package com.ruoyi.common.utils; import java.text.SimpleDateFormat; import java.util.Date; import java.util.Random; import java.util.concurrent.atomic.AtomicInteger; public class RandomUtil { /** * 字符串池 */ private static String[] STR_ARR = new String[]{"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "1", "2", "3", "4", "5", "6", "7", "8", "9", "0"}; /** * 根据指定的长度生成的含有大小写字母及数字的字符串 * * @param length 指定的长度 * @return 按照指定的长度生成的含有大小写字母及数字的字符串 */ public static String generateRandomString(int length) { StringBuilder sb = new StringBuilder(); Random rand = new Random(); for (int i = 0; i < length; i++) { sb.append(STR_ARR[rand.nextInt(STR_ARR.length)]); } return sb.toString(); } public static void main(String[] args) { String s = generateRandomString(26); System.out.println(s); System.out.println(generateOrderNumber(10L, "NC")); } private static final Random RANDOM = new Random(); private static final AtomicInteger SEQUENCE = new AtomicInteger(0); private static final int MAX_SEQUENCE = 99999;// 5位数的序列号 private static final String ORDER_PER = "SN"; public static String generateOrderNumber(Long dataId, String orderType) { String datePart = new SimpleDateFormat("yyyyMMddhhmm").format(new Date()); int randomPart = RANDOM.nextInt(90000) + 10000; // 生成5位随机数 return orderType + datePart + String.format("%05d", randomPart) + dataId; } }