Java 58进制与十进制互转

1、原理

0-10、a-z、A-Z，去除不好辨识的字符，例如大写O、小写l等，共凑成58个字符数组。传入long型数据，递归对58进行取模取余，进行进制转换。

2、代码

package com.lyn.v5.polish.infrastructure.utils;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.HashMap;

public class InvitationCodeUtils {
    private static final Logger logger = LoggerFactory.getLogger(InvitationCodeUtils.class);
    private static final char[] charArray = "0123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnpqrstuvwxyz".toCharArray();
    private static final int scale = 58;
    private static final HashMap<String, Integer> map = new HashMap<String, Integer>() {
        {
            put("0", 0);
            put("1", 1);
            put("2", 2);
            put("3", 3);
            put("4", 4);
            put("5", 5);
            put("6", 6);
            put("7", 7);
            put("8", 8);
            put("9", 9);
            put("A", 10);
            put("B", 11);
            put("C", 12);
            put("D", 13);
            put("E", 14);
            put("F", 15);
            put("G", 16);
            put("H", 17);
            put("J", 18);
            put("K", 19);
            put("L", 20);
            put("M", 21);
            put("N", 22);
            put("P", 23);
            put("Q", 24);
            put("R", 25);
            put("S", 26);
            put("T", 27);
            put("U", 28);
            put("V", 29);
            put("W", 30);
            put("X", 31);
            put("Y", 32);
            put("Z", 33);
            put("a", 34);
            put("b", 35);
            put("c", 36);
            put("d", 37);
            put("e", 38);
            put("f", 39);
            put("g", 40);
            put("h", 41);
            put("i", 42);
            put("j", 43);
            put("k", 44);
            put("m", 45);
            put("n", 46);
            put("p", 47);
            put("q", 48);
            put("r", 49);
            put("s", 50);
            put("t", 51);
            put("u", 52);
            put("v", 53);
            put("w", 54);
            put("x", 55);
            put("y", 56);
            put("z", 57);
        }
    };

    public static String encodeStr(Long num) {
        StringBuilder sb = new StringBuilder();
        try {
            while (num != 0) {
                sb.append(charArray[(int) (num % scale)]);
                num = num / scale;
            }
            return sb.toString();
        } catch (Exception ex) {
            logger.error("InvitationCodeUtils encodeStr 编码出错", ex);
        }
        return "";
    }

    public static String decodeStr(String str) {
        long sum = 0;
        try {
            for (int i = str.length() - 1; i >= 0; i--) {
                sum += Math.pow(scale, i) * map.get(str.charAt(i) + "");
            }
            return String.valueOf(sum);
        } catch (Exception ex) {
            logger.error("InvitationCodeUtils decodeStr 输入不符合规范");
        }
        return "";
    }

    public static void main(String[] args) {
        String mobile = "13100012345";
        String mobileEn = encodeStr(Long.parseLong(mobile));
        logger.info("手机号={} 编码后={}", mobile, mobileEn);
        String mobileDe = decodeStr(mobileEn);
        logger.info("编码后={} 解码后={}", mobileEn, mobileDe);
    }

}

3、执行结果