function DBWrite(){
var address ='202.47.118.131:3306';
var user = "root";
var pwd="";
var db= "smsbrn";
var cform=FormApp.getActiveForm();
var formId=cform.getId();
var dbUrl='jdbc:mysql://' + address + '/' + db;

***var conn=Jdbc.getConnection(dbUrl, user, pwd);** //connection fails here.*

 }