Role-based Account Key

AccountKeyRoleBased represents a role-based key. If an account has an AccountKeyRoleBased object and the transaction type is one except account update, the validation process is done according to each roles like below:

Import necessary classes from the Web3j and kaia libraries(web3j-ext).

Create a Web3j instance with the specified BAOBAB_URL

Also, you can change the default provider. For example, using the alchemy provider.

Create a credential from private key which is the transaction role key

Gas price and gas limit settings

Set the sender address equal to the loaded credential's address

Get chain ID from the network

Set the receiver address equal to any valid address

Get the nonce for the sender's address

Set the value to transfer

Set transaction type as VALUE_TRANSFER

Create a raw transaction for value transfer

Sign the transaction

Send the signed transaction to kaia network

Recover the sender address from signed transaction and compare it to the from address

Shut down the Web3j instance

SignTxWithRoleBasedExample.java

package org.web3j.example.accountKey;

import org.web3j.tx.response.PollingTransactionReceiptProcessor;

import org.web3j.tx.response.TransactionReceiptProcessor;

import org.web3j.example.keySample;

import java.io.IOException;

import java.math.BigInteger;

import org.web3j.crypto.KlayCredentials;

import org.web3j.crypto.KlayRawTransaction;

import org.web3j.crypto.KlayTransactionEncoder;

import org.web3j.crypto.transaction.type.TxType;

import org.web3j.crypto.transaction.type.TxType.Type;

import org.web3j.protocol.core.DefaultBlockParameterName;

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

import org.web3j.protocol.http.HttpService;

import org.web3j.protocol.kaia.Web3j;

import org.web3j.protocol.kaia.core.method.response.KlayRecoverFromTransactionResponse;

import org.web3j.utils.Numeric;

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

/**

*

*/

public class SignTxWithRoleBasedExample implements keySample {

/**

*

*/

public static void run() throws Exception {

Web3j web3j = Web3j.build(new HttpService(keySample.BAOBAB_URL));

KlayCredentials credentials1 = KlayCredentials.create(keySample.ROLEBASED_KEY_transactionkey,

keySample.ROLEBASED_KEY_address);

BigInteger GAS_PRICE = BigInteger.valueOf(50000000000L);

BigInteger GAS_LIMIT = BigInteger.valueOf(6721950);

String from = credentials1.getAddress();

EthChainId EthchainId = web3j.ethChainId().send();

long chainId = EthchainId.getChainId().longValue();

String to = "0x000000000000000000000000000000000000dead";

BigInteger nonce = web3j.ethGetTransactionCount(from, DefaultBlockParameterName.LATEST).send()

.getTransactionCount();

BigInteger value = BigInteger.valueOf(100);

TxType.Type type = Type.VALUE_TRANSFER;

KlayRawTransaction raw = KlayRawTransaction.createTransaction(

type,

nonce,

GAS_PRICE,

GAS_LIMIT,

to,

value,

from);

byte[] signedMessage = KlayTransactionEncoder.signMessage(raw, chainId, credentials1);

String hexValue = Numeric.toHexString(signedMessage);

EthSendTransaction transactionResponse = web3j.ethSendRawTransaction(hexValue).send();

System.out.println("TxHash : \n " + transactionResponse.getResult());

String blockNumber = "latest";

KlayRecoverFromTransactionResponse response = web3j.klayRecoverFromTransaction(hexValue, blockNumber)

.send();

System.out.println("Original address : " + from);

System.out.println("Result address : " + response.getResult());

web3j.shutdown();

}

}

output

❯ java SignTxWithRoleBasedExample.java

TxHash :

0x75b1fbfcaeb0c3fa7a0738e628a010b85b6514394ed08d25df4b055aef7d0e58

Original address : 0x5bd2fb3c21564c023a4a735935a2b7a238c4ccea

Result address : 0x5bd2fb3c21564c023a4a735935a2b7a238c4ccea