io.reactivex.internal.operators.observable.ObservableLift Maven / Gradle / Ivy
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/**
* 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.observable;
import io.reactivex.*;
import io.reactivex.exceptions.Exceptions;
import io.reactivex.internal.functions.ObjectHelper;
import io.reactivex.plugins.RxJavaPlugins;
/**
* Allows lifting operators into a chain of Observables.
*
* By having a concrete ObservableSource as lift, operator fusing can now identify
* both the source and the operation inside it via casting, unlike the lambda version of this.
*
* @param the upstream value type
* @param the downstream parameter type
*/
public final class ObservableLift extends AbstractObservableWithUpstream {
/** The actual operator. */
final ObservableOperator operator;
public ObservableLift(ObservableSource source, ObservableOperator operator) {
super(source);
this.operator = operator;
}
@Override
public void subscribeActual(Observer observer) {
Observer liftedObserver;
try {
liftedObserver = ObjectHelper.requireNonNull(operator.apply(observer), "Operator " + operator + " returned a null Observer");
} catch (NullPointerException e) { // NOPMD
throw e;
} catch (Throwable e) {
Exceptions.throwIfFatal(e);
// can't call onError because no way to know if a Disposable has been set or not
// can't call onSubscribe because the call might have set a Disposable already
RxJavaPlugins.onError(e);
NullPointerException npe = new NullPointerException("Actually not, but can't throw other exceptions due to RS");
npe.initCause(e);
throw npe;
}
source.subscribe(liftedObserver);
}
}