/**
 * Message Dispatcher implementation.
 */
export declare class MessageDispatcher {
    private _handlers;
    /**
     * Registers a message handler with a MessageDispatcher.
     *
     * @param message The interesting message
     * @param handler The handler function
     */
    addMessageHandler(message: string, handler: Function): void;
    /**
     * Checks whether the MessageDispatcher has any handlers registered for a specific message.
     *
     * @param message The interesting message
     * @return A value of true if a handler of the specified message is registered; false otherwise.
     */
    hasMessageHandler(message: string): boolean;
    /**
     * Removes a message handler from a MessageDispatcher
     *
     * @param message The interesting message
     * @param handler The handler function
     */
    removeMessageHandler(message: string, handler: Function): void;
    /**
     * Dispatches a message into the message flow.
     *
     * @param message The interesting message
     * @param callback The completion callback function
     * @param reverse Should handlers be called in reverse order
     */
    dispatchMessage(message: string, callback?: Function, reverse?: boolean): void;
}