io.reactivex.internal.operators.observable.ObservableGroupBy Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of rxjava Show documentation
Show all versions of rxjava Show documentation
Reactive Extensions for Java
/**
* Copyright (c) 2016-present, RxJava Contributors.
*
* 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 io.reactivex.internal.operators.observable;
import io.reactivex.internal.functions.ObjectHelper;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.*;
import io.reactivex.ObservableSource;
import io.reactivex.Observer;
import io.reactivex.disposables.Disposable;
import io.reactivex.exceptions.Exceptions;
import io.reactivex.functions.Function;
import io.reactivex.internal.disposables.*;
import io.reactivex.internal.queue.SpscLinkedArrayQueue;
import io.reactivex.observables.GroupedObservable;
public final class ObservableGroupBy extends AbstractObservableWithUpstream> {
final Function keySelector;
final Function valueSelector;
final int bufferSize;
final boolean delayError;
public ObservableGroupBy(ObservableSource source,
Function keySelector, Function valueSelector,
int bufferSize, boolean delayError) {
super(source);
this.keySelector = keySelector;
this.valueSelector = valueSelector;
this.bufferSize = bufferSize;
this.delayError = delayError;
}
@Override
public void subscribeActual(Observer> t) {
source.subscribe(new GroupByObserver(t, keySelector, valueSelector, bufferSize, delayError));
}
public static final class GroupByObserver extends AtomicInteger implements Observer, Disposable {
private static final long serialVersionUID = -3688291656102519502L;
final Observer> downstream;
final Function keySelector;
final Function valueSelector;
final int bufferSize;
final boolean delayError;
final Map> groups;
static final Object NULL_KEY = new Object();
Disposable upstream;
final AtomicBoolean cancelled = new AtomicBoolean();
public GroupByObserver(Observer> actual, Function keySelector, Function valueSelector, int bufferSize, boolean delayError) {
this.downstream = actual;
this.keySelector = keySelector;
this.valueSelector = valueSelector;
this.bufferSize = bufferSize;
this.delayError = delayError;
this.groups = new ConcurrentHashMap>();
this.lazySet(1);
}
@Override
public void onSubscribe(Disposable d) {
if (DisposableHelper.validate(this.upstream, d)) {
this.upstream = d;
downstream.onSubscribe(this);
}
}
@Override
public void onNext(T t) {
K key;
try {
key = keySelector.apply(t);
} catch (Throwable e) {
Exceptions.throwIfFatal(e);
upstream.dispose();
onError(e);
return;
}
Object mapKey = key != null ? key : NULL_KEY;
GroupedUnicast group = groups.get(mapKey);
if (group == null) {
// if the main has been cancelled, stop creating groups
// and skip this value
if (cancelled.get()) {
return;
}
group = GroupedUnicast.createWith(key, bufferSize, this, delayError);
groups.put(mapKey, group);
getAndIncrement();
downstream.onNext(group);
}
V v;
try {
v = ObjectHelper.requireNonNull(valueSelector.apply(t), "The value supplied is null");
} catch (Throwable e) {
Exceptions.throwIfFatal(e);
upstream.dispose();
onError(e);
return;
}
group.onNext(v);
}
@Override
public void onError(Throwable t) {
List> list = new ArrayList>(groups.values());
groups.clear();
for (GroupedUnicast e : list) {
e.onError(t);
}
downstream.onError(t);
}
@Override
public void onComplete() {
List> list = new ArrayList>(groups.values());
groups.clear();
for (GroupedUnicast e : list) {
e.onComplete();
}
downstream.onComplete();
}
@Override
public void dispose() {
// cancelling the main source means we don't want any more groups
// but running groups still require new values
if (cancelled.compareAndSet(false, true)) {
if (decrementAndGet() == 0) {
upstream.dispose();
}
}
}
@Override
public boolean isDisposed() {
return cancelled.get();
}
public void cancel(K key) {
Object mapKey = key != null ? key : NULL_KEY;
groups.remove(mapKey);
if (decrementAndGet() == 0) {
upstream.dispose();
}
}
}
static final class GroupedUnicast extends GroupedObservable {
final State state;
public static GroupedUnicast createWith(K key, int bufferSize, GroupByObserver parent, boolean delayError) {
State state = new State(bufferSize, parent, key, delayError);
return new GroupedUnicast(key, state);
}
protected GroupedUnicast(K key, State state) {
super(key);
this.state = state;
}
@Override
protected void subscribeActual(Observer observer) {
state.subscribe(observer);
}
public void onNext(T t) {
state.onNext(t);
}
public void onError(Throwable e) {
state.onError(e);
}
public void onComplete() {
state.onComplete();
}
}
static final class State extends AtomicInteger implements Disposable, ObservableSource {
private static final long serialVersionUID = -3852313036005250360L;
final K key;
final SpscLinkedArrayQueue queue;
final GroupByObserver parent;
final boolean delayError;
volatile boolean done;
Throwable error;
final AtomicBoolean cancelled = new AtomicBoolean();
final AtomicBoolean once = new AtomicBoolean();
final AtomicReference> actual = new AtomicReference>();
State(int bufferSize, GroupByObserver parent, K key, boolean delayError) {
this.queue = new SpscLinkedArrayQueue(bufferSize);
this.parent = parent;
this.key = key;
this.delayError = delayError;
}
@Override
public void dispose() {
if (cancelled.compareAndSet(false, true)) {
if (getAndIncrement() == 0) {
actual.lazySet(null);
parent.cancel(key);
}
}
}
@Override
public boolean isDisposed() {
return cancelled.get();
}
@Override
public void subscribe(Observer observer) {
if (once.compareAndSet(false, true)) {
observer.onSubscribe(this);
actual.lazySet(observer);
if (cancelled.get()) {
actual.lazySet(null);
} else {
drain();
}
} else {
EmptyDisposable.error(new IllegalStateException("Only one Observer allowed!"), observer);
}
}
public void onNext(T t) {
queue.offer(t);
drain();
}
public void onError(Throwable e) {
error = e;
done = true;
drain();
}
public void onComplete() {
done = true;
drain();
}
void drain() {
if (getAndIncrement() != 0) {
return;
}
int missed = 1;
final SpscLinkedArrayQueue q = queue;
final boolean delayError = this.delayError;
Observer a = actual.get();
for (;;) {
if (a != null) {
for (;;) {
boolean d = done;
T v = q.poll();
boolean empty = v == null;
if (checkTerminated(d, empty, a, delayError)) {
return;
}
if (empty) {
break;
}
a.onNext(v);
}
}
missed = addAndGet(-missed);
if (missed == 0) {
break;
}
if (a == null) {
a = actual.get();
}
}
}
boolean checkTerminated(boolean d, boolean empty, Observer a, boolean delayError) {
if (cancelled.get()) {
queue.clear();
parent.cancel(key);
actual.lazySet(null);
return true;
}
if (d) {
if (delayError) {
if (empty) {
Throwable e = error;
actual.lazySet(null);
if (e != null) {
a.onError(e);
} else {
a.onComplete();
}
return true;
}
} else {
Throwable e = error;
if (e != null) {
queue.clear();
actual.lazySet(null);
a.onError(e);
return true;
} else
if (empty) {
actual.lazySet(null);
a.onComplete();
return true;
}
}
}
return false;
}
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy