logging - How to check if an specific logger exists in Logback -

basically need check if specific logger exists can change level. following pseudo-code:

logger mylogger =  (logger) loggerfactory.getlogger( "com.logger.to.change");  if ( validatethatloggerexist (mylogger))  // check logger exist    mylogger.setleve(level.new_level)     // change logger log level else    throw new loggernotfoundexeption()   // somethig 

    string loggername = "com.logger.to.change";     loggercontext loggercontext = (loggercontext) loggerfactory                     .getiloggerfactory();     logger logger = loggercontext.exists(loggername); //returns logger if exists else returns null      if(logger != null){         logger.setlevel(level.new_level)     }else{         throw new loggernotfoundexeption()   //     }