en

去中心化交易所

JuChain 提供了一套基于 Uniswap V2 模型的去中心化交易所（DEX）功能，允许用户进行代币兑换（Swap）和提供流动性（Liquidity）。

主网信息

  • 网络：JuChain 主网

  • 合约地址：0x49E5c7f25711abe668F404307b27f4bE4836B0e7

  • 部署地址：0x7389F1B4717F5152B6Cc107bce4A42a11dC0b76E

  • 更新价格地址：0xa6F32fe2920AcF559699825AFaC493aa4F49Ac1D

  • 合约权限地址：0x5021A15FaAFEFEC1daCB1c8b24FFE3F3E3f7277b

测试网信息

核心组件:

  • 路由器 (JUV2Router02): 用户交互的主要入口合约，用于执行 Swap、添加/移除流动性。与 Uniswap V2 Router 类似。

  • 工厂 (JUV2Factory): 创建和管理交易对合约。

  • 交易对 (JUV2Pair): 代表一个特定的代币交易对（例如 WJU-USDT），持有流动性资金池，并作为 ERC20 LP 代币。

  • WJU (Wrapped JU): 原生 JU 代币的 ERC20 封装版本，用于与 DEX 交互。

  • USDT: 网络上的一个示例 ERC20 代币。

1. 前置准备与网络设置

  • 主网:

    • RPC URL: https://rpc.juchain.org

    • 链 ID (Chain ID): 202599

    • 区块浏览器: https://juscan.io

  • 测试网:

    • RPC URL: https://testnet-rpc.juchain.org

    • 链 ID (Chain ID): 202599

    • 区块浏览器: https://testnet.juscan.io

  • 工具:

    • Node.js 环境及 Web3.js 库 (const { Web3 } = require('web3');) 或类似库 (ethers.js)。

    • Solidity 开发环境 (可选，用于合约交互或理解)。

  • 账户与凭证:

    • 一个外部账户 (EOA) 地址 (USER_ADDRESS)。

    • 该账户的私钥 (PRIVATE_KEY)，必须安全存储和管理，切勿硬编码或公开。

    • 账户需持有原生 JU (用于支付 Gas) 和交互所需的代币 (如 WJU, USDT)。

  • 基础设置:

    • 初始化 Web3 实例: const web3 = new Web3(RPC_URL);

    • 创建合约实例: 使用相应的 ABI (见第 7 节) 和合约地址为 WJU, USDT, Router, Factory 创建 Web3 Contract 对象。Pair 合约实例通常在获取其地址后动态创建。

2. 核心合约地址与详情

主网合约地址

合约
地址
说明

WJU

0x4d1B49B424afd7075d3c063adDf97D5575E1c7E2

封装版 JU。deposit() (payable) 封装, withdraw() 解封装。18 位小数。

USDT

0xc8e19C19479a866142B42fB390F2ea1Ff082E0D2

标准 ERC20 代币。通常为 18 位小数 (请以链上 decimals() 确认)。

工厂 (Factory)

0xCcbcecDd7d8D115Df79fc85847F38F9A5965326c

部署并追踪 JUV2Pair 交易对合约。

路由器 (Router)

0x09f58Aa3C7A8101062855C66E43a83920EB23511

交互主入口。内部将 WJU 地址视为其 WETH 地址 (router.WETH() 可验证)。

交易对初始化哈希

0x2d5d6553271f0bbe36b13a3628f44898e95763f6f3692c2de666389cb179309b

用于确定性计算交易对地址 (配合 create2)。

测试网合约地址

合约
地址
说明

WJU

0x2c67A8Ee92C5dD55b1D133631a32451e123Be1d3

封装版 JU。deposit() (payable) 封装, withdraw() 解封装。18 位小数。

USDT

0xf173cD2DD28f94F6b7F6B0817E498fe842bC5D02

标准 ERC20 代币。通常为 18 位小数 (请以链上 decimals() 确认)。

工厂 (Factory)

0x66682281BdfeC17fCBcae0480C77edFb0c489339

部署并追踪 JUV2Pair 交易对合约。

路由器 (Router)

