/**
* 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 java.util.concurrent.
Callable;
import io.reactivex.*;
import io.reactivex.exceptions.
Exceptions;
import io.reactivex.internal.disposables.
EmptyDisposable;
import io.reactivex.internal.functions.
ObjectHelper;
/**
* Defers the creation of the actual Maybe the incoming MaybeObserver is subscribed to.
*
* @param <T> the value type
*/
public final class
MaybeDefer<T> extends
Maybe<T> {
final
Callable<? extends
MaybeSource<? extends T>>
maybeSupplier;
public
MaybeDefer(
Callable<? extends
MaybeSource<? extends T>>
maybeSupplier) {
this.
maybeSupplier =
maybeSupplier;
}
@
Override
protected void
subscribeActual(
MaybeObserver<? super T>
observer) {
MaybeSource<? extends T>
source;
try {
source =
ObjectHelper.
requireNonNull(
maybeSupplier.
call(), "The maybeSupplier returned a null MaybeSource");
} catch (
Throwable ex) {
Exceptions.
throwIfFatal(
ex);
EmptyDisposable.
error(
ex,
observer);
return;
}
source.
subscribe(
observer);
}
}