USDT离线签名-蒲公英云

/\*\*  
 \* usdt 离线签名  
 \*  
 \* @param privateKey：私钥  
 \* @param toAddress：接收地址  
 \* @param amount:转账金额  
 \* @return  
 \*/  
public String omniSign(String fromAddress, String toAddress, String privateKey, Long amount, Long fee, Integer propertyid, List<UTXO> utxos) throws Exception \{  
    NetworkParameters networkParameters = isMainNet ? MainNetParams.get() : TestNet3Params.get();  
    Transaction tran = new Transaction(networkParameters);  
     if(utxos==null||utxos.size()==0)\{  
         throw new Exception("utxo为空");  
     \}  
    //这是比特币的限制最小转账金额，所以很多usdt转账会收到一笔0.00000546的btc  
    Long miniBtc = 546L;  
    tran.addOutput(Coin.valueOf(miniBtc), Address.fromBase58(networkParameters, toAddress));
    //构建usdt的输出脚本 注意这里的金额是要乘10的8次方  
    String usdtHex = "6a146f6d6e69" + String.format("%016x", propertyid) + String.format("%016x", amount);  
    tran.addOutput(Coin.valueOf(0L), new Script(Utils.HEX.decode(usdtHex)));
    //如果有找零就添加找零  
    String changeAddress = fromAddress;  
    Long changeAmount = 0L;  
    Long utxoAmount = 0L;  
    List<UTXO> needUtxo = new ArrayList<>();  
    for (UTXO utxo : utxos) \{  
        if (utxoAmount > (fee + miniBtc)) \{  
            break;  
        \} else \{  
            needUtxo.add(utxo);  
            utxoAmount += utxo.getValue().value;  
        \}  
    \}  
    changeAmount = utxoAmount - (fee + miniBtc);  
    //余额判断  
    if (changeAmount < 0) \{  
        throw new Exception("utxo余额不足");  
    \}  
    if (changeAmount > 0) \{  
        tran.addOutput(Coin.valueOf(changeAmount), Address.fromBase58(networkParameters, changeAddress));  
    \}
    //先添加未签名的输入，也就是utxo  
    for (UTXO utxo : needUtxo) \{  
        tran.addInput(utxo.getHash(), utxo.getIndex(), utxo.getScript()).setSequenceNumber(TransactionInput.NO\_SEQUENCE - 2);  
    \}
    //下面就是签名  
    for (int i = 0; i < needUtxo.size(); i++) \{  
        ECKey ecKey = DumpedPrivateKey.fromBase58(networkParameters, privateKey).getKey();  
        TransactionInput transactionInput = tran.getInput(i);  
        Script scriptPubKey = ScriptBuilder.createOutputScript(Address.fromBase58(networkParameters, fromAddress));  
        Sha256Hash hash = tran.hashForSignature(i, scriptPubKey, Transaction.SigHash.ALL, false);  
        ECKey.ECDSASignature ecSig = ecKey.sign(hash);  
        TransactionSignature txSig = new TransactionSignature(ecSig, Transaction.SigHash.ALL, false);  
        transactionInput.setScriptSig(ScriptBuilder.createInputScript(txSig, ecKey));  
    \}
    //这是签名之后的原始交易，直接去广播就行了  
    String signedHex = Hex.toHexString(tran.bitcoinSerialize());  
    //这是交易的hash  
    String txHash = Hex.toHexString(Utils.reverseBytes(Sha256Hash.hash(Sha256Hash.hash(tran.bitcoinSerialize()))));  
    logger.info("fee:\{\},utxoAmount:\{\},changeAmount:\{\}", fee, utxoAmount, changeAmount);  
    return signedHex;  
\}
/\*\*  
 \* 获取矿工费用  
 \* @param utxos  
 \* @return  
 \*/  
public Long getOmniFee(List<UTXO> utxos) \{  
    Long miniBtc = 546L;  
    Long feeRate = getFeeRate();  
    Long utxoAmount = 0L;  
    Long fee = 0L;  
    Long utxoSize = 0L;  
    for (UTXO output : utxos) \{  
        utxoSize++;  
