/*
* 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.
Iterator;
import java.util.
Objects;
import java.util.
Queue;
import java.util.concurrent.
Callable;
import java.util.function.
Function;
import java.util.function.
Supplier;
import reactor.core.
CoreSubscriber;
import reactor.core.
Fuseable;
/**
* Concatenates values from Iterable sequences generated via a mapper function.
*
* @param <T> the input value type
* @param <R> the value type of the iterables and the result type
*
* @see <a href="https://github.com/reactor/reactive-streams-commons">Reactive-Streams-Commons</a>
*/
final class
MonoFlattenIterable<T, R> extends
FluxFromMonoOperator<T, R>
implements
Fuseable {
final
Function<? super T, ? extends
Iterable<? extends R>>
mapper;
final int
prefetch;
final
Supplier<
Queue<T>>
queueSupplier;
MonoFlattenIterable(
Mono<? extends T>
source,
Function<? super T, ? extends
Iterable<? extends R>>
mapper,
int
prefetch,
Supplier<
Queue<T>>
queueSupplier) {
super(
source);
if (
prefetch <= 0) {
throw new
IllegalArgumentException("prefetch > 0 required but it was " +
prefetch);
}
this.
mapper =
Objects.
requireNonNull(
mapper, "mapper");
this.
prefetch =
prefetch;
this.
queueSupplier =
Objects.
requireNonNull(
queueSupplier, "queueSupplier");
}
@
Override
public int
getPrefetch() {
return
prefetch;
}
@
SuppressWarnings("unchecked")
@
Override
public void
subscribe(
CoreSubscriber<? super R>
actual) {
if (
source instanceof
Callable) {
T
v;
try {
v = ((
Callable<T>)
source).
call();
}
catch (
Throwable ex) {
Operators.
error(
actual,
Operators.
onOperatorError(
ex,
actual.
currentContext()));
return;
}
if (
v == null) {
Operators.
complete(
actual);
return;
}
Iterator<? extends R>
it;
try {
Iterable<? extends R>
iter =
mapper.
apply(
v);
it =
iter.
iterator();
}
catch (
Throwable ex) {
Operators.
error(
actual,
Operators.
onOperatorError(
ex,
actual.
currentContext()));
return;
}
FluxIterable.
subscribe(
actual,
it);
return;
}
source.
subscribe(new
FluxFlattenIterable.
FlattenIterableSubscriber<>(
actual,
mapper,
prefetch,
queueSupplier));
}
}