/**
* 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.maybe;
import io.reactivex.*;
import io.reactivex.disposables.
Disposable;
import io.reactivex.exceptions.*;
import io.reactivex.functions.
Function;
import io.reactivex.internal.disposables.
DisposableHelper;
import io.reactivex.internal.functions.
ObjectHelper;
/**
* Returns a value generated via a function if the main source signals an onError.
* @param <T> the value type
*/
public final class
MaybeOnErrorReturn<T> extends
AbstractMaybeWithUpstream<T, T> {
final
Function<? super
Throwable, ? extends T>
valueSupplier;
public
MaybeOnErrorReturn(
MaybeSource<T>
source,
Function<? super
Throwable, ? extends T>
valueSupplier) {
super(
source);
this.
valueSupplier =
valueSupplier;
}
@
Override
protected void
subscribeActual(
MaybeObserver<? super T>
observer) {
source.
subscribe(new
OnErrorReturnMaybeObserver<T>(
observer,
valueSupplier));
}
static final class
OnErrorReturnMaybeObserver<T> implements
MaybeObserver<T>,
Disposable {
final
MaybeObserver<? super T>
downstream;
final
Function<? super
Throwable, ? extends T>
valueSupplier;
Disposable upstream;
OnErrorReturnMaybeObserver(
MaybeObserver<? super T>
actual,
Function<? super
Throwable, ? extends T>
valueSupplier) {
this.
downstream =
actual;
this.
valueSupplier =
valueSupplier;
}
@
Override
public void
dispose() {
upstream.
dispose();
}
@
Override
public boolean
isDisposed() {
return
upstream.
isDisposed();
}
@
Override
public void
onSubscribe(
Disposable d) {
if (
DisposableHelper.
validate(this.
upstream,
d)) {
this.
upstream =
d;
downstream.
onSubscribe(this);
}
}
@
Override
public void
onSuccess(T
value) {
downstream.
onSuccess(
value);
}
@
Override
public void
onError(
Throwable e) {
T
v;
try {
v =
ObjectHelper.
requireNonNull(
valueSupplier.
apply(
e), "The valueSupplier returned a null value");
} catch (
Throwable ex) {
Exceptions.
throwIfFatal(
ex);
downstream.
onError(new
CompositeException(
e,
ex));
return;
}
downstream.
onSuccess(
v);
}
@
Override
public void
onComplete() {
downstream.
onComplete();
}
}
}