import { AnyFn } from '../../../shared/types';
import { AsyncQueueDefine } from './types';
export * from './types';
export declare enum ENTRY_STATE {
    PENDING = 0,
    DONE = 1
}
/**
 * @constructor 并发控制器
 */
export declare class AsyncQueue<T = any, K = any, R = any> {
    readonly name: string;
    private readonly processor;
    private readonly getKey;
    parallelism: number;
    private readonly _queued;
    private readonly _entries;
    private _activeTasks;
    private _processingLock;
    private _stopped;
    uniqueData: boolean;
    constructor({ name, processor, getKey, parallelism, uniqueData }: AsyncQueueDefine.CreatorOptions<T>);
    add(item: T, callback: AsyncQueueDefine.EntryCallback): void;
    addAsync(item: T): Promise<R>;
    private _ensureProcessing;
    private _startProcess;
    private _handlerResult;
    get activeTasks(): number;
    onActiveTaskChange: null | AnyFn;
}