import { IServerListManager, serverListMgrOptions } from './interface';
declare const Base: any;
export declare class ServerListManager extends Base implements IServerListManager {
    private isSync;
    private isClosed;
    private serverListCache;
    private currentUnit;
    /**
     * 服务地址列表管理器
     *
     * @param {Object} options
     *   - {HttpClient} httpclient - http 客户端
     *   - {Snapshot} [snapshot] - 快照对象
     *   - {String} nameServerAddr - 命名服务器地址 `hostname:port`
     * @constructor
     */
    constructor(options: serverListMgrOptions);
    readonly snapshot: any;
    readonly httpclient: any;
    readonly nameServerAddr: any;
    readonly refreshInterval: any;
    /**
     * 关闭地址列表服务
     */
    close(): void;
    private request;
    getCurrentUnit(): Promise<any>;
    /**
     * 获取某个单元的地址
     * @param {String} unit 单元名，默认为当前单元
     * @return {String} address
     */
    getOne(unit?: any): Promise<any>;
    /**
     * 同步服务器列表
     * @return {void}
     */
    syncServers(): void;
    fetchServerList(unit?: any): Promise<{
        hosts: any;
        index: any;
    }>;
    formatKey(unit: any): any;
    private getRequestUrl;
    /**
     * 获取单元列表
     * @return {Array} units
     */
    fetchUnitLists(): Promise<any[]>;
    hasServerInCache(serverName: any): any;
    clearaServerCache(): void;
}
export {};