java取某小数后N位，经典小例子

import java.util.*;class  MathDemo{public static void main(String[] args) {saveTwo(12.3456,2,true);//12.34}public static void saveTwo(double d,int scale,boolean isRound){//需要注意base的取值类型为doubledouble base = Math.pow(10,scale);double num = isRound?Math.round(d*base)/base:((int)(d*base))/base;sop("num="+num);}public static void sop(Object obj){System.out.println(obj);}}