Deploy

Web3 SDKs support to interact with Smart Contract via contract instance, not low-level transaction.

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

Connect to the kaia blockchain using Web3j and specify the URL

Create KlayCredentials using the private key

Define gas price and gas limit for the transaction

Get the sender's address and nonce

Define contract bytecode, you can get it from compiled solidity code

Get the chain ID from the Kaia network

Initialize variables for transaction parameters

Create a raw transaction

Sign the raw transaction using KlayRawTransaction.createTransaction

Send the transaction to kaia network

Get the transaction receipt and using the transaction hash

Shut down the Web3j connection

Decode the raw transaction to get the transaction type

smartContractDeploy.java

package org.web3j.example.contracts;

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.TxTypeSmartContractDeploy;

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;

import org.web3j.tx.response.PollingTransactionReceiptProcessor;

import org.web3j.tx.response.TransactionReceiptProcessor;

import org.web3j.example.keySample;

/**

*

*/

public class DeployContractExample 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);

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 = "0x60c0604052600c60809081526b48656c6c6f20576f726c642160a01b60a05260009061002b90826100dd565b5034801561003857600080fd5b5061019c565b634e487b7160e01b600052604160045260246000fd5b600181811c9082168061006857607f821691505b60208210810361008857634e487b7160e01b600052602260045260246000fd5b50919050565b601f8211156100d857600081815260208120601f850160051c810160208610156100b55750805b601f850160051c820191505b818110156100d4578281556001016100c1565b5050505b505050565b81516001600160401b038111156100f6576100f661003e565b61010a816101048454610054565b8461008e565b602080601f83116001811461013f57600084156101275750858301515b600019600386901b1c1916600185901b1785556100d4565b600085815260208120601f198616915b8281101561016e5788860151825594840194600190910190840161014f565b508582101561018c5787850151600019600388901b60f8161c191681555b5050505050600190811b01905550565b61019a806101ab6000396000f3fe608060405234801561001057600080fd5b506004361061002b5760003560e01c8063cfae321714610030575b600080fd5b61003861004e565b60405161004591906100dc565b60405180910390f35b6000805461005b9061012a565b80601f01602080910402602001604051908101604052809291908181526020018280546100879061012a565b80156100d45780601f106100a9576101008083540402835291602001916100d4565b820191906000526020600020905b8154815290600101906020018083116100b757829003601f168201915b505050505081565b600060208083528351808285015260005b81811015610109578581018301518582016040015282016100ed565b506000604082860101526040601f19601f8301168501019250505092915050565b600181811c9082168061013e57607f821691505b60208210810361015e57634e487b7160e01b600052602260045260246000fd5b5091905056fea264697066735822122002272dad43feb87cde6d15be86d8d1af21672f2443deb524dce07ca0210d1cec64736f6c63430008120033";

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

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

String to = null;

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

BigInteger value = BigInteger.ZERO;

BigInteger codeFormat = BigInteger.ZERO;

TxType.Type type = Type.SMART_CONTRACT_DEPLOY;

KlayRawTransaction raw = KlayRawTransaction.createTransaction(

type,

nonce,

GAS_PRICE,

GAS_LIMIT,

to,

value,

from,

payload,

codeFormat);

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

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();

TxTypeSmartContractDeploy rawTransaction = TxTypeSmartContractDeploy

.decodeFromRawTransaction(signedMessage);

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

}

}

output

❯ java smartContractDeploy.java

TxHash :

0xd780119c1c48519b348a653045acf28314a6da2be43dcf76c443390f0ef32a2c

receipt :

class TransactionReceipt {

blockHash: 0xf5d6fc86cc6dd1fab6e66e4436188b62302fe8ffd36fede94d42cf62a5f99e25

blockNumber: 0x8ded0a4

codeFormat: 0x0

contractAddress: 0x81fd08cfe4c37cc85fe7a33db9d493c99852dd55

feePayer: null

feePayerSignatures: []

feeRatio: null

from: 0xa2a8854b1802d8cd5de631e690817c253d6a9153

gas: 0x66919e

effectiveGasPrice: 0x5d21dba00

gasPrice: 0xba43b7400

gasUsed: 0x3af17

humanReadable: false

key: null

input: 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

logs: []

logsBloom: 0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

nonce: 0x3c3

senderTxHash: 0xd780119c1c48519b348a653045acf28314a6da2be43dcf76c443390f0ef32a2c

signature: []

status: 0x1

txError: null

to: null

transactionHash: 0xd780119c1c48519b348a653045acf28314a6da2be43dcf76c443390f0ef32a2c

transactionIndex: 0x1

type: TxTypeSmartContractDeploy

typeInt: 40

value: 0x0

}

TxType : SMART_CONTRACT_DEPLOY