import type { IAction, IActorArgs, IActorOutput, Mediate } from '@comunica/core';
import { Actor } from '@comunica/core';
import type { IMediatorTypeAccuracy } from '@comunica/mediatortype-accuracy';
import type { IJoinEntry } from '@comunica/types';
/**
 * A comunica actor for rdf-join-selectivity events.
 *
 * Actor types:
 * * Input:  IActionRdfJoinSelectivity:      Join entries.
 * * Test:   IMediatorTypeAccuracy:          The accuracy of the selectivity calculator.
 * * Output: IActorRdfJoinSelectivityOutput: The calculated join selectivity.
 *
 * @see IActionRdfJoinSelectivity
 * @see IActorRdfJoinSelectivityTest
 * @see IActorRdfJoinSelectivityOutput
 */
export declare abstract class ActorRdfJoinSelectivity<TS = undefined> extends Actor<IActionRdfJoinSelectivity, IMediatorTypeAccuracy, IActorRdfJoinSelectivityOutput, TS> {
    /**
     * @param args -
     *   \ @defaultNested {<default_bus> a <cc:components/Bus.jsonld#Bus>} bus
     *   \ @defaultNested {Determining join selectivity failed: none of the configured actors were able to calculate selectivities} busFailMessage
     */
    constructor(args: IActorRdfJoinSelectivityArgs<TS>);
}
export interface IActionRdfJoinSelectivity extends IAction {
    /**
     * The array of streams to join.
     */
    entries: IJoinEntry[];
}
export interface IActorRdfJoinSelectivityOutput extends IActorOutput {
    /**
     * A selectivity factor in the range [0, 1].
     * A value close to 1 indicates a low selectivity,
     * which means that the operations in the join entries are highly unrelated.
     * A value close to 0 indicates a high selectivity,
     * which means that the operations in the join entries are highly related, and have a high chance of reducing .
     */
    selectivity: number;
}
export type IActorRdfJoinSelectivityArgs<TS = undefined> = IActorArgs<IActionRdfJoinSelectivity, IMediatorTypeAccuracy, IActorRdfJoinSelectivityOutput, TS>;
export type MediatorRdfJoinSelectivity = Mediate<IActionRdfJoinSelectivity, IActorRdfJoinSelectivityOutput, IMediatorTypeAccuracy>;