0x6A647E09193a130b0CccBF26A1CF442491bDeCc0

交互主入口。内部将 WJU 地址视为其 WETH 地址 (router.WETH() 可验证)。

交易对初始化哈希

0x2d5d6553271f0bbe36b13a3628f44898e95763f6f3692c2de666389cb179309b

用于确定性计算交易对地址 (配合 create2)。

关键配置: 路由器合约 (JUV2Router02) 中的 WETH 地址必须指向 JuChain 上的 WJU 地址 (0x2c67A8Ee92C5dD55b1D133631a32451e123Be1d3)。这使得路由器中带有 ETH 后缀的函数能够正确处理 WJU。

3. 与 WJU 交互 (封装/解封装)

将原生 JU 转换为 ERC20 兼容的 WJU 是与 DEX 交互的前提。

  • 封装 JU (Wrap): 调用 WJU 合约的 deposit() payable 函数。

    • 操作: 构造一个发往 WJU 合约地址的交易，调用 deposit() (ABI 中提供)，并在交易中附带 value 字段，其值为您希望封装的原生 JU 数量 (单位: Wei)。

  • 解封装 WJU (Unwrap): 调用 WJU 合约的 withdraw(uint256 wad) 函数。

    • 操作: 调用 withdraw 函数，传入参数 wad 为您希望解封装换回原生 JU 的 WJU 数量 (单位: Wei)。此交易不附带 value。

4. Swap (兑换) 功能 (使用路由器)

通过路由器合约，利用已存在的流动性池进行代币兑换。

常用 Swap 函数:

  • swapExactETHForTokens: 用 精确数量 的 WJU 兑换 至少 某个数量的 ERC20 代币。

  • swapExactTokensForETH: 用 精确数量 的 ERC20 代币 兑换 至少 某个数量的 WJU。

  • swapExactTokensForTokens: 用 精确数量 的输入 ERC20 代币，兑换 至少 某个数量的输出 ERC20 代币。

核心参数:

  • amountIn / amountOut: 涉及的数量。

  • amountOutMin / amountInMax: 滑点控制，保证收到的不少于/付出的不多于此值。

  • path: 地址数组，定义兑换路径，如 [WJU_ADDRESS, USDT_ADDRESS] 或 [USDT_ADDRESS, WJU_ADDRESS]。

  • to: 接收代币的地址。

  • deadline: Unix 时间戳，交易在此时间之后失效。

流程: 使用 WJU 兑换 USDT (调用 swapExactETHForTokens)

  1. 确定输入: 决定要花费的精确 WJU 数量 (wjuAmountIn，单位 Wei)。

  2. 计算最小输出 (滑点控制):

    • 调用路由器的 getAmountsOut(wjuAmountIn, [WJU_ADDRESS, USDT_ADDRESS]) 视图函数，获取预期的 USDT 输出量 expectedUsdtAmount。

    • 根据可接受的滑点百分比 (e.g., 1% or 0.01) 计算 usdtAmountOutMin = expectedUsdtAmount * (1 - slippageTolerance)。注意： 处理大数运算时需使用 BigInt。

  3. 准备交易:

    • 设置 deadline (例如，当前时间 + 10 分钟)。

    • 构造 swapExactETHForTokens 函数调用，参数为：usdtAmountOutMin, path = [WJU_ADDRESS, USDT_ADDRESS], to = USER_ADDRESS, deadline。

  4. 发送交易:

    • 对构造好的交易进行签名 (使用 PRIVATE_KEY)。

    • 发送交易时，必须附加 value: wjuAmountIn，因为 WJU 是通过原生代币方式传递的。

    • 建议先使用 estimateGas 估算 Gas Limit，并可适当增加冗余 (e.g., * 1.1)。

流程: 使用 USDT 兑换 WJU (调用 swapExactTokensForETH)

  1. 确定输入: 决定要花费的精确 USDT 数量 (usdtAmountIn，单位 Wei)。

  2. 批准 Router:

    • 调用 USDT 合约 的 approve(ROUTER_ADDRESS, usdtAmountIn) 函数。

    • 必须等待此批准交易成功确认后才能进行下一步。

    • 优化: 可先调用 usdtContract.methods.allowance(USER_ADDRESS, ROUTER_ADDRESS) 检查现有额度，若足够则跳过批准。

  3. 计算最小输出 (滑点控制):

    • 调用路由器的 getAmountsOut(usdtAmountIn, [USDT_ADDRESS, WJU_ADDRESS]) 获取预期的 WJU 输出量 expectedWjuAmount。

