import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
private byte[] callHash(String name, Type...parameters) throws InterruptedException, ExecutionException {

        Function function = new Function(name,
            Arrays.asList(parameters),
            Arrays.asList(new TypeReference<Bytes32>() {})
        );
        String encodedFunction = FunctionEncoder.encode(function);

        TransactionManager transactionManager = cfg.getTransactionManager(cfg.getMainAddress());
        String channelLibraryAddress = contractsProperties.getAddress().get("ChannelLibrary").toString();
        org.web3j.protocol.core.methods.response.EthCall ethCall = web3j.ethCall(
            Transaction.createEthCallTransaction(
                transactionManager.getFromAddress(), channelLibraryAddress, encodedFunction),
            DefaultBlockParameterName.LATEST)
            .sendAsync().get();

        String value = ethCall.getValue();
        List<Type> list = FunctionReturnDecoder.decode(value, function.getOutputParameters());
        return ((Bytes32) list.get(0)).getValue();
    }
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
public TransactionParams detectCurrentParams(BigInteger maxGasPrice, BigInteger maxGasLimit, FunctionCall call, BigInteger value) throws IOException {
    BigInteger nonce = getNonce();
    BigInteger blockGasLimit = web3j.ethGetBlockByNumber(DefaultBlockParameterName.LATEST, false).send().getBlock().getGasLimit();
    
    EthEstimateGas gas = web3j.ethEstimateGas(new Transaction(getFromAddress(), nonce, maxGasPrice, blockGasLimit, call.contractAddress, value, call.data)).send();
    BigInteger actualGasLimit = maxGasLimit;

    if (rpc.isFailFast()) {
        CallUtil.checkError(gas, call.toString());
    } 
    if (gas.getError() == null) {
        BigInteger amountUsed = gas.getAmountUsed();
        if (amountUsed.compareTo(maxGasLimit) >= 0) {
            throw new IllegalStateException(String.format("Estimate out of gas, used: %s, limit: %s, block limit: %s, from: %s, %s", amountUsed, maxGasLimit, blockGasLimit, getFromAddress(), call));
        }
        BigInteger estimateAmount = amountUsed.shiftLeft(1);
        if (estimateAmount.compareTo(maxGasLimit) < 0) {
            actualGasLimit = estimateAmount;
        }
    } else {
        log.warn("Transaction will fail from {}: {}", getFromAddress(), call);
    }
    EthGasPrice gasPrice = web3j.ethGasPrice().send();
    CallUtil.checkError(gasPrice);
    BigInteger actualGasPrice = gasPrice.getGasPrice();
    if (actualGasPrice.compareTo(maxGasPrice) > 0) {
        log.warn("Configured gas price is less than median. Median: {}, configured: {}", actualGasPrice, maxGasPrice);
        actualGasPrice = maxGasPrice;
    }
    return new TransactionParams(nonce, actualGasPrice, actualGasLimit);
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
@Override
public Single<String> createTransaction(Wallet from, String toAddress, BigInteger subunitAmount, BigInteger gasPrice, BigInteger gasLimit, byte[] data, String password) {
	final Web3j web3j = Web3jFactory.build(new HttpService(networkRepository.getDefaultNetwork().rpcServerUrl));

	return Single.fromCallable(() -> {
		EthGetTransactionCount ethGetTransactionCount = web3j
				.ethGetTransactionCount(from.address, DefaultBlockParameterName.LATEST)
				.send();
		return ethGetTransactionCount.getTransactionCount();
	})
	.flatMap(nonce -> accountKeystoreService.signTransaction(from, password, toAddress, subunitAmount, gasPrice, gasLimit, nonce.longValue(), data, networkRepository.getDefaultNetwork().chainId))
	.flatMap(signedMessage -> Single.fromCallable( () -> {
		EthSendTransaction raw = web3j
				.ethSendRawTransaction(Numeric.toHexString(signedMessage))
				.send();
		if (raw.hasError()) {
			throw new ServiceException(raw.getError().getMessage());
		}
		return raw.getTransactionHash();
	})).subscribeOn(Schedulers.io());
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
/**
 * Ver el saldo de una cuenta ethereum
 *
 * @param address
 * @return
 * @throws Exception
 */
public BigInteger getAddressBalance(String address) throws Exception {
    try {
        // Vamos a enviar una solicitud asíncrona usando el objecto web3j 
        EthGetBalance ethGetBalance = web3j
                .ethGetBalance(address, DefaultBlockParameterName.LATEST)
                .sendAsync()
                .get();

