import { AgoraRtmChannelClientObserver } from './type';
/**
 * Abstract class representing a Agora RTM channel client.
 */
export declare abstract class AgoraRtmChannelClient {
    /**
     * Joins the channel.
     * @returns A promise that resolves when the channel has been joined.
     */
    abstract join(): Promise<number>;
    /**
     * Sends a message to the channel.
     * @param content - The content of the message to send.
     * @returns A promise that resolves when the message has been sent.
     */
    abstract sendMessage(content: string): Promise<number>;
    /**
     * Leaves the channel.
     * @returns A promise that resolves when the channel has been left.
     */
    abstract leave(): Promise<number>;
    /**
     * Adds an observer to the channel.
     * @param observer - The observer to add.
     */
    abstract addObserver(observer: AgoraRtmChannelClientObserver): void;
    /**
     * Removes an observer from the channel.
     * @param observer - The observer to remove.
     */
    abstract removeObserver(observer: AgoraRtmChannelClientObserver): void;
    /**
     * release rtm channel
     */
    abstract release(): void;
}