数学计算工具类,以后备用
import java.text.DecimalFormat;import java.text.NumberFormat;import java.util.Random;/** * 数学计算工具类 * @author <a href="mailto:zhsj0110@163.com">zhoushijun</a> * */public class MathUtil {/** * a除以b的整数,向上取整. * * @param divHeader * int * @param divUnder * int * @return int */public static int ceildiv(int divHeader, int divUnder) {return (int) Math.ceil((double) divHeader / (double) divUnder);}/** * 返回两个数相除的结果,按照nSyo的格式输出. 格式说明参考NumberFormat的帮助. * * @param divHeader * 被除数 * @param divUnder * 除数 * @param nSyo * 格式 * @return String */public static String mydiv(int divHeader, int divUnder, String nSyo) {if (divHeader == 0 || divUnder == 0) {return "0.0";}NumberFormat astr = NumberFormat.getInstance();((DecimalFormat) astr).applyPattern(nSyo);return astr.format((double) divHeader / (double) divUnder);}/** * 得到一个随机整数,最大是n. * * @param nMax * 最大值 * @return 输出:随机整数 */public static int getRandom(int nMax) {Random hello;hello = new Random();return hello.nextInt(nMax);}/** * 得到随机数,加上字符串前缀. * * @param nMax * 随机数的最大值 * @param strPre * 字符串前缀 * @return 字符串前缀加上随机数 */public static String getRandom(int nMax, String strPre) {Random hello = new Random();String result = strPre + hello.nextInt(nMax);return result;}}?