import LinkedNode from './linked.node';
import { StepIterator } from '../../interface/step';
export default class DoublyLinkedList<T> {
    private readonly queue;
    private firstKey;
    private lastKey;
    constructor();
    isEmpty(): boolean;
    isLast(key: string): boolean;
    getLastKey(): string;
    isFirst(key: string): boolean;
    getFirstKey(): string;
    isExist(key: string): boolean;
    addLastItem(key: string, value: T): boolean;
    addFirstItem(key: string, value: T): boolean;
    addItemAfterKey(key: string, itemKey: string, itemValue: T): boolean;
    addItemBeforeKey(key: string, itemKey: string, itemValue: T): boolean;
    removeItemByKey(key: string): boolean;
    updateItemByKey(key: string, value: T): boolean;
    getValueByKey(key: string): T;
    _getLinkedNodeByKey(key: string): LinkedNode<T>;
    getSize(): number;
    getFisrtItem(): T;
    getLastItem(): T;
    getKeys(): string[];
    createIterator(key?: string): StepIterator<T>;
    addLastItemByList(key: string, queueObject: any): void;
    toJSON(): string;
    clone(): DoublyLinkedList<T>;
    moveupByKey(key: string): void;
    movedownByKey(key: string): void;
    exchangeItemByKey(sourceKey: string, targetKey: string): void;
}