        if (utxoAmount > (fee + miniBtc)) \{  
            break;  
        \} else \{  
            utxoAmount += output.getValue().value;  
            fee = (utxoSize \* 148 \* 34 \* 3 + 10) \* feeRate;  
        \}  
    \}  
    return fee;  
\}
/\*\*\*  
 \* 获取未消费列表  
 \* @param address ：地址  
 \* @return  
 \*/  
public List<UTXO> getUnspent(String address) \{  
    List<UTXO> utxos = Lists.newArrayList();  
    String host = this.isMainNet ? "blockchain.info" : "testnet.blockchain.info";  
    String url = "https://" + host + "/zh-cn/unspent?active=" + address;  
    try \{  
        String httpGet = HttpUtil.sendGet(url, null);//TODO;联网  
        if (StringUtils.equals("No free outputs to spend", httpGet)) \{  
            return utxos;  
        \}  
        JSONObject jsonObject = JSON.parseObject(httpGet);  
        JSONArray unspentOutputs = jsonObject.getJSONArray("unspent\_outputs");  
        List<Map> outputs = JSONObject.parseArray(unspentOutputs.toJSONString(), Map.class);  
        if (outputs == null || outputs.size() == 0) \{  
            System.out.println("交易异常，余额不足");  
        \}  
        for (int i = 0; i < outputs.size(); i++) \{  
            Map outputsMap = outputs.get(i);  
            String tx\_hash = outputsMap.get("tx\_hash").toString();  
            String tx\_hash\_big\_endian = outputsMap.get("tx\_hash\_big\_endian").toString();  
            String tx\_index = outputsMap.get("tx\_index").toString();  
            String tx\_output\_n = outputsMap.get("tx\_output\_n").toString();  
            String script = outputsMap.get("script").toString();  
            String value = outputsMap.get("value").toString();  
            String value\_hex = outputsMap.get("value\_hex").toString();  
            String confirmations = outputsMap.get("confirmations").toString();  
            UTXO utxo = new UTXO(Sha256Hash.wrap(tx\_hash\_big\_endian), Long.valueOf(tx\_output\_n), Coin.valueOf(Long.valueOf(value)),  
                    0, false, new Script(Hex.decode(script)));  
            utxos.add(utxo);  
        \}  
        return utxos;  
    \} catch (Exception e) \{  
        logger.error("【BTC获取未消费列表】失败，", e);  
        return null;  
    \}
\}  
/\*\*  
 \* 获取btc费率  
 \*  
 \* @return  
 \*/  
public Long getFeeRate() \{  
    try \{  
        String httpGet1 = HttpUtil.sendGet("https://bitcoinfees.earn.com/api/v1/fees/recommended", null);  
        Map map = JSON.parseObject(httpGet1, Map.class);  
        Long fastestFee = Long.valueOf(map.get("fastestFee").toString());  
        return fastestFee;  
    \} catch (Exception e) \{  
        e.printStackTrace();  
        return 0L;  
    \}  
\}

2.测试：
@Test
public void tranaction() throws Exception {
api.setIsMainNet(false);
String fromAddress = “mm26iTQBLEga8zJxvqURo81xuKE7y4m3hB”;
String toAddress = “mjsmd3HGE7erguBCqCef2jG98TZrFLX6LY”;
String privateKey = “xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx”;
List utxos = api.getUnspent(fromAddress);
Long amount = 10000L;
Integer propertyid = 1;
Long fee = api.getOmniFee(utxos);
String sign = api.omniSign(fromAddress, toAddress, privateKey, amount,fee, propertyid,utxos);
String txid = api.publishTx(sign);//广播交易
System.out.println(txid);
}