/**
* 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<UTXO> 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);
}