export declare class CoreUtil {
    private static PLAIN_MAP_OBJECTS;
    private constructor();
    static isRepeatedCharString(str: string): boolean;
    static hasAttributes(param: any): boolean;
    static isDate(param: any): boolean;
    static objectToPlainMap(json: any): Map<string, any>;
    private static doMapAttributes;
    private static objectToPlainMapOld;
    private static doMapAttributesOld;
    static objectToString(object: any): string;
    private static wasProcessed;
    private static markAsProcessed;
}