Jmeter vars取值、转型相关

需求：全局变量、累加计数，非从1开始，String转Int型、Int型转String

samper前置处理level、exp，计算出累加后的值

level=Integer.parseInt(vars.get("level"));
exp=Integer.parseInt(vars.get("exp"));
level=level+1;
exp=exp+50;

vars.put("level",level.toString());
vars.put("exp",exp.toString());