import { ExtraParameters, Filter } from "../models/index";
import { FilterService } from "./filterService";
export declare class HttpParamService extends FilterService<string> {
    constructor();
    /**
     * Returns all values as field=value
     *
     * @param filter
     */
    getFilterValue(filter: Filter, extraParameters?: ExtraParameters): string;
    /** @inheritdoc */
    getFilter(url: string): Filter;
    /**
     * Pass all sortitems as SortField=SortDirection
     * direction will be passed as + or -
     *
     * @param sortItems
     */
    private addSorts;
    /**
     * Add all filterItems as filterField=Value.
     * Add duplicate field/value declaration if multiple values exist.
     *
     * @param filterItems
     */
    private addFilters;
}