src/main/java/io/reactivex/parallel/ParallelFlowable.java
@CheckReturnValue
    @NonNull
    public final ParallelFlowable<T> doOnError(@NonNull Consumer<Throwable> onError) {
        ObjectHelper.requireNonNull(onError, "onError is null");
        return RxJavaPlugins.onAssembly(new ParallelPeek<T>(this,
                Functions.emptyConsumer(),
                Functions.emptyConsumer(),
                onError,
                Functions.EMPTY_ACTION,
                Functions.EMPTY_ACTION,
                Functions.emptyConsumer(),
                Functions.EMPTY_LONG_CONSUMER,
                Functions.EMPTY_ACTION
                ));
    }
@CheckReturnValue
    @NonNull
    public final ParallelFlowable<T> doOnError(@NonNull Consumer<Throwable> onError) {
        ObjectHelper.requireNonNull(onError, "onError is null");
        return RxJavaPlugins.onAssembly(new ParallelPeek<T>(this,
                Functions.emptyConsumer(),
                Functions.emptyConsumer(),
                onError,
                Functions.EMPTY_ACTION,
                Functions.EMPTY_ACTION,
                Functions.emptyConsumer(),
                Functions.EMPTY_LONG_CONSUMER,
                Functions.EMPTY_ACTION
                ));
    }
@ CheckReturnValue @ NonNull public final ParallelFlowable < T > doOnError ( @ NonNull Consumer < Throwable > onError ) { ObjectHelper . requireNonNull ( onError , "onError is null" ) ; return RxJavaPlugins . onAssembly ( new ParallelPeek < T > ( this , Functions . emptyConsumer ( ) , Functions . emptyConsumer ( ) , onError , Functions . EMPTY_ACTION , Functions . EMPTY_ACTION , Functions . emptyConsumer ( ) , Functions . EMPTY_LONG_CONSUMER , Functions . EMPTY_ACTION ) ) ; }
Call the specified consumer with the exception passing through any 'rail'.

@param onError the callback
@return the new ParallelFlowable instance
Call the specified consumer with the exception passing through any rail .