rx.internal.operators.OnSubscribeFromCallable Maven / Gradle / Ivy
package rx.internal.operators;
import rx.Observable;
import rx.Subscriber;
import rx.exceptions.Exceptions;
import rx.internal.producers.SingleDelayedProducer;
import java.util.concurrent.Callable;
/**
* Do not invoke the function until an Observer subscribes; Invokes function on each
* subscription.
*
* Pass {@code fromCallable} a function, and {@code fromCallable} will call this function to emit result of invocation
* afresh each time a new Observer subscribes.
*/
public final class OnSubscribeFromCallable implements Observable.OnSubscribe {
private final Callable resultFactory;
public OnSubscribeFromCallable(Callable resultFactory) {
this.resultFactory = resultFactory;
}
@Override
public void call(Subscriber subscriber) {
final SingleDelayedProducer singleDelayedProducer = new SingleDelayedProducer(subscriber);
subscriber.setProducer(singleDelayedProducer);
try {
singleDelayedProducer.setValue(resultFactory.call());
} catch (Throwable t) {
Exceptions.throwIfFatal(t);
subscriber.onError(t);
}
}
}