    • 计算 wjuAmountOutMin = expectedWjuAmount * (1 - slippageTolerance)。

  4. 准备交易:

    • 设置 deadline。

    • 构造 swapExactTokensForETH 函数调用，参数为：usdtAmountIn, wjuAmountOutMin, path = [USDT_ADDRESS, WJU_ADDRESS], to = USER_ADDRESS, deadline。

  5. 发送交易:

    • 签名并发送交易。

    • 此交易不附加 value。

    • 同样建议估算 Gas。

Swap 注意事项:

  • 滑点: amountOutMin/amountInMax 是防止价格不利变动的重要保护措施。

  • Gas: 所有写操作都需要 Gas (原生 JU)。

  • Deadline: 防止交易卡在交易池中过久而导致执行时价格与预期偏差过大。

  • 路径 (path): 确保路径正确，对于复杂兑换可能需要经过 WJU 作为中间路由。

5. 流动性管理 (使用路由器)

向交易对提供流动性以赚取交易手续费，并获得代表份额的 LP 代币。

常用流动性函数:

  • addLiquidityETH: 添加 WJU 和一种 ERC20 代币的流动性。

  • removeLiquidityETH: 移除 WJU 和一种 ERC20 代币的流动性。

  • addLiquidity: 添加两种 ERC20 代币的流动性。

  • removeLiquidity: 移除两种 ERC20 代币的流动性。

流程: 添加 WJU-USDT 流动性 (调用 addLiquidityETH)

  1. 确定期望数量: 决定期望提供的 WJU 数量 (wjuAmountDesired) 和 USDT 数量 (usdtAmountDesired)。注意：实际添加比例将由当前池子决定，您提供的数量只是上限和期望比例。

  2. 计算最小接受数量 (滑点控制): 根据可接受的滑点计算 wjuAmountMin 和 usdtAmountMin。

  3. 检查余额: 确保账户中有足够的 WJU (通过 value 提供) 和 USDT。

  4. 批准 Router (针对 USDT):

    • 调用 USDT 合约 的 approve(ROUTER_ADDRESS, usdtAmountDesired) 函数。

    • 等待批准交易确认。

    • 优化: 可先检查 allowance，若足够则跳过。

  5. 准备交易:

    • 设置 deadline。

    • 构造 addLiquidityETH 函数调用，参数为：token = USDT_ADDRESS, amountTokenDesired = usdtAmountDesired, amountTokenMin = usdtAmountMin, amountETHMin = wjuAmountMin, to = USER_ADDRESS, deadline。

  6. 发送交易:

    • 签名并发送交易。

    • 必须附加 value: wjuAmountDesired 来提供 WJU。

    • 建议估算 Gas。交易成功后，USER_ADDRESS 会收到 WJU-USDT 的 LP 代币。

流程: 移除 WJU-USDT 流动性 (调用 removeLiquidityETH)

  1. 确定移除数量: 决定要移除的 LP 代币数量 (liquidityAmount，单位 Wei)。LP 代币通常也是 18 位小数。

  2. 计算最小取回数量 (滑点控制): 根据当前池子比例和可接受滑点，估算最少能取回的 WJU 数量 (wjuAmountMin) 和 USDT 数量 (usdtAmountMin)。可以通过查询 Pair 合约的 getReserves 和 LP 代币的 totalSupply 来辅助计算。

  3. 获取 Pair 地址: 调用 factoryContract.methods.getPair(WJU_ADDRESS, USDT_ADDRESS) 获取 WJU-USDT 的 Pair 合约地址 (pairAddress)。

  4. 批准 Router (针对 LP 代币):

    • 创建 Pair 合约实例: const pairContract = new web3.eth.Contract(ABIs.JUV2PAIR_ABI, pairAddress);

    • 调用 Pair 合约 的 approve(ROUTER_ADDRESS, liquidityAmount) 函数。

    • 等待批准交易确认。

  5. 准备交易:

    • 设置 deadline。

    • 构造 removeLiquidityETH 函数调用，参数为：token = USDT_ADDRESS, liquidity = liquidityAmount, amountTokenMin = usdtAmountMin, amountETHMin = wjuAmountMin, to = USER_ADDRESS, deadline。

