export declare class NCCache {
    static EXPIRED_A_MINUTE: number;
    static EXPIRED_A_HOUR: number;
    static EXPIRED_A_DAY: number;
    static DEFAULT_EXPIRED_REMAIN: number;
    private storage;
    constructor(isInstant?: boolean);
    private nowInMilli;
    put(key: string, value: string, expiredAfter?: number): void;
    get(key: string): Promise<string | null>;
    putNumber(key: string, value: number, expiredAfter?: number): void;
    putObject<T>(key: string, value: T, expiredAfter?: number): void;
    getNumber(key: string, defaultValue?: number): number;
    getObject<T>(key: string): Promise<T | null>;
}