the value type
* @see <a href="https://github.com/reactor/reactive-streams-commons">Reactive-Streams-Commons</a>
*/
final class
FluxConcatArray<T> extends
Flux<T> implements
SourceProducer<T> {
final
Publisher<? extends T>[]
array;
final boolean
delayError;
@
SafeVarargs
FluxConcatArray(boolean
delayError,
Publisher<? extends T>...
array) {
this.
array =
Objects.
requireNonNull(
array, "array");
this.
delayError =
delayError;
}
@
Override
public void
subscribe(
CoreSubscriber<? super T>
actual) {
Publisher<? extends T>[]
a =
array;
if (
a.length == 0) {
Operators.
complete(
actual);
return;
}
if (
a.length == 1) {
Publisher<? extends T>
p =
a[0];
if (
p == null) {
Operators.
error(
actual, new
NullPointerException("The single source Publisher is null"));
} else {
p.
subscribe(
actual);
}
return;
}
if (
delayError) {
ConcatArrayDelayErrorSubscriber<T>
parent = new
ConcatArrayDelayErrorSubscriber<>(
actual,
a);
actual.
onSubscribe(
parent);
if (!
parent.
isCancelled()) {
parent.
onComplete();
}
return;
}
ConcatArraySubscriber<T>
parent = new
ConcatArraySubscriber<>(
actual,
a);
actual.
onSubscribe(
parent);
if (!
parent.
isCancelled()) {
parent.
onComplete();
}
}
@
Override
public
Object scanUnsafe(
Attr key) {
if (
key ==
Attr.
DELAY_ERROR) return
delayError;
return null;
}
/**
* Returns a new instance which has the additional source to be merged together with
* the current array of sources.
* <p>
* This operation doesn't change the current FluxMerge instance.
*
* @param source the new source to merge with the others
* @return the new FluxConcatArray instance
*/
FluxConcatArray<T>
concatAdditionalSourceLast(
Publisher<? extends T>
source) {
int
n =
array.length;
@
SuppressWarnings("unchecked")
Publisher<? extends T>[]
newArray = new
Publisher[
n + 1];
System.
arraycopy(
array, 0,
newArray, 0,
n);
newArray[
n] =
source;
return new
FluxConcatArray<>(
delayError,
newArray);
}
/**
* Returns a new instance which has the additional source to be merged together with
* the current array of sources.
* <p>
* This operation doesn't change the current FluxMerge instance.
*
* @param source the new source to merge with the others
* @return the new FluxConcatArray instance
*/
@
SuppressWarnings("unchecked")
<V>
FluxConcatArray<V>
concatAdditionalIgnoredLast(
Publisher<? extends V>
source) {
int
n =
array.length;
Publisher<? extends V>[]
newArray = new
Publisher[
n + 1];
//noinspection SuspiciousSystemArraycopy
System.
arraycopy(
array, 0,
newArray, 0,
n);
newArray[
n - 1] =
Mono.
ignoreElements(
newArray[
n - 1]);
newArray[
n] =
source;
return new
FluxConcatArray<>(
delayError,
newArray);
}
/**
* Returns a new instance which has the additional first source to be concatenated together with
* the current array of sources.
* <p>
* This operation doesn't change the current FluxConcatArray instance.
*
* @param source the new source to merge with the others
* @return the new FluxConcatArray instance
*/
FluxConcatArray<T>
concatAdditionalSourceFirst(
Publisher<? extends T>
source) {
int
n =
array.length;
@
SuppressWarnings("unchecked")
Publisher<? extends T>[]
newArray = new
Publisher[
n + 1];
System.
arraycopy(
array, 0,
newArray, 1,
n);
newArray[0] =
source;
return new
FluxConcatArray<>(
delayError,
newArray);
}
static final class
ConcatArraySubscriber<T>
extends
Operators.
MultiSubscriptionSubscriber<T, T> {
final
Publisher<? extends T>[]
sources;
int
index;
volatile int
wip;
@
SuppressWarnings("rawtypes")
static final
AtomicIntegerFieldUpdater<
ConcatArraySubscriber>
WIP =
AtomicIntegerFieldUpdater.
newUpdater(
ConcatArraySubscriber.class, "wip");
long
produced;
ConcatArraySubscriber(
CoreSubscriber<? super T>
actual,
Publisher<? extends T>[]
sources) {
super(
actual);
this.
sources =
sources;
}
@
Override
public void
onNext(T
t) {
produced++;
actual.
onNext(
t);
}
@
Override
public void
onComplete() {
if (
WIP.
getAndIncrement(this) == 0) {
Publisher<? extends T>[]
a =
sources;
do {
if (
isCancelled()) {
return;
}
int
i =
index;
if (
i ==
a.length) {
actual.
onComplete();
return;
}
Publisher<? extends T>
p =
a[
i];
if (
p == null) {
actual.
onError(new
NullPointerException("Source Publisher at index " +
i + " is null"));
return;
}
long
c =
produced;
if (
c != 0L) {
produced = 0L;
produced(
c);
}
p.
subscribe(this);
if (
isCancelled()) {
return;
}
index = ++
i;
} while (
WIP.
decrementAndGet(this) != 0);
}
}
}
static final class
ConcatArrayDelayErrorSubscriber<T>
extends
Operators.
MultiSubscriptionSubscriber<T, T> {
final
Publisher<? extends T>[]
sources;
int
index;
volatile int
wip;
@
SuppressWarnings("rawtypes")
static final
AtomicIntegerFieldUpdater<
ConcatArrayDelayErrorSubscriber>
WIP =
AtomicIntegerFieldUpdater.
newUpdater(
ConcatArrayDelayErrorSubscriber.class, "wip");
volatile
Throwable error;
@
SuppressWarnings("rawtypes")
static final
AtomicReferenceFieldUpdater<
ConcatArrayDelayErrorSubscriber,
Throwable>
ERROR =
AtomicReferenceFieldUpdater.
newUpdater(
ConcatArrayDelayErrorSubscriber.class,
Throwable.class, "error");
long
produced;
ConcatArrayDelayErrorSubscriber(
CoreSubscriber<? super T>
actual,
Publisher<?
extends T>[]
sources) {
super(
actual);
this.
sources =
sources;
}
@
Override
public void
onNext(T
t) {
produced++;
actual.
onNext(
t);
}
@
Override
public void
onError(
Throwable t) {
if (
Exceptions.
addThrowable(
ERROR, this,
t)) {
onComplete();
} else {
Operators.
onErrorDropped(
t,
actual.
currentContext());
}
}
@
Override
@
Nullable
public
Object scanUnsafe(
Attr key) {
if (
key ==
Attr.
DELAY_ERROR) return true;
if (
key ==
Attr.
ERROR) return
error;
return super.scanUnsafe(
key);
}
@
Override
public void
onComplete() {
if (
WIP.
getAndIncrement(this) == 0) {
Publisher<? extends T>[]
a =
sources;
do {
if (
isCancelled()) {
return;
}
int
i =
index;
if (
i ==
a.length) {
Throwable e =
Exceptions.
terminate(
ERROR, this);
if (
e != null) {
actual.
onError(
e);
} else {
actual.
onComplete();
}
return;
}
Publisher<? extends T>
p =
a[
i];
if (
p == null) {
actual.
onError(new
NullPointerException("Source Publisher at index " +
i + " is null"));
return;
}
long
c =
produced;
if (
c != 0L) {
produced = 0L;
produced(
c);
}
p.
subscribe(this);
if (
isCancelled()) {
return;
}
index = ++
i;
} while (
WIP.
decrementAndGet(this) != 0);
}
}
}
}