我是一个以太坊区块链ethereum blockchain开发新手，我一直尝试执行智能合约使用MetaMask和Remix在Chrome浏览器上。

我现在正在尝试使用web3j开发并通过Java部署相同的以太坊智能合约。

但是当我尝试执行我的智能合约时，得到以下错误：error Intrinsic gas too low

Exception in thread "main" java.util.concurrent.ExecutionException: java.lang.RuntimeException: Error processing transaction request: Intrinsic gas too low

at java.util.concurrent.CompletableFuture.reportGet(Unknown Source)

at java.util.concurrent.CompletableFuture.get(Unknown Source)

at com.solartis.bc.Sample.main(Sample.java:44)

Caused by: java.lang.RuntimeException: Error processing transaction request: Intrinsic gas too low

at org.web3j.tx.ManagedTransaction.send(ManagedTransaction.java:43)

at org.web3j.tx.Contract.lambda$deployAsync$24(Contract.java:288)...

我已经通过几个方法来增加gas的值，但是不管我支付多大的值，我仍然会得到同样的错误。

有没有其他人面临同样的问题，我不知道问题在哪儿。下面附上更多细节：

ContractRunner.java

package com.solartis.bc;

public class ContractRunner {

public static void main(String args[]) throws InterruptedException, ExecutionException, IOException, CipherException, TransactionTimeoutException {

Web3j web3 = Web3j.build(new HttpService("http://xxxxxxx.westus.cloudapp.azure.com:8545/")); // defaults to http://localhost:8545/

Web3ClientVersion web3ClientVersion = web3.web3ClientVersion().sendAsync().get();

String clientVersion = web3ClientVersion.getWeb3ClientVersion();

System.out.println(clientVersion);

Credentials credentials = WalletUtils.loadCredentials("Mxxxxxxxxe", "C:\\Users\\adheep_m\\AppData\\Roaming\\Ethereum\\keystore\\UTC--2017-07-07T13-52-18.006069200Z--3b0d3fa08f0e0b3da8fe1f8ac0e05861bfdada25");

System.out.println(credentials.getAddress());

BigInteger GAS = new BigInteger("30000000");

BigInteger GAS_PRICE = new BigInteger("20");

BigInteger ETH = new BigInteger("1");

//LeisureTravelPolicyHolder contract = LeisureTravelPolicyHolder.deploy(web3,credentials,GAS,GAS_PRICE,ETH,test,test,test,test,test,test,test,test,test).get();

Token con = Token.deploy(web3,credentials,GAS,GAS_PRICE,ETH).get();

System.out.println(con.getContractAddress());

}

}

Token.sol:

pragma solidity ^0.4.0;

contract Token {

mapping (address => uint) public balances;

function Token() {

balances[msg.sender] = 1000000;

}

function transfer(address _to, uint _amount) {

if (balances[msg.sender] < _amount) {

throw;

}

balances[msg.sender] -= _amount;

balances[_to] += _amount;

}

}

Token.java:

package com.solartis.bc;

import java.math.BigInteger;

import java.util.Arrays;

import java.util.Collections;

import java.util.concurrent.Future;

import org.web3j.abi.TypeReference;

import org.web3j.abi.datatypes.Address;

import org.web3j.abi.datatypes.Function;

import org.web3j.abi.datatypes.Type;

import org.web3j.abi.datatypes.generated.Uint256;

import org.web3j.crypto.Credentials;

import org.web3j.protocol.Web3j;

import org.web3j.protocol.core.methods.response.TransactionReceipt;

import org.web3j.tx.Contract;

import org.web3j.tx.TransactionManager;

/**

* Auto generated code.

* Do not modify!

* Please use {@link org.web3j.codegen.SolidityFunctionWrapperGenerator} to update.

*

*

Generated with web3j version 2.2.1.

*/

public final class Token extends Contract {

private static final String BINARY = "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";

private Token(String contractAddress, Web3j web3j, Credentials credentials, BigInteger gasPrice, BigInteger gasLimit) {

super(BINARY, contractAddress, web3j, credentials, gasPrice, gasLimit);

}

private Token(String contractAddress, Web3j web3j, TransactionManager transactionManager, BigInteger gasPrice, BigInteger gasLimit) {

super(BINARY, contractAddress, web3j, transactionManager, gasPrice, gasLimit);

}

public Future balances(Address param0) {

Function function = new Function("balances",

Arrays.asList(param0),

Arrays.>asList(new TypeReference() {}));

return executeCallSingleValueReturnAsync(function);

}

public Future transfer(Address _to, Uint256 _amount) {

Function function = new Function("transfer", Arrays.asList(_to, _amount), Collections.>emptyList());

return executeTransactionAsync(function);

}

public static Future deploy(Web3j web3j, Credentials credentials, BigInteger gasPrice, BigInteger gasLimit, BigInteger initialWeiValue) {

return deployAsync(Token.class, web3j, credentials, gasPrice, gasLimit, BINARY, "", initialWeiValue);

}

public static Future deploy(Web3j web3j, TransactionManager transactionManager, BigInteger gasPrice, BigInteger gasLimit, BigInteger initialWeiValue) {

return deployAsync(Token.class, web3j, transactionManager, gasPrice, gasLimit, BINARY, "", initialWeiValue);

}

public static Token load(String contractAddress, Web3j web3j, Credentials credentials, BigInteger gasPrice, BigInteger gasLimit) {

return new Token(contractAddress, web3j, credentials, gasPrice, gasLimit);

}

public static Token load(String contractAddress, Web3j web3j, TransactionManager transactionManager, BigInteger gasPrice, BigInteger gasLimit) {

return new Token(contractAddress, web3j, transactionManager, gasPrice, gasLimit);

}

}

问题原因及解决

问题出现在GAS_PRICE和GAS_LIMIT不合适。Web3j有默认的GAS_PRICE和GAS_LIMIT。以下是更新后的代码：

BigInteger GAS = Contract.GAS_LIMIT;

BigInteger GAS_PRICE = Contract.GAS_PRICE;

Contract.GAS_LIMIT和Contract.GAS_PRICE被启用了，因此，使用下面的常数org.web3j.tx.gas.DefaultGasProvider来代替:

DefaultGasProvider.GAS_PRICE;

DefaultGasProvider.GAS_LIMIT;