import InMemoryStorage from '../InMemoryStorage';
/**
 * Reads key-value pairs from a JSON file and writes them back.
 * It is recommended to create it with the static create(...) factory instead of the sync constructor.
 */
export default class JsonStorage extends InMemoryStorage {
    /**
     * Initializes the JsonStorage. It's advised to use the async static factory method create(...) instead.
     * @param file Path to the JSON file (must be read- and writable)
     */
    constructor(file?: string);
    private file;
    /**
     * Factory for a JsonStorage object that initializes the object.
     * Throws errors is something is wrong with the file (not accessible / can't be parsed).
     * @param file Path to the JSON file (must be read- and writeable)
     */
    static create(file: string): Promise<JsonStorage>;
    /**
     * Saves a key in the JSON file (supports nested values).
     * @param key
     * @param value
     */
    save(key: string, value: any): Promise<any>;
    /**
     * Initializes the storage by loading the JSON file.
     * @param file Path to the JSON file (must be read- and writeable)
     */
    private initialize;
}