  6. 发送交易:

    • 签名并发送交易。

    • 此交易不附加 value。

    • 建议估算 Gas。交易成功后，USER_ADDRESS 会收到 WJU 和 USDT。

流动性管理注意事项:

  • 无常损失: 提供流动性的固有风险，当代币相对价格变动时可能发生。

  • LP 代币: LP 代币本身也是 ERC20，可以转移或用于其他 DeFi 协议 (如果支持)。

  • 首次添加: 如果是第一个提供者，将设定初始汇率。

6. 使用工厂 (Factory)

工厂合约主要用于创建和查询交易对。

  • 查询交易对地址:

    • 调用 getPair(address tokenA, address tokenB)。

    • 如果返回非零地址，则交易对已存在。

    • 如果返回 0x000...000，则交易对不存在。

  • 创建交易对:

    • 如果通过 getPair 确认交易对不存在，可以调用 createPair(address tokenA, address tokenB)。

    • tokenA 和 tokenB 地址无序。

    • 工厂会使用 create2 部署新的 Pair 合约，并发出 PairCreated 事件。

    • 通常，addLiquidity* 函数在交易对不存在时会自动调用 createPair，但手动调用可以确保其存在。

  • 获取所有交易对信息: allPairsLength() 和 allPairs(uint index) 可用，但遍历可能成本较高。

  • 确定性计算交易对地址: 使用 pairFor 逻辑 (参见下方 Solidity 示例)，结合工厂地址、排序后的 Token 地址和 initCodeHash，可以在链下预先计算出交易对地址。

示例: 计算交易对地址 (Solidity 辅助库)

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

library PairUtil {
    // 计算给定工厂和代币对的交易对地址
    function pairFor(address factory, address tokenA, address tokenB) internal pure returns (address pair) {
        (address token0, address token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
        bytes32 salt = keccak256(abi.encodePacked(token0, token1));
        // JuChain DEX Pair 合约初始化代码哈希
        bytes32 initCodeHash = 0x2d5d6553271f0bbe36b13a3628f44898e95763f6f3692c2de666389cb179309b;
        pair = address(uint160(uint(keccak256(abi.encodePacked(
                hex'ff', factory, salt, initCodeHash
            )))));
    }
}

contract MyDEXInteractor {
    address constant FACTORY = 0x66682281BdfeC17fCBcae0480C77edFb0c489339;
    address constant WJU = 0x2c67A8Ee92C5dD55b1D133631a32451e123Be1d3;
    address constant USDT = 0xf173cD2DD28f94F6b7F6B0817E498fe842bC5D02;

    // 获取 WJU-USDT 交易对的预期地址
    function getWjuUsdtPairAddress() external pure returns (address) {
        return PairUtil.pairFor(FACTORY, WJU, USDT);
    }
}

