我是区块链开发的新手。目前,我正在学习以太坊平台,这听起来是一个非常好的开始环境。我在我的 Android 应用程序上测试了 web3j 库,它运行良好。我使用以下代码连接到我的 testrpc 节点:
Web3j web3 = Web3jFactory.build(new HttpService("http://192.168.1.108:8545"));
BigInteger gasPrice = BigInteger.valueOf(20000000000L);
BigInteger gasLimit = BigInteger.valueOf(500000L);
BigInteger nonce = null;
String contractAddress="0x0dd3b0efbce5c4eba2dc9b8500ecafb0b1cec28f";
String from = "0x2d6fcee3c3435ebda9184bdddf8481a87b7d1948";
List<Type> inputParameters = new ArrayList<>();
String hash ="232131231232141231231231231232123123123";
byte[] b =Arrays.copyOfRange(new BigInteger(hash, 16).toByteArray(), 1, 33);
Type _telNumber = new Bytes32(b);
Type _publicKey = new Bytes32(b);
inputParameters.add(_telNumber);
inputParameters.add(_publicKey);
Function function = new Function("addPerson",
inputParameters,
Collections.<TypeReference<?>>emptyList());
String functionEncoder = FunctionEncoder.encode(function);
Transaction transaction = Transaction.createFunctionCallTransaction(from, nonce,gasPrice,gasLimit,contractAddress,new BigInteger("0"), functionEncoder);
try {
EthSendTransaction transactionResponse = web3.ethSendTransaction(transaction).sendAsync().get();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
上面的代码有效,我能够与智能合约交互(调用函数)。
主要问题是from参数是硬编码的(我是从 testrpc 帐户列表中获得的)。
我想要实现的目标:我想创建一个应用程序,用户可以在其中创建新的钱包(帐户),并使用它们与网络进行交易。我使用以下代码成功创建了钱包:
String filePath = Environment.getExternalStorageDirectory().toString() + "/Pictures";
Web3j web3 = Web3jFactory.build(new HttpService("http://192.168.1.108:8545"));
Web3ClientVersion web3ClientVersion = null;
try {
String fileName = WalletUtils.generateNewWalletFile("your password",new File(filePath),false);
Log.d("FILENAME",fileName);
Credentials credentials = WalletUtils.loadCredentials(
"your password",
filePath+"/"+fileName);
myAddress = credentials.getAddress();
Log.d("My address",credentials.getAddress());
} catch (CipherException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (InvalidAlgorithmParameterException e) {
e.printStackTrace();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (NoSuchProviderException e) {
e.printStackTrace();
}
下一步是什么?我应该向网络广播我的地址吗?