Base58簡(jiǎn)介

Base58采用的字符集合為“123456789abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ”，從這不難看出，Base58是純數(shù)字與字母組成而且去掉了容易引起視覺(jué)混淆的字符（0：數(shù)字零，O：大寫(xiě)O，I：大寫(xiě)i，l:小寫(xiě)L）。9個(gè)數(shù)字+49個(gè)字母=58個(gè)。由于沒(méi)有特殊字符所以在采用鼠標(biāo)雙擊或移動(dòng)設(shè)備選擇時(shí)可以自動(dòng)識(shí)別全選。

Base58本身就是URLSafe。Base64的URFSafe模式雖然已經(jīng)對(duì)URL支持的比較好，但UUID中還是包含“-或_”。

目前流行的比特幣，采用的就是Base58Check編碼，是在Base58基礎(chǔ)上又增加了安全效驗(yàn)機(jī)制。

三、Base58編碼器程序

由于Base58最近才興起，Java與Apache Commons中并不包含編碼器。

package org.noahx.uuid.utils;import java.io.UnsupportedEncodingException; import java.math.BigInteger;/*** Created with IntelliJ IDEA.* User: noah* Date: 8/2/13* Time: 10:36 AM* To change this template use File | Settings | File Templates.*/ public class Base58 {public static final char[] ALPHABET = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz".toCharArray();private static final int[] INDEXES = new int[128];static {for (int i = 0; i < INDEXES.length; i++) {INDEXES[i] = -1;}for (int i = 0; i < ALPHABET.length; i++) {INDEXES[ALPHABET[i]] = i;}}/*** Encodes the given bytes in base58. No checksum is appended.*/public static String encode(byte[] input) {if (input.length == 0) {return "";}input = copyOfRange(input, 0, input.length);// Count leading zeroes.int zeroCount = 0;while (zeroCount < input.length && input[zeroCount] == 0) {++zeroCount;}// The actual encoding.byte[] temp = new byte[input.length * 2];int j = temp.length;int startAt = zeroCount;while (startAt < input.length) {byte mod = divmod58(input, startAt);if (input[startAt] == 0) {++startAt;}temp[--j] = (byte) ALPHABET[mod];}// Strip extra '1' if there are some after decoding.while (j < temp.length && temp[j] == ALPHABET[0]) {++j;}// Add as many leading '1' as there were leading zeros.while (--zeroCount >= 0) {temp[--j] = (byte) ALPHABET[0];}byte[] output = copyOfRange(temp, j, temp.length);try {return new String(output, "US-ASCII");} catch (UnsupportedEncodingException e) {throw new RuntimeException(e); // Cannot happen. }}public static byte[] decode(String input) throws IllegalArgumentException {if (input.length() == 0) {return new byte[0];}byte[] input58 = new byte[input.length()];// Transform the String to a base58 byte sequencefor (int i = 0; i < input.length(); ++i) {char c = input.charAt(i);int digit58 = -1;if (c >= 0 && c < 128) {digit58 = INDEXES[c];}if (digit58 < 0) {throw new IllegalArgumentException("Illegal character " + c + " at " + i);}input58[i] = (byte) digit58;}// Count leading zeroesint zeroCount = 0;while (zeroCount < input58.length && input58[zeroCount] == 0) {++zeroCount;}// The encodingbyte[] temp = new byte[input.length()];int j = temp.length;int startAt = zeroCount;while (startAt < input58.length) {byte mod = divmod256(input58, startAt);if (input58[startAt] == 0) {++startAt;}temp[--j] = mod;}// Do no add extra leading zeroes, move j to first non null byte.while (j < temp.length && temp[j] == 0) {++j;}return copyOfRange(temp, j - zeroCount, temp.length);}public static BigInteger decodeToBigInteger(String input) throws IllegalArgumentException {return new BigInteger(1, decode(input));}//// number -> number / 58, returns number % 58// private static byte divmod58(byte[] number, int startAt) {int remainder = 0;for (int i = startAt; i < number.length; i++) {int digit256 = (int) number[i] & 0xFF;int temp = remainder * 256 + digit256;number[i] = (byte) (temp / 58);remainder = temp % 58;}return (byte) remainder;}//// number -> number / 256, returns number % 256// private static byte divmod256(byte[] number58, int startAt) {int remainder = 0;for (int i = startAt; i < number58.length; i++) {int digit58 = (int) number58[i] & 0xFF;int temp = remainder * 58 + digit58;number58[i] = (byte) (temp / 256);remainder = temp % 256;}return (byte) remainder;}private static byte[] copyOfRange(byte[] source, int from, int to) {byte[] range = new byte[to - from];System.arraycopy(source, from, range, 0, range.length);return range;}}

