import { KeyValue } from '../key-value';
import * as i0 from "@angular/core";
export declare class PersistentStorageService {
    getJson<T = KeyValue>(key: string): T | null;
    setJson(key: string, value: object): void;
    getItem(key: string): string | null;
    setItem(key: string, value: string): void;
    clear(): void;
    removeItem(key: string): void;
    static ɵfac: i0.ɵɵFactoryDeclaration<PersistentStorageService, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<PersistentStorageService>;
}