w3kim

package com.example;

import com.klaytn.caver.Caver;
import com.klaytn.caver.crypto.KlayCredentials;
import com.klaytn.caver.methods.response.KlayLogs;
import com.klaytn.caver.methods.response.KlayTransactionReceipt;
import com.klaytn.caver.tx.SmartContract;
import com.klaytn.caver.tx.manager.TransactionManager;
import java.math.BigInteger;
import java.util.ArrayList;

w3kim

pragma solidity ^0.4.24;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP. Does not include
 * the optional functions; to access them see `ERC20Detailed`.
 */
interface IERC20 {
    function totalSupply() external view returns (uint256);

    function balanceOf(address account) external view returns (uint256);

w3kim

package com.klaytn.example.caver;

import com.klaytn.caver.Caver;
import com.klaytn.caver.crypto.KlayCredentials;
import com.klaytn.caver.fee.FeePayerManager;
import com.klaytn.caver.methods.response.KlayTransactionReceipt;
import com.klaytn.caver.tx.manager.PollingTransactionReceiptProcessor;
import com.klaytn.caver.tx.type.TxTypeFeeDelegatedValueTransfer;
import com.klaytn.caver.utils.ChainId;
import org.junit.Assert;

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    private KlayTransactionReceipt.TransactionReceipt transfer(KlayCredentials from, KlayCredentials to, BigInteger value) throws IOException {
        log.info("transfer {} KLAY [{} -> {}]", value.toString(), from.getAddress(), to.getAddress());

        BigInteger nonce = caver.klay().getTransactionCount(from.getAddress(), BLK_PARAM).send().getValue();
        TxTypeValueTransfer tx = TxTypeValueTransfer.createTransaction(
                nonce,
                GAS_PRICE,
                GAS_LIMIT,
                to.getAddress(),
                value,

w3kim

@Test
public void VTTest() throws InvalidAlgorithmParameterException, NoSuchAlgorithmException, NoSuchProviderException, IOException {
    BigInteger privKey = Keys.createEcKeyPair().getPrivateKey();
    KlayCredentials credential = KlayCredentials.create(privKey.toString(16)); // newly created credential


    KlayTransactionReceipt.TransactionReceipt receipt;

    receipt = transfer(senderCredential, credential, Convert.toPeb("0.5", Convert.Unit.KLAY).toBigInteger());
    Assert.assertNotNull(receipt);

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const Caver = require('caver-js')
const caver = new Caver('https://api.baobab.klaytn.net:8651')

const originalKey = 'original_key';
const originalAccount = caver.klay.accounts.wallet.add(originalKey);
const address = originalAccount.address;
const acct1 = caver.klay.accounts.privateKeyToAccount('key1');
const acct2 = caver.klay.accounts.privateKeyToAccount('key2');
const acct3 = caver.klay.accounts.privateKeyToAccount('key3');

w3kim

const Caver = require('caver-js');
const caver = new Caver('https://api.baobab.klaytn.net:8651');

const address = '0x{address_of_account_you_wish_to_update}';
const oldPrivateKey = '0x{effective_private_key_bound_to_the_address_above}';
const newPrivateKey = caver.klay.accounts.create().privateKey; // new private key to update

// use createAccountForUpdate
const accountForUpdate = caver.klay.accounts.createAccountForUpdate(address, newPrivateKey);
console.log('>>> about to configure ACCOUNT(address=', address, ') with the following key:', newPrivateKey)

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const Caver = require('caver-js');
const caver = new Caver('https://api.baobab.klaytn.net:8651/');

const acct = caver.klay.accounts.privateKeyToAccount('your_private_key')
caver.klay.accounts.wallet.add(acct)

// Refer to count.sol for Solidity code
const COUNT_BYTECODE = {
    "linkReferences": {},
    "object": "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",

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const Caver = require('caver-js')
const caver = new Caver('https://api.baobab.klaytn.net:8651')

const sender = caver.klay.accounts.wallet.add('your_private_key');
const recipient = 'recipient_address';

const x = async () => {
    const account = await caver.klay.getAccount(sender.address);
    const startingNonce = account.account.nonce;
    console.log(startingNonce);

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const Caver = require('caver-js');
const caver = new Caver('https://api.baobab.klaytn.net:8651/');

caver.klay.accounts.wallet.create(1);
const sender = caver.klay.accounts.wallet[0];
// if there is only one key bound to an address where last160bits(keccak(key)) === address, then the key can function as payer key
const payer = caver.klay.accounts.wallet.add('0x42605fa83957d67ca8e5c843820c72037ee5dbc6b0b2d14f9d4bd5de41b446de');

// an arbitrary contract is used
async function run() {