UUID生成程序

這個(gè)生成UUID程序包含了Base64(URLSafe)與Base58兩種編碼。

package org.noahx.uuid.util;import org.apache.commons.codec.binary.Base64;import java.nio.ByteBuffer; import java.util.UUID;public abstract class UuidUtils {public static String uuid() {UUID uuid = UUID.randomUUID();return uuid.toString();}public static String base64Uuid() {UUID uuid = UUID.randomUUID();return base64Uuid(uuid);}protected static String base64Uuid(UUID uuid) {ByteBuffer bb = ByteBuffer.wrap(new byte[16]);bb.putLong(uuid.getMostSignificantBits());bb.putLong(uuid.getLeastSignificantBits());return Base64.encodeBase64URLSafeString(bb.array());}public static String encodeBase64Uuid(String uuidString) {UUID uuid = UUID.fromString(uuidString);return base64Uuid(uuid);}public static String decodeBase64Uuid(String compressedUuid) {byte[] byUuid = Base64.decodeBase64(compressedUuid);ByteBuffer bb = ByteBuffer.wrap(byUuid);UUID uuid = new UUID(bb.getLong(), bb.getLong());return uuid.toString();}public static String base58Uuid() {UUID uuid = UUID.randomUUID();return base58Uuid(uuid);}protected static String base58Uuid(UUID uuid) {ByteBuffer bb = ByteBuffer.wrap(new byte[16]);bb.putLong(uuid.getMostSignificantBits());bb.putLong(uuid.getLeastSignificantBits());return Base58.encode(bb.array());}public static String encodeBase58Uuid(String uuidString) {UUID uuid = UUID.fromString(uuidString);return base58Uuid(uuid);}public static String decodeBase58Uuid(String base58uuid) {byte[] byUuid = Base58.decode(base58uuid);ByteBuffer bb = ByteBuffer.wrap(byUuid);UUID uuid = new UUID(bb.getLong(), bb.getLong());return uuid.toString();} }

生成UUID的效果

1、Base64的效果

M0ISICCxQi6sP-KIq3kFOw 11YozyYYTvKmuUXpRDvoJA KlZnS-MuT2m3d-the2chxg 8J3SC10AQzqZr6Im8V2xYA ES1UiFTGTHqn6ADU5YW0aw 1usa208oT1q7FitKbQHH5Q 53aDQZxKTGyqmKCzDnBwYQ SVVjViEoQXayWB9_JknKqQ fP6znJIAT1uGMN9HW5o8cw YR-2-kKmSOubhGr2LpFCgQ

可以看到有-與_字符。大家可以雙擊上面包含-的UUID，得到只選中部分的效果。

2、Base58的效果

MqJqC2rtZLkuHys6ed2Eai QrS5w2t5etpRY3zTR1BAEJ Qd6wcFFVz2ZSQb3voGGj8P 75bJdWMcEh6NhT51D5Uyju 2L7kTgsktxMBKLkfAo2iWC UX2Twhbt1kstRziqc7iwCR 9tZNKCeR93taLHU6PVy8hN HSn6JMibca4nG9URWokpwg 8eL4SNz2a4puEW8fD4njsG GThFxPsdVUoZMfmKoEHwQX

Base58與Base64(URLSafe)一樣也只需21或22個(gè)字符就可以標(biāo)示128位的UUID數(shù)據(jù)。基本一樣的長(zhǎng)度，看上去更舒服，當(dāng)然以后就采用Base58來(lái)生成UUID。配合Hibernate的UUID生成器

轉(zhuǎn)載于:https://www.cnblogs.com/suncj/p/4230459.html

總結(jié)

以上是生活随笔為你收集整理的生成Base58格式的UUID（Hibernate Base64格式的UUID续）的全部?jī)?nèi)容，希望文章能夠幫你解決所遇到的問(wèn)題。

如果覺(jué)得生活随笔網(wǎng)站內(nèi)容還不錯(cuò)，歡迎將生活随笔推薦給好友。