reactor-core/src/main/java/reactor/core/publisher/ParallelFlux.java
public final Disposable subscribe(@Nullable Consumer<? super T> onNext, Consumer<? super Throwable>
			onError){
		return subscribe(onNext, onError, null);
	}
public final Disposable subscribe(@Nullable Consumer<? super T> onNext, Consumer<? super Throwable>
			onError){
		return subscribe(onNext, onError, null);
	}
Subscribes to this {@link ParallelFlux} by providing an onNext and onError callback
and triggers the execution chain for all 'rails'.

@param onNext consumer of onNext signals
@param onError consumer of error signal