7. 合约 ABI

强烈建议: 始终从 JuChain 区块浏览器 (https://testnet.juscan.io) 验证并获取指定合约地址的最新、最完整的官方 ABI。

{
  "WJU_ABI": [
    {"constant": false, "inputs": [{"name": "guy", "type": "address"}, {"name": "wad", "type": "uint256"}], "name": "approve", "outputs": [{"name": "", "type": "bool"}], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": false, "inputs": [], "name": "deposit", "outputs": [], "payable": true, "stateMutability": "payable", "type": "function"},
    {"constant": false, "inputs": [{"name": "dst", "type": "address"}, {"name": "wad", "type": "uint256"}], "name": "transfer", "outputs": [{"name": "", "type": "bool"}], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": false, "inputs": [{"name": "src", "type": "address"}, {"name": "dst", "type": "address"}, {"name": "wad", "type": "uint256"}], "name": "transferFrom", "outputs": [{"name": "", "type": "bool"}], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": false, "inputs": [{"name": "wad", "type": "uint256"}], "name": "withdraw", "outputs": [], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"payable": true, "stateMutability": "payable", "type": "fallback"},
    {"anonymous": false, "inputs": [{"indexed": true, "name": "src", "type": "address"}, {"indexed": true, "name": "guy", "type": "address"}, {"indexed": false, "name": "wad", "type": "uint256"}], "name": "Approval", "type": "event"},
    {"anonymous": false, "inputs": [{"indexed": true, "name": "src", "type": "address"}, {"indexed": true, "name": "dst", "type": "address"}, {"indexed": false, "name": "wad", "type": "uint256"}], "name": "Transfer", "type": "event"},
    {"anonymous": false, "inputs": [{"indexed": true, "name": "dst", "type": "address"}, {"indexed": false, "name": "wad", "type": "uint256"}], "name": "Deposit", "type": "event"},
    {"anonymous": false, "inputs": [{"indexed": true, "name": "src", "type": "address"}, {"indexed": false, "name": "wad", "type": "uint256"}], "name": "Withdrawal", "type": "event"},
    {"constant": true, "inputs": [{"name": "", "type": "address"}, {"name": "", "type": "address"}], "name": "allowance", "outputs": [{"name": "", "type": "uint256"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [{"name": "", "type": "address"}], "name": "balanceOf", "outputs": [{"name": "", "type": "uint256"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [], "name": "decimals", "outputs": [{"name": "", "type": "uint8"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [], "name": "name", "outputs": [{"name": "", "type": "string"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [], "name": "symbol", "outputs": [{"name": "", "type": "string"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [], "name": "totalSupply", "outputs": [{"name": "", "type": "uint256"}], "payable": false, "stateMutability": "view", "type": "function"}
  ],
  "USDT_ABI": [
    {"inputs": [], "stateMutability": "nonpayable", "type": "constructor"},
    {"anonymous": false, "inputs": [{"indexed": true, "internalType": "address", "name": "owner", "type": "address"}, {"indexed": true, "internalType": "address", "name": "spender", "type": "address"}, {"indexed": false, "internalType": "uint256", "name": "value", "type": "uint256"}], "name": "Approval", "type": "event"},
    {"anonymous": false, "inputs": [{"indexed": true, "internalType": "address", "name": "from", "type": "address"}, {"indexed": true, "internalType": "address", "name": "to", "type": "address"}, {"indexed": false, "internalType": "uint256", "name": "value", "type": "uint256"}], "name": "Transfer", "type": "event"},
    {"inputs": [{"internalType": "address", "name": "owner", "type": "address"}, {"internalType": "address", "name": "spender", "type": "address"}], "name": "allowance", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "stateMutability": "view", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "spender", "type": "address"}, {"internalType": "uint256", "name": "amount", "type": "uint256"}], "name": "approve", "outputs": [{"internalType": "bool", "name": "", "type": "bool"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "account", "type": "address"}], "name": "balanceOf", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "stateMutability": "view", "type": "function"},
    {"inputs": [], "name": "decimals", "outputs": [{"internalType": "uint8", "name": "", "type": "uint8"}], "stateMutability": "view", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "spender", "type": "address"}, {"internalType": "uint256", "name": "subtractedValue", "type": "uint256"}], "name": "decreaseAllowance", "outputs": [{"internalType": "bool", "name": "", "type": "bool"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "spender", "type": "address"}, {"internalType": "uint256", "name": "addedValue", "type": "uint256"}], "name": "increaseAllowance", "outputs": [{"internalType": "bool", "name": "", "type": "bool"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [], "name": "name", "outputs": [{"internalType": "string", "name": "", "type": "string"}], "stateMutability": "view", "type": "function"},
    {"inputs": [], "name": "symbol", "outputs": [{"internalType": "string", "name": "", "type": "string"}], "stateMutability": "view", "type": "function"},
