Multisig Account Key

AccountKeyWeightedMultiSig is an account key type containing a threshold and WeightedPublicKeys which contains a list consisting of a public key and its weight.

In order for a transaction to be valid for an account associated with AccountKeyWeightedMultiSig, the following conditions should be satisfied: _ The weighted sum of the signed public keys should be larger than the threshold. _ The invalid signature should not be included in the transaction. * The number of signed public keys should be less than the number of weightedPublicKeys.

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 3 multi-sig credentials from theirs key pairs

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 in order with 3 credentials

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

SignTxWithMultiSigExample.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 SignTxWithMultiSigExample implements keySample {

/**

*

*/

public static void run() throws Exception {

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

KlayCredentials credentials1 = KlayCredentials.create(keySample.MULTI_KEY_privkey1,

keySample.MULTI_KEY_address);

KlayCredentials credentials2 = KlayCredentials.create(keySample.MULTI_KEY_privkey2,

keySample.MULTI_KEY_address);

KlayCredentials credentials3 = KlayCredentials.create(keySample.MULTI_KEY_privkey3,

keySample.MULTI_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);

signedMessage = KlayTransactionEncoder.signMessage(signedMessage, chainId, credentials2);

signedMessage = KlayTransactionEncoder.signMessage(signedMessage, chainId, credentials3);

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 SignTxWithMultiSigExample.java

TxHash :

0x957734684be8f79a21cef4de1842709b84c92e3920d656165ddb951981987b5a

Original address : 0x82c6a8d94993d49cfd0c1d30f0f8caa65782cc7e

Result address : 0x82c6a8d94993d49cfd0c1d30f0f8caa65782cc7e