        // saldo en wei
        BigInteger wei = ethGetBalance.getBalance();
        return wei;
    } catch (Exception ex) {
        throw ex;
    }
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
private String callSmartContractFunction(
        Function function, String contractAddress) throws Exception {
    String encodedFunction = FunctionEncoder.encode(function);

    org.web3j.protocol.core.methods.response.EthCall response = web3j.ethCall(
            Transaction.createEthCallTransaction(
                    ALICE.getAddress(), contractAddress, encodedFunction),
            DefaultBlockParameterName.LATEST)
            .sendAsync().get();

    return response.getValue();
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
/**
 * Check that the contract deployed at the address associated with this smart contract wrapper
 * is in fact the contract you believe it is.
 *
 * <p>This method uses the
 * <a href="https://github.com/ethereum/wiki/wiki/JSON-RPC#eth_getcode">eth_getCode</a> method
 * to get the contract byte code and validates it against the byte code stored in this smart
 * contract wrapper.
 *
 * @return true if the contract is valid
 * @throws IOException if unable to connect to web3j node
 */
public boolean isValid() throws IOException {
    if (contractAddress.equals("")) {
        throw new UnsupportedOperationException(
                "Contract binary not present, you will need to regenerate your smart "
                        + "contract wrapper with web3j v2.2.0+");
    }

    EthGetCode ethGetCode = web3j
            .ethGetCode(contractAddress, DefaultBlockParameterName.LATEST)
            .send();
    if (ethGetCode.hasError()) {
        return false;
    }

    String code = Numeric.cleanHexPrefix(ethGetCode.getCode());
    // There may be multiple contracts in the Solidity bytecode, hence we only check for a
    // match with a subset
    return !code.isEmpty() && contractBinary.contains(code);
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
public static String getContractCode(Web3j web3j, String contractAddress) throws IOException {
    EthGetCode ethGetCode = web3j
        .ethGetCode(contractAddress, DefaultBlockParameterName.LATEST)
        .send();

    if (ethGetCode.hasError()) {
        throw new IllegalStateException("Failed to get code for " + contractAddress + ": " + ethGetCode.getError().getMessage());
    }

    return Numeric.cleanHexPrefix(ethGetCode.getCode());
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
public BigDecimal getBalance(String accountAddress, Convert.Unit unit) {
    try {
        BigInteger balance = web3j.ethGetBalance(accountAddress, DefaultBlockParameterName.LATEST).send().getBalance();
        return Convert.fromWei(new BigDecimal(balance), unit);
    } catch (IOException e) {
        throw Throwables.propagate(e);
    }
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
protected BigInteger getNonce() throws IOException {
    if (nonce.signum() == -1) {
        EthGetTransactionCount ethGetTransactionCount = web3j.ethGetTransactionCount(
            credentials.getAddress(), DefaultBlockParameterName.PENDING).send();

        nonce = ethGetTransactionCount.getTransactionCount();
    } else {
        nonce = nonce.add(BigInteger.ONE);
    }
    return nonce;
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
private static void startObservable() {
	logger.debug("[ETH-INFO] Starting the observable...");
	ese.newMessageEventObservable(DefaultBlockParameterName.EARLIEST, DefaultBlockParameterName.LATEST)
			.subscribe(messageEvent -> {
				logger.debug("[ETH-INFO] A new message has been posted from " + messageEvent.from + ": "
						+ messageEvent.message);
			});
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
/**
 * Returns the balance (in Wei) of the specified account address. 
 */
public static BigInteger getBalanceWei(Web3j web3j, String address) throws InterruptedException, ExecutionException {
	EthGetBalance balance = web3j
			.ethGetBalance(address, DefaultBlockParameterName.LATEST)
			.sendAsync()
			.get();

