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- package com.ruoyi.common.utils;
- import java.util.Random;
- public class NumberUtils {
- public static String getRandom(int len) {
- int rs = (int) ((Math.random() * 9 + 1) * Math.pow(10, len - 1));
- return String.valueOf(rs);
- }
- public static String getRandom1(int len) {
- Random r = new Random();
- StringBuilder rs = new StringBuilder();
- for (int i = 0; i < len; i++) {
- rs.append(r.nextInt(10));
- }
- return rs.toString();
- }
- public static boolean isNumeric(String str){
- if(StringUtils.isNotEmpty(str)){
- str = str.trim();
- }
- for(int i=str.length();--i>=0;){
- int chr=str.charAt(i);
- if(chr<48 || chr>57){
- return false;
- }
- }
- return true;
- }
- public static void main(String[] args) {
- System.out.println(getRandom1(8));
- System.out.println(getRandom(8));
- }
- }
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