/*
* 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.function.Predicate;
import org.reactivestreams.Subscriber;
import org.reactivestreams.Subscription;
import reactor.core.Fuseable;
/**
* Filters out values that make a filter function return false.
*
* @param <T> the value type
*
* @see <a href="https://github.com/reactor/reactive-streams-commons">Reactive-Streams-Commons</a>
*/
final class FluxFilterFuseable<T> extends FluxSource<T, T> implements Fuseable {
final Predicate<? super T> predicate;
FluxFilterFuseable(Flux<? extends T> source, Predicate<? super T> predicate) {
super(source);
this.predicate = Objects.requireNonNull(predicate, "predicate");
}
@Override
@SuppressWarnings("unchecked")
public void subscribe(Subscriber<? super T> s) {
if (s instanceof ConditionalSubscriber) {
source.subscribe(new FilterFuseableConditionalSubscriber<>((ConditionalSubscriber<? super T>) s,
predicate));
return;
}
source.subscribe(new FilterFuseableSubscriber<>(s, predicate));
}
static final class FilterFuseableSubscriber<T>
implements InnerOperator<T, T>, QueueSubscription<T>,
ConditionalSubscriber<T> {
final Subscriber<? super T> actual;
final Predicate<? super T> predicate;
QueueSubscription<T> s;
boolean done;
int sourceMode;
FilterFuseableSubscriber(Subscriber<? super T> actual,
Predicate<? super T> predicate) {
this.actual = actual;
this.predicate = predicate;
}
@SuppressWarnings("unchecked")
@Override
public void onSubscribe(Subscription s) {
if (Operators.validate(this.s, s)) {
this.s = (QueueSubscription<T>) s;
actual.onSubscribe(this);
}
}
@Override
public void onNext(T t) {
if (sourceMode == ASYNC) {
actual.onNext(null);
}
else {
if (done) {
Operators.onNextDropped(t);
return;
}
boolean b;
try {
b = predicate.test(t);
}
catch (Throwable e) {
onError(Operators.onOperatorError(s, e, t));
return;
}
if (b) {
actual.onNext(t);
}
else {
s.request(1);
}
}
}
@Override
public boolean tryOnNext(T t) {
if (done) {
Operators.onNextDropped(t);
return false;
}
boolean b;
try {
b = predicate.test(t);
}
catch (Throwable e) {
onError(Operators.onOperatorError(s, e, t));
return false;
}
if (b) {
actual.onNext(t);
return true;
}
return false;
}
@Override
public void onError(Throwable t) {
if (done) {
Operators.onErrorDropped(t);
return;
}
done = true;
actual.onError(t);
}
@Override
public void onComplete() {
if (done) {
return;
}
done = true;
actual.onComplete();
}
@Override
public Object scan(Attr key) {
switch (key) {
case PARENT:
return s;
case TERMINATED:
return done;
}
return InnerOperator.super.scan(key);
}
@Override
public Subscriber<? super T> actual() {
return actual;
}
@Override
public void request(long n) {
s.request(n);
}
@Override
public void cancel() {
s.cancel();
}
@Override
public T poll() {
if (sourceMode == ASYNC) {
long dropped = 0;
for (; ; ) {
T v = s.poll();
if (v == null || predicate.test(v)) {
if (dropped != 0) {
request(dropped);
}
return v;
}
dropped++;
}
}
else {
for (; ; ) {
T v = s.poll();
if (v == null || predicate.test(v)) {
return v;
}
}
}
}
@Override
public boolean isEmpty() {
return s.isEmpty();
}
@Override
public void clear() {
s.clear();
}
@Override
public int requestFusion(int requestedMode) {
int m;
if ((requestedMode & Fuseable.THREAD_BARRIER) != 0) {
return Fuseable.NONE;
}
else {
m = s.requestFusion(requestedMode);
}
sourceMode = m;
return m;
}
@Override
public int size() {
return s.size();
}
}
static final class FilterFuseableConditionalSubscriber<T>
implements InnerOperator<T, T>, ConditionalSubscriber<T>,
QueueSubscription<T> {
final ConditionalSubscriber<? super T> actual;
final Predicate<? super T> predicate;
QueueSubscription<T> s;
boolean done;
int sourceMode;
FilterFuseableConditionalSubscriber(ConditionalSubscriber<? super T> actual,
Predicate<? super T> predicate) {
this.actual = actual;
this.predicate = predicate;
}
@SuppressWarnings("unchecked")
@Override
public void onSubscribe(Subscription s) {
if (Operators.validate(this.s, s)) {
this.s = (QueueSubscription<T>) s;
actual.onSubscribe(this);
}
}
@Override
public void onNext(T t) {
if (sourceMode == ASYNC) {
actual.onNext(null);
}
else {
if (done) {
Operators.onNextDropped(t);
return;
}
boolean b;
try {
b = predicate.test(t);
}
catch (Throwable e) {
onError(Operators.onOperatorError(s, e, t));
return;
}
if (b) {
actual.onNext(t);
}
else {
s.request(1);
}
}
}
@Override
public boolean tryOnNext(T t) {
if (done) {
Operators.onNextDropped(t);
return false;
}
boolean b;
try {
b = predicate.test(t);
}
catch (Throwable e) {
onError(Operators.onOperatorError(s, e, t));
return false;
}
return b && actual.tryOnNext(t);
}
@Override
public void onError(Throwable t) {
if (done) {
Operators.onErrorDropped(t);
return;
}
done = true;
actual.onError(t);
}
@Override
public void onComplete() {
if (done) {
return;
}
done = true;
actual.onComplete();
}
@Override
public Object scan(Attr key) {
switch (key) {
case PARENT:
return s;
case TERMINATED:
return done;
}
return InnerOperator.super.scan(key);
}
@Override
public Subscriber<? super T> actual() {
return actual;
}
@Override
public void request(long n) {
s.request(n);
}
@Override
public void cancel() {
s.cancel();
}
@Override
public T poll() {
if (sourceMode == ASYNC) {
long dropped = 0;
for (; ; ) {
T v = s.poll();
if (v == null || predicate.test(v)) {
if (dropped != 0) {
request(dropped);
}
return v;
}
dropped++;
}
}
else {
for (; ; ) {
T v = s.poll();
if (v == null || predicate.test(v)) {
return v;
}
}
}
}
@Override
public boolean isEmpty() {
return s.isEmpty();
}
@Override
public void clear() {
s.clear();
}
@Override
public int size() {
return s.size();
}
@Override
public int requestFusion(int requestedMode) {
int m;
if ((requestedMode & Fuseable.THREAD_BARRIER) != 0) {
return Fuseable.NONE;
}
else {
m = s.requestFusion(requestedMode);
}
sourceMode = m;
return m;
}
}
}