	return balance.getBalance();
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
/**
 * Return the nonce (tx count) for the specified address.
 */
public static BigInteger getNonce(Web3j web3j, String address) throws InterruptedException, ExecutionException {
	EthGetTransactionCount ethGetTransactionCount = 
			web3j.ethGetTransactionCount(address, DefaultBlockParameterName.LATEST).sendAsync().get();

	return ethGetTransactionCount.getTransactionCount();
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
private String callSmartContractFunction(
        org.web3j.abi.datatypes.Function function, String contractAddress, Wallet wallet) throws Exception {
    String encodedFunction = FunctionEncoder.encode(function);

    org.web3j.protocol.core.methods.response.EthCall response = web3j.ethCall(
            Transaction.createEthCallTransaction(wallet.address, contractAddress, encodedFunction),
            DefaultBlockParameterName.LATEST)
            .sendAsync().get();

    return response.getValue();
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
@Override
public Single<BigInteger> balanceInWei(Wallet wallet) {
	return Single.fromCallable(() -> Web3jFactory
				.build(new HttpService(networkRepository.getDefaultNetwork().rpcServerUrl, httpClient, false))
				.ethGetBalance(wallet.address, DefaultBlockParameterName.LATEST)
				.send()
				.getBalance())
               .subscribeOn(Schedulers.io());
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
public BigInteger getBalanceWei(String address) {
  try {
    EthGetBalance balanceResponse = getWeb3j().ethGetBalance(address, DefaultBlockParameterName.LATEST).sendAsync().get();
    BigInteger balance = getBalanceFix(balanceResponse);
    return balance;

    // return balanceResponse.getBalance();
  }
  catch (Exception e) {
    throw new ProcessingException("Failed to get balance for address '" + address + "'", e);
  }
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
private BigInteger getNonceFix(String address) throws Exception {
  LOG.info("Getting nonce for address " + address + " ...");

  EthGetTransactionCount txCount = getWeb3j().ethGetTransactionCount(address, DefaultBlockParameterName.LATEST).sendAsync().get();
  // TODO fix this once web3j accouts for 'bug' in testrpc
  BigInteger nonce = getTransactionCount(txCount);

  LOG.info("Successfully got nonce: " + nonce);

  return nonce;
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
public static CompletableFuture<EthSendTransaction> transferEther(String from, String to, double ethAmount) {
    return web3j.ethGetTransactionCount(from, DefaultBlockParameterName.LATEST).sendAsync()
            .thenCompose(transactionCount -> parity.ethSendTransaction(
                            Transaction.createEtherTransaction(from, transactionCount.getTransactionCount(),
                                    GAS_PRICE, GAS_LIMIT, to, toWei(ethAmount))).sendAsync()
            );
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
private List<EthLog.LogResult> createFilterForEvent(
        String encodedEventSignature, String contractAddress) throws Exception {
    EthFilter ethFilter = new EthFilter(
            DefaultBlockParameterName.EARLIEST,
            DefaultBlockParameterName.LATEST,
            contractAddress
    );

    ethFilter.addSingleTopic(encodedEventSignature);

    EthLog ethLog = web3j.ethGetLogs(ethFilter).send();
    return ethLog.getLogs();
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
private String callSmartContractFunction(
        Function function, String contractAddress) throws Exception {

    String encodedFunction = FunctionEncoder.encode(function);

    org.web3j.protocol.core.methods.response.EthCall response = web3j.ethCall(
            Transaction.createEthCallTransaction(
                    ALICE.getAddress(), contractAddress, encodedFunction),
            DefaultBlockParameterName.LATEST)
            .sendAsync().get();

    return response.getValue();
}
 

import org.web3j.protocol.core.DefaultBlockParameterName; //导入依赖的package包/类
boolean isSynced() throws Exception {
    EthSyncing ethSyncing = web3j.ethSyncing().send();
    if (ethSyncing.isSyncing()) {
        return false;
    } else {
        EthBlock ethBlock =
                web3j.ethGetBlockByNumber(DefaultBlockParameterName.LATEST, false).send();
        long timestamp = ethBlock.getBlock().getTimestamp().longValueExact() * 1000;

        return System.currentTimeMillis() - syncThreshold < timestamp;
    }
}