export declare class PortManager {
    private readonly start;
    private readonly end;
    private readonly reservedPorts;
    private static readonly MAX_RETRIES;
    constructor(start: number, end: number, reservedPorts?: number[]);
    /**
     * Returns an unused port within the given range and reserve it on the PortManager instance.
     */
    reserveUnusedPort(): Promise<number>;
    /**
     * Returns an unused port within the given range.
     */
    getUnusedPort(): Promise<number>;
    /**
     * This function is designated to get reserved ports for EPS main services, so that
     * extractors may skip these ports during start.
     *
     * It must be called after all EPS main services have started, e.g. static server,
     * eps api, grpc server, etc. Otherwise, it could potentially cause race condition,
     * since the port detection is async.
     */
    getReservedPorts(): number[];
    getPortRange(): [number, number];
    /**
     * Get a random port number within [min, max] (both inclusively) without checking
     * port availability.
     */
    private getRandomPortNumber;
}