web3j批量轉帳

使用web3j來鏈接geth並轉帳，基本轉帳函數能夠這樣寫：

//以太坊轉帳
    //from:轉出方帳戶
    //password:轉出方密碼
    //addrTo:收款帳戶
    //value:轉帳額
    public  String transferEth(String from,String password,String to,BigInteger value) throws  Exception
    {
        EthGetTransactionCount ethGetTransactionCount = ethClient.ethGetTransactionCount(
                from, DefaultBlockParameterName.LATEST).sendAsync().get();
        BigInteger nonce = ethGetTransactionCount.getTransactionCount();
       PersonalUnlockAccount personalUnlockAccount = ethClient.personalUnlockAccount(from,password).send();
       if (personalUnlockAccount.accountUnlocked())
        {
            BigInteger gasPrice = Contract.GAS_PRICE;
            BigInteger gasLimit = Contract.GAS_LIMIT.divide(new BigInteger("2"));
            synchronized(TestLocal.class) {
                Transaction transaction = Transaction.createEtherTransaction(from,nonce,gasPrice,gasLimit,to,value);
                EthSendTransaction transactionResponse = ethClient.ethSendTransaction(transaction).sendAsync().get();;
                if(transactionResponse.hasError()){
                    String message=transactionResponse.getError().getMessage();
                    System.out.println("transaction failed,info:"+message);
                    Utils.writeFile("F:/testErr.txt","transaction failed,info:"+message);
                    return message;
                }else{
                    String hash=transactionResponse.getTransactionHash();
                    System.out.println("transaction from "+from+" to "+to+" amount:"+value);
                    SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
                    //writeFile("transaction from "+from+" to "+to+" amount:"+value+" time:"+df.format(new Date()));
                    return  hash;
                }
            }
 
        }
        return null;
    }

上面函數中，當轉帳失敗，會將失敗結果寫入F:/testErr.txt中。

批量轉帳就是在for循環中連續調用上面這個函數進行轉帳，如今設置從addr0向addr1連續轉帳10次：

for(int i=0;i<10;i++)
{
     transferEth(addr0,"123",addr1,Convert.toWei("1", Convert.Unit.ETHER).toBigInteger());
}

先查詢addr1的餘額，有102.9110385個ether：

> web3.formwei(eth.getBalance(eth.accounts[1]))
102.9110385

運行批量轉帳函數，會發現控制檯報錯：

查詢餘額，發現只轉成功了一筆：

> web3.formwei(eth.getBalance(eth.accounts[1]))
103.9110385

查看打印的錯誤信息textErr.txt：

可見失敗了9筆交易，只有第一筆交易成功了。失敗的信息是由於有交易重複。初步判斷是nonce設置出問題了。對於單筆轉帳，nonce能夠從區塊鏈查詢到，在for循環裏，須要本身去遞增nonce。

修改transferEth函數以下：

public  String transferEthWith(String from,String password,String to,BigInteger value) throws  Exception
    {
        EthGetTransactionCount ethGetTransactionCount = ethClient.ethGetTransactionCount(
                from, DefaultBlockParameterName.LATEST).sendAsync().get();
        BigInteger nonce = ethGetTransactionCount.getTransactionCount();
        if(gNoce == null)
            gNoce = nonce;
        PersonalUnlockAccount personalUnlockAccount = ethClient.personalUnlockAccount(from,password).send();
        if (personalUnlockAccount.accountUnlocked())
        {
            BigInteger gasPrice = Contract.GAS_PRICE;
            BigInteger gasLimit = Contract.GAS_LIMIT.divide(new BigInteger("2"));
            synchronized(TestLocal.class) {
                Transaction transaction = Transaction.createEtherTransaction(from,gNoce,gasPrice,gasLimit,to,value);
                gNoce = gNoce.add(new BigInteger("1"));
                EthSendTransaction transactionResponse = ethClient.ethSendTransaction(transaction).sendAsync().get();;
                if(transactionResponse.hasError()){
                    String message=transactionResponse.getError().getMessage();
                    System.out.println("transaction failed,info:"+message);
                    Utils.writeFile("F:/testErr.txt","transaction failed,info:"+message);
                    return message;
                }else{
                    String hash=transactionResponse.getTransactionHash();
                    System.out.println("transaction from "+from+" to "+to+" amount:"+value);
                    SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
                    //writeFile("transaction from "+from+" to "+to+" amount:"+value+" time:"+df.format(new Date()));
                    return  hash;
                }
            }
 
        }
        return null;
    }

查看geth的log信息，能夠看到提交了多筆交易：

查詢addr1的帳戶餘額，從103變成113了，轉帳成功：

> web3.formwei(eth.getBalance(eth.accounts[1]))
113.9110385

分享個很受歡迎全網稀缺的互動教程：

• web3j，主要是針對java和android程序員圍繞web3j庫進行區塊鏈以太坊開發的講解。