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Java实现BCH与BTC的地址相互转换

news 2025/10/4 6:01:30

文章目录

- 1. 背景
- 2. 踩坑
- 3. 解决思路
- 4. 实现原理
- 5. 实现代码
- 6. 测试代码
- 7.类库依赖
- 8. 小结

1. 背景

接上篇:

Java实现LTC以3和M开头的地址相互转换

BCH和LTC有点类似，用户输入的可能是 BTC 类型的地址, 也可能专有的地址。
上连前，需要统一转换为 BTC 类型的地址。

这样就有一个问题，比对的时候，两者可能需要相互转换，以确定是否等价。

2. 踩坑

这次没有问AI，根据相关的链接，进行转换。

结果死活对应不上。

换言之，也就是网上没有现成的Java版本的地址转换工具类。

3. 解决思路

参考和比对的页面，可以进行转换:

https://cashaddr.bitcoincash.org/

扒开页面一看，里面是使用了 JS 实现，但是却调用了一个后端接口来进行转换。

然后，又找到了一个看着比较靠谱的github仓库:

https://github.com/Electron-Cash/Electron-Cash-Java/blob/master/CashAddr.java

里面有一些基础的Base32的转换逻辑，以及校验和等处理方式。

但是用着还是有点不顺手。

4. 实现原理

BCH和LTC有类似的问题。

实际上各种地址格式之间，不管怎么变，唯一不变的就是 hash 部分。

LTC地址和BCH、BTC地址, 实际上就是一串 21 byte 的数据, 然后序列化为Base58格式的字符串。
第一个 byte 是版本号。

而 bitcoincash 前缀的地址，使用的 Base32 编码，具体的原理则参考上面的部分，因为官方提供了二维码转换，所以这个前缀的地址使用较多。

了解了实现原理，转换步骤很简单:

将Base58格式转换为byte数组
转换为 bitcoincash 前缀格式的地址(Base32)

或者反过来:

解析 bitcoincash 前缀或者该格式的地址(Base32)
再转换为Base58格式的地址

5. 实现代码

实现的逻辑如下:


import lombok.extern.slf4j.Slf4j;
import org.bitcoinj.core.CashAddr;import java.util.HashMap;
import java.util.Map;
import java.util.Objects;import static org.bitcoinj.core.CashAddr.MAIN_NET_PREFIX;
import static org.bitcoinj.core.CashAddr.SEPARATOR;// see: https://github.com/zquestz/cashaddr-converter
// see: https://cashaddr.bitcoincash.org/?utm@Slf4j
public class BCHAddressUtil {public static String toAnoAddr(String bchAddr) {// 判断地址类型boolean isValidCashAddress = CashAddr.isValidCashAddress(bchAddr);try {if (!isValidCashAddress) {// 转换base58, 并提取 hashLTCAddressUtil.BtcAddr btcAddr = LTCAddressUtil.BtcAddr.from(bchAddr);byte[] hash = btcAddr.getHash();// 转换地址CashAddr.BitcoinCashAddressType targetType = CashAddr.BitcoinCashAddressType.P2PKH;String other = CashAddr.toCashAddress(targetType, hash);return trimPrefix(other);} else {// 解析CashAddr.BitcoinCashAddressDecodedParts decoded = CashAddr.decodeCashAddress(bchAddr);byte[] hash = decoded.getHash();byte version = CashAddr.BitcoinCashAddressType.P2PKH.getVersionByte();// 转换地址LTCAddressUtil.BtcAddr btcAddr = new LTCAddressUtil.BtcAddr();btcAddr.setHash(hash);btcAddr.setVersion(version);String other = btcAddr.getAddrStr();return other;}} catch (Exception e) {log.warn("转换BCH地址失败, 返回原地址: {}", bchAddr, e);return bchAddr; // 返回原地址}}public static String trimPrefix(String address) {if (Objects.nonNull(address) && address.startsWith(MAIN_NET_PREFIX + SEPARATOR)) {address = address.substring((MAIN_NET_PREFIX + SEPARATOR).length());}return address;}
}

这里在工具类里面提供了一个 static 方法, 简化操作.

