import { ILoaderReturnValue, Loader } from "./Loader";
export declare class JSONLoader extends Loader<object> {
    private readonly _cache;
    private _queueQueue;
    private _currentQueue;
    add(_key: string, _asset: string): void;
    has(_key: string): boolean;
    cache<T>(_key: string, _asset: T): void;
    get<T>(_key: string): T;
    isAssetLoaded(_key: string): boolean;
    load(_onProgress?: ((progress: number) => void) | undefined): Promise<ILoaderReturnValue>;
    unload(_key: string): void;
}