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Smart Contract Execution

TxTypeSmartContractExecution 使用给定数据执行智能合约。 只有当 "to "是智能合约账户时，才接受TxTypeSmartContractExecution。

从 Web3j 和 kaia 库（web3j-ext）中导入必要的类。

使用 Web3j 连接到 kaia 区块链并指定 URL

使用私钥创建发送方和付费方证书。

确定交易的gas价格和gas限额

从 credentials.getAddress() 获取发件人地址

获取发件人地址的 nonce

定义智能合约数据

从 Kaia 网络获取链 ID

为交易参数初始化变量

创建原始交易

使用 "KlayTransactionEncoder.signMessage "以**发送方的身份签署交易。

使用 "KlayTransactionEncoder.signMessageAsFeePayer "将交易签署为付费方。

向 kaia 网络发送已签署的交易

获取交易收据

关闭 Web3j 实例

解码原始交易以获取交易类型

FeeDelegatedSmartContractExecutionExample.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.TxTypeFeeDelegatedSmartContractExecution;

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 FeeDelegatedSmartContractExecutionExample implements keySample {

/**

*

*/

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();

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

.getTransactionCount();

String data = "0xcfae3217";

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

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

String to = "0xc58294ecde8fdb288fd845e7a43a56564b597bdb";

byte[] payload = Numeric.hexStringToByteArray(data);

BigInteger value = BigInteger.ZERO;

TxType.Type type = Type.FEE_DELEGATED_SMART_CONTRACT_EXECUTION;

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();

int DEFAULT_POLLING_ATTEMPTS_PER_TX_HASH = 40;

int DEFAULT_BLOCK_TIME = 1 * 1000;

long DEFAULT_POLLING_FREQUENCY = DEFAULT_BLOCK_TIME;

TransactionReceiptProcessor transactionReceiptProcessor = new PollingTransactionReceiptProcessor(web3j,

DEFAULT_POLLING_FREQUENCY, DEFAULT_POLLING_ATTEMPTS_PER_TX_HASH);

org.web3j.protocol.core.methods.response.TransactionReceipt ethReceipt = transactionReceiptProcessor

.waitForTransactionReceipt(txHash);

System.out.println("Receipt from eth_getTransactionReceipt : \n" + ethReceipt);

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

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

web3j.shutdown();

TxTypeFeeDelegatedSmartContractExecution rawTransaction = TxTypeFeeDelegatedSmartContractExecution

.decodeFromRawTransaction(signedMessage);

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

}

}

output

❯ java FeeDelegatedSmartContractExecutionExample.java

TxHash :

0x43419d6dd268fd246f82f69174b46e4b599e030feca5de4542a1b524559c0879

receipt :

class TransactionReceipt {

blockHash: 0x33376f94093970fcf54d9c87669a04046b245c59c68431afef3b3444ceada0d3

blockNumber: 0x8def1f0

codeFormat: null

contractAddress: null

feePayer: 0xcb0eb737dfda52756495a5e08a9b37aab3b271da

feePayerSignatures: [class TransactionReceiptFeePayerSignaturesInner {

V: 0x7f5

R: 0x934223d90aa3ca87b17ad1b8b9914512a58e54e337bdd28e746321b35da43b91

S: 0x2cf45437c26f6a849c142d69e5382ce142d8c1bf3115203d482e8d22eb83c164

}]

feeRatio: null

from: 0xa2a8854b1802d8cd5de631e690817c253d6a9153

gas: 0x66919e

effectiveGasPrice: 0x5d21dba00

gasPrice: 0xba43b7400

gasUsed: 0x86f3

humanReadable: null

key: null

input: 0xcfae3217

logs: []

logsBloom: 0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

nonce: 0x3cb

senderTxHash: 0x7c67092dcae6ba99682d0cac6ece60388099c198c0481c3f1cc03a6294303b61

signature: []

status: 0x1

txError: null

to: 0xc58294ecde8fdb288fd845e7a43a56564b597bdb

transactionHash: 0x43419d6dd268fd246f82f69174b46e4b599e030feca5de4542a1b524559c0879

transactionIndex: 0x0

type: TxTypeFeeDelegatedSmartContractExecution

typeInt: 49

value: 0x0

}

TxType : FEE_DELEGATED_SMART_CONTRACT_EXECUTION