6. 测试代码

这里直接用 main 方法进行简单的测试.

// import com.google.common.base.Preconditions;// 测试方法public static void main(String[] args) {System.out.println("=== BCH 地址转换测试 ===");Map<String, String> addrPair = new HashMap<>();addrPair.put("12PJEWwWtdhg4HoHA9GHfVpMegan9BLkAJ", "bitcoincash:qq8jl2vst9vc806d83aj2px3mv2uwn620q5neyc2h7");addrPair.put("1DWWAECwYtLY8haDbC3TG3fK97q1vQ33xT", "bitcoincash:qzynt6wqpy6m3f2ykr7h7l7tvh2g9dkmgqfhqwe6t8");addrPair.put("1DPhegLSDwDFJnHkLNsNBJK8LoGEdvXyLZ", "qzr7e97ewejw3vzneuej4w74ldwgw5y9ay8m0ylk24");//for (String legacy : addrPair.keySet()) {String cashAddr = addrPair.get(legacy);System.out.println("==============");System.out.println("legacy=" + legacy);System.out.println("cashed=" + cashAddr);Preconditions.checkArgument(!legacy.equalsIgnoreCase(cashAddr));System.out.println("legacy.isValidCashAddress: " + CashAddr.isValidCashAddress(legacy));System.out.println("cashAddr.isValidCashAddress: " + CashAddr.isValidCashAddress(cashAddr));String cach2 = toAnoAddr(legacy);System.out.println("从legacy转换得到的cach2=" + cach2);Preconditions.checkArgument(!legacy.equalsIgnoreCase(cach2));Preconditions.checkArgument(trimPrefix(cashAddr).equalsIgnoreCase(trimPrefix(cach2)));String anoBtcAddr = toAnoAddr(cashAddr);System.out.println("从cashAddr转换得到的another=" + anoBtcAddr);// 判断Preconditions.checkArgument(!cashAddr.equalsIgnoreCase(anoBtcAddr));Preconditions.checkArgument(legacy.equalsIgnoreCase(anoBtcAddr));//String btcAddr2 = toAnoAddr(trimPrefix(cashAddr));System.out.println("从cashAddr.trim转换得到的btcAddr2=" + btcAddr2);// 判断相等Preconditions.checkArgument(legacy.equalsIgnoreCase(btcAddr2));}}

这里使用了一个 Preconditions 来进行检查, 如果比对不通过的话，则会抛出异常。
如果使用单测的话，可以用Assert相关类来验证转换前后的地址是否一致。

7.类库依赖

当然，也包含上文的 LTC 相关的逻辑，此处不再列出。

本文参考的代码为:

https://github.com/Electron-Cash/Electron-Cash-Java/blob/master/CashAddr.java

如果不想引入依赖，可以将这个类抽到自己的项目中，稍微定制一下即可。

对应的 CashAddr 代码修改后变成:

