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.single; import io.reactivex.Maybe; import io.reactivex.MaybeObserver; import io.reactivex.MaybeSource; import io.reactivex.SingleObserver; import io.reactivex.SingleSource; import io.reactivex.disposables.Disposable; import io.reactivex.exceptions.Exceptions; import io.reactivex.functions.Function; import io.reactivex.internal.disposables.DisposableHelper; import io.reactivex.internal.functions.ObjectHelper; import java.util.concurrent.atomic.AtomicReference; public final class SingleFlatMapMaybe<T, R> extends Maybe<R> { final SingleSource<? extends T> source; final Function<? super T, ? extends MaybeSource<? extends R>> mapper; public SingleFlatMapMaybe(SingleSource<? extends T> source, Function<? super T, ? extends MaybeSource<? extends R>> mapper) { this.mapper = mapper; this.source = source; } @Override protected void subscribeActual(MaybeObserver<? super R> downstream) { source.subscribe(new FlatMapSingleObserver<T, R>(downstream, mapper)); } static final class FlatMapSingleObserver<T, R> extends AtomicReference<Disposable> implements SingleObserver<T>, Disposable { private static final long serialVersionUID = -5843758257109742742L; final MaybeObserver<? super R> downstream; final Function<? super T, ? extends MaybeSource<? extends R>> mapper; FlatMapSingleObserver(MaybeObserver<? super R> actual, Function<? super T, ? extends MaybeSource<? extends R>> mapper) { this.downstream = actual; this.mapper = mapper; } @Override public void dispose() { DisposableHelper.dispose(this); } @Override public boolean isDisposed() { return DisposableHelper.isDisposed(get()); } @Override public void onSubscribe(Disposable d) { if (DisposableHelper.setOnce(this, d)) { downstream.onSubscribe(this); } } @Override public void onSuccess(T value) { MaybeSource<? extends R> ms; try { ms = ObjectHelper.requireNonNull(mapper.apply(value), "The mapper returned a null MaybeSource"); } catch (Throwable ex) { Exceptions.throwIfFatal(ex); onError(ex); return; } if (!isDisposed()) { ms.subscribe(new FlatMapMaybeObserver<R>(this, downstream)); } } @Override public void onError(Throwable e) { downstream.onError(e); } } static final class FlatMapMaybeObserver<R> implements MaybeObserver<R> { final AtomicReference<Disposable> parent; final MaybeObserver<? super R> downstream; FlatMapMaybeObserver(AtomicReference<Disposable> parent, MaybeObserver<? super R> downstream) { this.parent = parent; this.downstream = downstream; } @Override public void onSubscribe(final Disposable d) { DisposableHelper.replace(parent, d); } @Override public void onSuccess(final R value) { downstream.onSuccess(value); } @Override public void onError(final Throwable e) { downstream.onError(e); } @Override public void onComplete() { downstream.onComplete(); } } }