Random code (verification code, SMS code) generation tools

demand

Sometimes it is necessary to use verification codes (random codes) for business processing situations at work, so the tools used in the development have been specially collected, which has been needed from time to time.

The tool code is as follows:

package com.cloud.util;

import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import java.util.logging.Logger;

/**
 * @author raos
 * @emil [email protected]
 * @date 2020/12/25
 * 随机码/预约码/短信码生成工具类
 */
public class MateUtils {
    
    
    private static final Logger log = Logger.getLogger("MateUtils.class");
    /** 预约码码表 */
    private static final char[] CODE_TABLE= {
    
    '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','0','1','2','3','4','5','6','7','8','9'};

    /** 随机码默认位数-- 6位 */
    private static final int DEFAULT_DIGIT = 6;

    /** 默认随机码个数-- 2个 */
    private static final int DEFAULT_NUMBER = 2;

    private MateUtils() {
    
     }

    /**  默认生成单个6位预约码 */
    public static String generateOne() {
    
    
        StringBuilder strBuild = new StringBuilder();
        for (int i = 0; i <= DEFAULT_DIGIT; i++) {
    
    
            strBuild.append(CODE_TABLE[new Random().nextInt(36)]);
        }
        return strBuild.toString();
    }

    /**
     * 指定位数生成随机码，位数需大于0，否则返回默认6位随机码
     * @param digit 随机码的位数
     */
    public static String generateOne(int digit) {
    
    
        if (digit > 0) {
    
    
            StringBuilder strBuild = new StringBuilder();
            for (int i = 0; i <= digit; i++) {
    
    
                strBuild.append(CODE_TABLE[new Random().nextInt(36)]);
            }
            return strBuild.toString();
        }
        return generateOne();
    }

    /**
     * 默认生成 2个 6位随机码
     */
    public static List<String> generateList() {
    
    
        List<String> randomCodes = new ArrayList<>(DEFAULT_NUMBER);
        for (int i = 0; i < DEFAULT_NUMBER; i++) {
    
    
            randomCodes.add(generateOne());
        }
        return randomCodes;
    }

    /**
     * 指定生成随机码个数、位数生成随机码，位数需大于0，否则返回默认6位随机码，个数需大于1，否则默认2个
     * @param number 随机码生成个数
     * @param digit 随机码位数  
     */
    public static List<String> generateList(int number, int digit) {
    
    
        if (number > 1) {
    
    
            List<String> randomCodes = new ArrayList<>(number);
            for (int i = 0; i < number; i++) {
    
    
                randomCodes.add(generateOne(digit));
            }
            return randomCodes;
        }
        return generateList();
    }

    /**
     * 测试入口
     */
    public static void main(String[] args) {
    
    
        log.info("循环开始" + System.currentTimeMillis());
        for (int i = 0; i < 100; i++) {
    
    
            System.out.println(generateOne());
        }
        log.info("循环结束" + System.currentTimeMillis());
    }
}