author Javen
 *  copyright description import { InMsg } from './InMsg' ; export class InTextMsg extends InMsg { private content : string ; private msgId : string ; constructor ( toUserName , fromUserName , createTime , msgType ) { super ( toUserName , fromUserName , createTime , msgType ) ; } public get getContent ( ) : string { return this . content ; } public set setContent ( content ) { this . content = content ; } public get getMsgId ( ) : string { return this . msgId ; } public set setMsgId ( msgId ) { this . msgId = msgId ; } }