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.
/**
* 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.flowable;
import java.util.Iterator;
import org.reactivestreams.Subscriber;
import io.reactivex.Flowable;
import io.reactivex.annotations.Nullable;
import io.reactivex.exceptions.Exceptions;
import io.reactivex.internal.functions.ObjectHelper;
import io.reactivex.internal.fuseable.ConditionalSubscriber;
import io.reactivex.internal.subscriptions.*;
import io.reactivex.internal.util.BackpressureHelper;
public final class FlowableFromIterable<T> extends Flowable<T> {
final Iterable<? extends T> source;
public FlowableFromIterable(Iterable<? extends T> source) {
this.source = source;
}
@Override
public void subscribeActual(Subscriber<? super T> s) {
Iterator<? extends T> it;
try {
it = source.iterator();
} catch (Throwable e) {
Exceptions.throwIfFatal(e);
EmptySubscription.error(e, s);
return;
}
subscribe(s, it);
}
public static <T> void subscribe(Subscriber<? super T> s, Iterator<? extends T> it) {
boolean hasNext;
try {
hasNext = it.hasNext();
} catch (Throwable e) {
Exceptions.throwIfFatal(e);
EmptySubscription.error(e, s);
return;
}
if (!hasNext) {
EmptySubscription.complete(s);
return;
}
if (s instanceof ConditionalSubscriber) {
s.onSubscribe(new IteratorConditionalSubscription<T>(
(ConditionalSubscriber<? super T>)s, it));
} else {
s.onSubscribe(new IteratorSubscription<T>(s, it));
}
}
abstract static class BaseRangeSubscription<T> extends BasicQueueSubscription<T> {
private static final long serialVersionUID = -2252972430506210021L;
Iterator<? extends T> it;
volatile boolean cancelled;
boolean once;
BaseRangeSubscription(Iterator<? extends T> it) {
this.it = it;
}
@Override
public final int requestFusion(int mode) {
return mode & SYNC;
}
@Nullable
@Override
public final T poll() {
if (it == null) {
return null;
}
if (!once) {
once = true;
} else {
if (!it.hasNext()) {
return null;
}
}
return ObjectHelper.requireNonNull(it.next(), "Iterator.next() returned a null value");
}
@Override
public final boolean isEmpty() {
return it == null || !it.hasNext();
}
@Override
public final void clear() {
it = null;
}
@Override
public final void request(long n) {
if (SubscriptionHelper.validate(n)) {
if (BackpressureHelper.add(this, n) == 0L) {
if (n == Long.MAX_VALUE) {
fastPath();
} else {
slowPath(n);
}
}
}
}
@Override
public final void cancel() {
cancelled = true;
}
abstract void fastPath();
abstract void slowPath(long r);
}
static final class IteratorSubscription<T> extends BaseRangeSubscription<T> {
private static final long serialVersionUID = -6022804456014692607L;
final Subscriber<? super T> downstream;
IteratorSubscription(Subscriber<? super T> actual, Iterator<? extends T> it) {
super(it);
this.downstream = actual;
}
@Override
void fastPath() {
Iterator<? extends T> it = this.it;
Subscriber<? super T> a = downstream;
for (;;) {
if (cancelled) {
return;
}
T t;
try {
t = it.next();
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
a.onError(ex);
return;
}
if (cancelled) {
return;
}
if (t == null) {
a.onError(new NullPointerException("Iterator.next() returned a null value"));
return;
} else {
a.onNext(t);
}
if (cancelled) {
return;
}
boolean b;
try {
b = it.hasNext();
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
a.onError(ex);
return;
}
if (!b) {
if (!cancelled) {
a.onComplete();
}
return;
}
}
}
@Override
void slowPath(long r) {
long e = 0L;
Iterator<? extends T> it = this.it;
Subscriber<? super T> a = downstream;
for (;;) {
while (e != r) {
if (cancelled) {
return;
}
T t;
try {
t = it.next();
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
a.onError(ex);
return;
}
if (cancelled) {
return;
}
if (t == null) {
a.onError(new NullPointerException("Iterator.next() returned a null value"));
return;
} else {
a.onNext(t);
}
if (cancelled) {
return;
}
boolean b;
try {
b = it.hasNext();
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
a.onError(ex);
return;
}
if (!b) {
if (!cancelled) {
a.onComplete();
}
return;
}
e++;
}
r = get();
if (e == r) {
r = addAndGet(-e);
if (r == 0L) {
return;
}
e = 0L;
}
}
}
}
static final class IteratorConditionalSubscription<T> extends BaseRangeSubscription<T> {
private static final long serialVersionUID = -6022804456014692607L;
final ConditionalSubscriber<? super T> downstream;
IteratorConditionalSubscription(ConditionalSubscriber<? super T> actual, Iterator<? extends T> it) {
super(it);
this.downstream = actual;
}
@Override
void fastPath() {
Iterator<? extends T> it = this.it;
ConditionalSubscriber<? super T> a = downstream;
for (;;) {
if (cancelled) {
return;
}
T t;
try {
t = it.next();
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
a.onError(ex);
return;
}
if (cancelled) {
return;
}
if (t == null) {
a.onError(new NullPointerException("Iterator.next() returned a null value"));
return;
} else {
a.tryOnNext(t);
}
if (cancelled) {
return;
}
boolean b;
try {
b = it.hasNext();
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
a.onError(ex);
return;
}
if (!b) {
if (!cancelled) {
a.onComplete();
}
return;
}
}
}
@Override
void slowPath(long r) {
long e = 0L;
Iterator<? extends T> it = this.it;
ConditionalSubscriber<? super T> a = downstream;
for (;;) {
while (e != r) {
if (cancelled) {
return;
}
T t;
try {
t = it.next();
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
a.onError(ex);
return;
}
if (cancelled) {
return;
}
boolean b;
if (t == null) {
a.onError(new NullPointerException("Iterator.next() returned a null value"));
return;
} else {
b = a.tryOnNext(t);
}
if (cancelled) {
return;
}
boolean hasNext;
try {
hasNext = it.hasNext();
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
a.onError(ex);
return;
}
if (!hasNext) {
if (!cancelled) {
a.onComplete();
}
return;
}
if (b) {
e++;
}
}
r = get();
if (e == r) {
r = addAndGet(-e);
if (r == 0L) {
return;
}
e = 0L;
}
}
}
}
}