In order to determine the stress associated with each line, it is necessary to calibrate the coating. 为了决定每条线所对应的应力，需对涂层进行标定。
That means that if you want to make a nonprimitive object on the heap to represent that primitive type, you use the associated wrapper. 这意味着假如想让堆内一个非主要对象表示那个主类型，就要使用对应的封装器。
