Web3j Transfer.sendFunds() returns Error "insufficient funds for gas * price + value"

Question

When using the web3j lib for blockchain transaction in my private test blockchain I'm currently running into the titled response error: *insufficient funds for gas * price + value*

The account from which I want to transfer some ether has a balance of 10000 ether. The gas price I logged out has a value of 18000000000 as BigInt (it's WEI?) and the gas limit is the default used from the web3j has a value of 21000.

So the question is why I getting the transaction not working?I want to transfer 10 ether for example:

TransactionReceipt transactionReceipt = Transfer.sendFunds(web3, credentials, toAccount, BigDecimal.valueOf(10.0), Convert.Unit.ETHER).send();

More details

the genesis file looks like this:

{
  "config": {
      "chainId": 9999,
      "homesteadBlock": 0,
      "eip155Block": 0,
      "eip158Block": 0,
      "byzantiumBlock": 0
   },
   "difficulty": "400",
   "gasLimit": "2100000",
   "alloc": {
      "0x9b6301bf2cfe11066dbd641f91a2b82e0783130e": { 
          "balance": "100000000000000000000000" 
      }
   }
}

The code looks like this:

// create new account 
Admin admin = Admin.build(new HttpService());
NewAccountIdentifier newAccount = admin.personalNewAccount("PASSWORD").send();

// get current created account
Web3j web3 = Web3.build(new HttpService());
EthAccounts accounts = web3.ethAccounts().send();
String lastAccount = Iterables.getLast(accounts.getAccounts());
// get creadentials for the first account having some ether
String firstAccount = web3.ethAccounts().send().getAccounts().get(0);
Credentials credentials = Credentials.create(firstAccount);

// get current balance for first account
EthGetBalance balance = admin.ethGetBalance(firstAccount, DefaultBlockParameterName.LATEST).send();
BigDecimal balanceVaue = Convert.fromWei(balance.getBalance().toString(), Convert.Unit.ETHER);

// create transaction to give the new created account some ether from the first one
// log some stuff
System.out.println("Account: " + firstAccount);
System.out.println("Account balance: " + balanceVaue);
System.out.println("Gas Price admin.ethGasPrice() in Ether: " + Convert.fromWei(gasPrice.toString(), Convert.Unit.ETHER));
System.out.println("Transfer Gas Limit in Ether: " + Convert.fromWei(Transfer.GAS_LIMIT.toString(), Convert.Unit.ETHER));
System.out.println("Transfer Gas Price in Ether: " + Convert.fromWei(Transfer.GAS_PRICE.toString(), Convert.Unit.ETHER));

TransactionReceipt transactionReceipt = Transfer.sendFunds(web3, credentials, lastAccount, BigDecimal.valueOf(10.0), Convert.Unit.ETHER).send();
String transactionHash = transactionReceipt.getTransactionHash();

This causes the above transaction error: insufficient funds for gas * price + value

Here is the logging output:

Account: 0x9b6301bf2cfe11066dbd641f91a2b82e0783130e
Account balance: 100000
Gas Price admin.ethGasPrice() in Ether: 1.8E-8
Transfer Gas Limit in Ether: 2.1E-14
Transfer Gas Price in Ether: 2.2E-8
Funds transfer triggered ...

Fibrinous

Answer 1

Your Credentials object is not correct. The method you're using is expecting the private key, not the Ethereum address.

Credentials credentials = Credentials.create(firstAccount);

should be

Credentials credentials = Credentials.create("<PRIVATE_KEY_HERE>");

Frizzly

@Fibrinous If this answer solved your question, you can indicate that by marking the answer as accepted (click the grey tick mark) – Irruptive