import java.math.BigInteger;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;// see: https://github.com/Electron-Cash/Electron-Cash-Java/blob/master/CashAddr.javapublic class CashAddr {public static final String SEPARATOR = ":";public static final String MAIN_NET_PREFIX = "bitcoincash";private static final BigInteger[] POLYMOD_GENERATORS = new BigInteger[]{new BigInteger("98f2bc8e61", 16),new BigInteger("79b76d99e2", 16), new BigInteger("f33e5fb3c4", 16), new BigInteger("ae2eabe2a8", 16),new BigInteger("1e4f43e470", 16)};private static final BigInteger POLYMOD_AND_CONSTANT = new BigInteger("07ffffffff", 16);public static final String CHARSET_BASE32 = "qpzry9x8gf2tvdw0s3jn54khce6mua7l";private static final char[] CHARS_BASE32 = CHARSET_BASE32.toCharArray();private static Map<Character, Integer> char_Base32_PositionMap;static {char_Base32_PositionMap = new HashMap<>();for (int i = 0; i < CHARS_BASE32.length; i++) {char_Base32_PositionMap.put(CHARS_BASE32[i], i);}if (char_Base32_PositionMap.size() != 32) {throw new RuntimeException("The charset must contain 32 unique characters.");}}// 解析 bch 前缀地址public static BitcoinCashAddressDecodedParts decodeCashAddress(String bitcoinCashAddress) {if (!isValidCashAddress(bitcoinCashAddress)) {throw new RuntimeException("Address wasn't valid: " + bitcoinCashAddress);}String addrPart = bitcoinCashAddress;String prefix = MAIN_NET_PREFIX;BitcoinCashAddressDecodedParts decoded = new BitcoinCashAddressDecodedParts();String[] addressParts = bitcoinCashAddress.split(SEPARATOR);if (addressParts.length == 2) {prefix = addressParts[0];addrPart = addressParts[1];}decoded.setPrefix(prefix);byte[] addressData = decodeBase32(addrPart);addressData = Arrays.copyOfRange(addressData, 0, addressData.length - 8);addressData = convertBits(addressData, 5, 8, true);byte versionByte = addressData[0];byte[] hash = Arrays.copyOfRange(addressData, 1, addressData.length);decoded.setAddressType(getAddressTypeFromVersionByte(versionByte));decoded.setHash(hash);return decoded;}// 转换为 bch 前缀地址public static String toCashAddress(BitcoinCashAddressType addressType, byte[] hash) {String prefixString = MAIN_NET_PREFIX;byte[] prefixBytes = getPrefixBytes(prefixString);byte[] payloadBytes = concatenateByteArrays(new byte[]{addressType.getVersionByte()}, hash);payloadBytes = convertBits(payloadBytes, 8, 5, false);byte[] allChecksumInput = concatenateByteArrays(concatenateByteArrays(concatenateByteArrays(prefixBytes, new byte[]{0}), payloadBytes),new byte[]{0, 0, 0, 0, 0, 0, 0, 0});byte[] checksumBytes = calculateChecksumBytesPolymod(allChecksumInput);checksumBytes = convertBits(checksumBytes, 8, 5, true);String cashAddress = encodeBase32(concatenateByteArrays(payloadBytes, checksumBytes));return prefixString + SEPARATOR + cashAddress;}private static BitcoinCashAddressType getAddressTypeFromVersionByte(byte versionByte) {for (BitcoinCashAddressType addressType : BitcoinCashAddressType.values()) {if (addressType.getVersionByte() == versionByte) {return addressType;}}throw new RuntimeException("Unknown version byte: " + versionByte);}// 判断是否是 bch 前缀类型的地址public static boolean isValidCashAddress(String bitcoinCashAddress) {try {String prefix;if (bitcoinCashAddress.contains(SEPARATOR)) {String[] split = bitcoinCashAddress.split(SEPARATOR);prefix = split[0];bitcoinCashAddress = split[1];} else {prefix = MAIN_NET_PREFIX;}if (!isSingleCase(bitcoinCashAddress))return false;bitcoinCashAddress = bitcoinCashAddress.toLowerCase();byte[] checksumData = concatenateByteArrays(concatenateByteArrays(getPrefixBytes(prefix), new byte[]{0x00}),decodeBase32(bitcoinCashAddress));byte[] calculateChecksumBytesPolymod = calculateChecksumBytesPolymod(checksumData);return new BigInteger(calculateChecksumBytesPolymod).compareTo(BigInteger.ZERO) == 0;} catch (RuntimeException re) {return false;}}private static boolean isSingleCase(String bitcoinCashAddress) {if (bitcoinCashAddress.equals(bitcoinCashAddress.toLowerCase())) {return true;}if (bitcoinCashAddress.equals(bitcoinCashAddress.toUpperCase())) {return true;}return false;}// 计算校验和private static byte[] calculateChecksumBytesPolymod(byte[] checksumInput) {BigInteger c = BigInteger.ONE;for (int i = 0; i < checksumInput.length; i++) {byte c0 = c.shiftRight(35).byteValue();c = c.and(POLYMOD_AND_CONSTANT).shiftLeft(5).xor(new BigInteger(String.format("%02x", checksumInput[i]), 16));if ((c0 & 0x01) != 0)c = c.xor(POLYMOD_GENERATORS[0]);if ((c0 & 0x02) != 0)c = c.xor(POLYMOD_GENERATORS[1]);if ((c0 & 0x04) != 0)c = c.xor(POLYMOD_GENERATORS[2]);if ((c0 & 0x08) != 0)c = c.xor(POLYMOD_GENERATORS[3]);if ((c0 & 0x10) != 0)c = c.xor(POLYMOD_GENERATORS[4]);}byte[] checksum = c.xor(BigInteger.ONE).toByteArray();if (checksum.length == 5) {return checksum;} else {byte[] newChecksumArray = new byte[5];System.arraycopy(checksum, Math.max(0, checksum.length - 5), newChecksumArray,Math.max(0, 5 - checksum.length), Math.min(5, checksum.length));return newChecksumArray;}}private static byte[] getPrefixBytes(String prefixString) {byte[] prefixBytes = new byte[prefixString.length()];char[] charArray = prefixString.toCharArray();for (int i = 0; i < charArray.length; i++) {prefixBytes[i] = (byte) (charArray[i] & 0x1f);}return prefixBytes;}private static byte[] concatenateByteArrays(byte[] first, byte[] second) {byte[] concatenatedBytes = new byte[first.length + second.length];System.arraycopy(first, 0, concatenatedBytes, 0, first.length);System.arraycopy(second, 0, concatenatedBytes, first.length, second.length);return concatenatedBytes;}private static byte[] convertBits(byte[] bytes8Bits, int from, int to, boolean strictMode) {//Copyright (c) 2017 Pieter Wuilleint length = (int) (strictMode ? Math.floor((double) bytes8Bits.length * from / to): Math.ceil((double) bytes8Bits.length * from / to));int mask = ((1 << to) - 1) & 0xff;byte[] result = new byte[length];int index = 0;int accumulator = 0;int bits = 0;for (int i = 0; i < bytes8Bits.length; i++) {byte value = bytes8Bits[i];accumulator = (((accumulator & 0xff) << from) | (value & 0xff));bits += from;while (bits >= to) {bits -= to;result[index] = (byte) ((accumulator >> bits) & mask);++index;}}if (!strictMode) {if (bits > 0) {result[index] = (byte) ((accumulator << (to - bits)) & mask);++index;}} else {if (!(bits < from && ((accumulator << (to - bits)) & mask) == 0)) {throw new RuntimeException("Strict mode was used but input couldn't be converted without padding");}}return result;}// 转换为Base32private static String encodeBase32(byte[] byteArray) {StringBuffer sb = new StringBuffer();for (int i = 0; i < byteArray.length; i++) {int val = (int) byteArray[i];if (val < 0 || val > 31) {throw new RuntimeException("This method assumes that all bytes are only from 0-31. Was: " + val);}sb.append(CHARS_BASE32[val]);}return sb.toString();}// Base32解码private static byte[] decodeBase32(String base32String) {byte[] bytes = new byte[base32String.length()];char[] charArray = base32String.toCharArray();for (int i = 0; i < charArray.length; i++) {Integer position = char_Base32_PositionMap.get(charArray[i]);if (position == null) {throw new RuntimeException("There seems to be an invalid char: " + charArray[i]);}bytes[i] = (byte) ((int) position);}return bytes;}public enum BitcoinCashAddressType {P2PKH((byte) 0), P2SH((byte) 8);private final byte versionByte;BitcoinCashAddressType(byte versionByte) {this.versionByte = versionByte;}public byte getVersionByte() {return versionByte;}}@Data// Helper class for CashAddrpublic static class BitcoinCashAddressDecodedParts {String prefix;BitcoinCashAddressType addressType;byte[] hash;}}