이 페이지는 영어로 된 기계 번역을 사용하므로 오류나 불명확한 언어가 포함될 수 있습니다. 가장 정확한 정보는 영어 원문을 참조하시기 바랍니다. 잦은 업데이트로 인해 일부 콘텐츠는 원래 영어로 되어 있을 수 있습니다. Crowdin에서 이 페이지의 번역을 개선하는 데 동참하여 도움을 주세요. (Crowdin translation page, Contributing guide)

Value Transfer Memo

TxTypeValueTransferMemo is used when a user wants to send KAIA with a specific message.

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

Connect to the kaia blockchain using Web3j and specify the URL

Creating sender and fee payer credentials using private keys.

Define gas price and gas limit for the transaction

Get the sender's address from credentials.getAddress()

Get the chain ID from the Kaia network

Initialize variables for transaction parameters

Create a raw transaction object.

Signing the transaction as sender using KlayTransactionEncoder.signMessage.

Signing the transaction as fee payer using KlayTransactionEncoder.signMessageAsFeePayer.

Sending the signed transaction to kaia network

Getting the transaction receipt

Shutting down the Web3j instance

Decoding the raw transaction to get the transaction type

FeeDelegatedValueTransferMemo.java

package org.web3j.example.transactions;

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.TxTypeFeeDelegatedValueTransferMemo;

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.core.methods.response.EthSendTransaction;

import org.web3j.protocol.http.HttpService;

import org.web3j.protocol.kaia.Web3j;

import org.web3j.utils.Numeric;

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

public class FeeDelegatedValueTransferMemoExample {

public static void run() throws Exception {

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

KlayCredentials credentials = KlayCredentials.create(keySample.LEGACY_KEY_privkey);

KlayCredentials credentials_feepayer = KlayCredentials.create(keySample.LEGACY_KEY_FEEPAYER_privkey);

BigInteger GAS_PRICE = BigInteger.valueOf(50000000000L);

BigInteger GAS_LIMIT = BigInteger.valueOf(6721950);

String from = credentials.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);

String data = "Kaia Web3j";

byte[] payload = data.getBytes();

TxType.Type type = Type.FEE_DELEGATED_VALUE_TRANSFER_MEMO;

KlayRawTransaction raw = KlayRawTransaction.createTransaction(

type,

nonce,

GAS_PRICE,

GAS_LIMIT,

to,

value,

from,

payload);

// Sign as sender

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

// Sign same message as Fee payer

signedMessage = KlayTransactionEncoder.signMessageAsFeePayer(raw, chainId, credentials_feepayer);

String hexValue = Numeric.toHexString(signedMessage);

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

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

String txHash = transactionResponse.getResult();

try {

Thread.sleep(2000);

} catch (Exception e) {

System.out.println(e);

}

TransactionReceipt receipt = web3j.klayGetTransactionReceipt(txHash).send().getResult();

System.out.println("Receipt from klay_getTransactionReceipt : \n" + receipt);

web3j.shutdown();

TxTypeFeeDelegatedValueTransferMemo rawTransaction = TxTypeFeeDelegatedValueTransferMemo

.decodeFromRawTransaction(hexValue);

System.out.println("TxType : " + rawTransaction.getKlayType());

}

}

output

❯ java FeeDelegatedValueTransferMemo.java

output