    {"inputs": [], "name": "totalSupply", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "stateMutability": "view", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "amount", "type": "uint256"}], "name": "transfer", "outputs": [{"internalType": "bool", "name": "", "type": "bool"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "from", "type": "address"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "amount", "type": "uint256"}], "name": "transferFrom", "outputs": [{"internalType": "bool", "name": "", "type": "bool"}], "stateMutability": "nonpayable", "type": "function"}
  ],
  "FACTORY_ABI": [
    {"inputs": [{"internalType": "address", "name": "_feeToSetter", "type": "address"}], "payable": false, "stateMutability": "nonpayable", "type": "constructor"},
    {"anonymous": false, "inputs": [{"indexed": true, "internalType": "address", "name": "token0", "type": "address"}, {"indexed": true, "internalType": "address", "name": "token1", "type": "address"}, {"indexed": false, "internalType": "address", "name": "pair", "type": "address"}, {"indexed": false, "internalType": "uint256", "name": "", "type": "uint256"}], "name": "PairCreated", "type": "event"},
    {"constant": true, "inputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "name": "allPairs", "outputs": [{"internalType": "address", "name": "pair", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [], "name": "allPairsLength", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": false, "inputs": [{"internalType": "address", "name": "tokenA", "type": "address"}, {"internalType": "address", "name": "tokenB", "type": "address"}], "name": "createPair", "outputs": [{"internalType": "address", "name": "pair", "type": "address"}], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": true, "inputs": [], "name": "feeTo", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [], "name": "feeToSetter", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [{"internalType": "address", "name": "", "type": "address"}, {"internalType": "address", "name": "", "type": "address"}], "name": "getPair", "outputs": [{"internalType": "address", "name": "pair", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": false, "inputs": [{"internalType": "address", "name": "_feeTo", "type": "address"}], "name": "setFeeTo", "outputs": [], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": false, "inputs": [{"internalType": "address", "name": "_feeToSetter", "type": "address"}], "name": "setFeeToSetter", "outputs": [], "payable": false, "stateMutability": "nonpayable", "type": "function"}
  ],
  "ROUTER_ABI": [
    {"inputs": [{"internalType": "address", "name": "_factory", "type": "address"}, {"internalType": "address", "name": "_WETH", "type": "address"}], "stateMutability": "nonpayable", "type": "constructor"},
    {"stateMutability": "payable", "type": "receive"},
    {"inputs": [], "name": "WETH", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "stateMutability": "pure", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "tokenA", "type": "address"}, {"internalType": "address", "name": "tokenB", "type": "address"}, {"internalType": "uint256", "name": "amountADesired", "type": "uint256"}, {"internalType": "uint256", "name": "amountBDesired", "type": "uint256"}, {"internalType": "uint256", "name": "amountAMin", "type": "uint256"}, {"internalType": "uint256", "name": "amountBMin", "type": "uint256"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "addLiquidity", "outputs": [{"internalType": "uint256", "name": "amountA", "type": "uint256"}, {"internalType": "uint256", "name": "amountB", "type": "uint256"}, {"internalType": "uint256", "name": "liquidity", "type": "uint256"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "token", "type": "address"}, {"internalType": "uint256", "name": "amountTokenDesired", "type": "uint256"}, {"internalType": "uint256", "name": "amountTokenMin", "type": "uint256"}, {"internalType": "uint256", "name": "amountETHMin", "type": "uint256"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "addLiquidityETH", "outputs": [{"internalType": "uint256", "name": "amountToken", "type": "uint256"}, {"internalType": "uint256", "name": "amountETH", "type": "uint256"}, {"internalType": "uint256", "name": "liquidity", "type": "uint256"}], "stateMutability": "payable", "type": "function"},
    {"inputs": [], "name": "factory", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "stateMutability": "pure", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountOut", "type": "uint256"}, {"internalType": "uint256", "name": "reserveIn", "type": "uint256"}, {"internalType": "uint256", "name": "reserveOut", "type": "uint256"}], "name": "getAmountIn", "outputs": [{"internalType": "uint256", "name": "amountIn", "type": "uint256"}], "stateMutability": "pure", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountIn", "type": "uint256"}, {"internalType": "uint256", "name": "reserveIn", "type": "uint256"}, {"internalType": "uint256", "name": "reserveOut", "type": "uint256"}], "name": "getAmountOut", "outputs": [{"internalType": "uint256", "name": "amountOut", "type": "uint256"}], "stateMutability": "pure", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountOut", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}], "name": "getAmountsIn", "outputs": [{"internalType": "uint256[]", "name": "amounts", "type": "uint256[]"}], "stateMutability": "view", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountIn", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}], "name": "getAmountsOut", "outputs": [{"internalType": "uint256[]", "name": "amounts", "type": "uint256[]"}], "stateMutability": "view", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountA", "type": "uint256"}, {"internalType": "uint256", "name": "reserveA", "type": "uint256"}, {"internalType": "uint256", "name": "reserveB", "type": "uint256"}], "name": "quote", "outputs": [{"internalType": "uint256", "name": "amountB", "type": "uint256"}], "stateMutability": "pure", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "tokenA", "type": "address"}, {"internalType": "address", "name": "tokenB", "type": "address"}, {"internalType": "uint256", "name": "liquidity", "type": "uint256"}, {"internalType": "uint256", "name": "amountAMin", "type": "uint256"}, {"internalType": "uint256", "name": "amountBMin", "type": "uint256"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "removeLiquidity", "outputs": [{"internalType": "uint256", "name": "amountA", "type": "uint256"}, {"internalType": "uint256", "name": "amountB", "type": "uint256"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "token", "type": "address"}, {"internalType": "uint256", "name": "liquidity", "type": "uint256"}, {"internalType": "uint256", "name": "amountTokenMin", "type": "uint256"}, {"internalType": "uint256", "name": "amountETHMin", "type": "uint256"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "removeLiquidityETH", "outputs": [{"internalType": "uint256", "name": "amountToken", "type": "uint256"}, {"internalType": "uint256", "name": "amountETH", "type": "uint256"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "token", "type": "address"}, {"internalType": "uint256", "name": "liquidity", "type": "uint256"}, {"internalType": "uint256", "name": "amountTokenMin", "type": "uint256"}, {"internalType": "uint256", "name": "amountETHMin", "type": "uint256"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "removeLiquidityETHSupportingFeeOnTransferTokens", "outputs": [{"internalType": "uint256", "name": "amountETH", "type": "uint256"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "token", "type": "address"}, {"internalType": "uint256", "name": "liquidity", "type": "uint256"}, {"internalType": "uint256", "name": "amountTokenMin", "type": "uint256"}, {"internalType": "uint256", "name": "amountETHMin", "type": "uint256"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}, {"internalType": "bool", "name": "approveMax", "type": "bool"}, {"internalType": "uint8", "name": "v", "type": "uint8"}, {"internalType": "bytes32", "name": "r", "type": "bytes32"}, {"internalType": "bytes32", "name": "s", "type": "bytes32"}], "name": "removeLiquidityETHWithPermit", "outputs": [{"internalType": "uint256", "name": "amountToken", "type": "uint256"}, {"internalType": "uint256", "name": "amountETH", "type": "uint256"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "token", "type": "address"}, {"internalType": "uint256", "name": "liquidity", "type": "uint256"}, {"internalType": "uint256", "name": "amountTokenMin", "type": "uint256"}, {"internalType": "uint256", "name": "amountETHMin", "type": "uint256"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}, {"internalType": "bool", "name": "approveMax", "type": "bool"}, {"internalType": "uint8", "name": "v", "type": "uint8"}, {"internalType": "bytes32", "name": "r", "type": "bytes32"}, {"internalType": "bytes32", "name": "s", "type": "bytes32"}], "name": "removeLiquidityETHWithPermitSupportingFeeOnTransferTokens", "outputs": [{"internalType": "uint256", "name": "amountETH", "type": "uint256"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "address", "name": "tokenA", "type": "address"}, {"internalType": "address", "name": "tokenB", "type": "address"}, {"internalType": "uint256", "name": "liquidity", "type": "uint256"}, {"internalType": "uint256", "name": "amountAMin", "type": "uint256"}, {"internalType": "uint256", "name": "amountBMin", "type": "uint256"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}, {"internalType": "bool", "name": "approveMax", "type": "bool"}, {"internalType": "uint8", "name": "v", "type": "uint8"}, {"internalType": "bytes32", "name": "r", "type": "bytes32"}, {"internalType": "bytes32", "name": "s", "type": "bytes32"}], "name": "removeLiquidityWithPermit", "outputs": [{"internalType": "uint256", "name": "amountA", "type": "uint256"}, {"internalType": "uint256", "name": "amountB", "type": "uint256"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountIn", "type": "uint256"}, {"internalType": "uint256", "name": "amountOutMin", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "swapExactETHForTokens", "outputs": [{"internalType": "uint256[]", "name": "amounts", "type": "uint256[]"}], "stateMutability": "payable", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountOutMin", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "swapExactETHForTokensSupportingFeeOnTransferTokens", "outputs": [], "stateMutability": "payable", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountIn", "type": "uint256"}, {"internalType": "uint256", "name": "amountOutMin", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "swapExactTokensForETH", "outputs": [{"internalType": "uint256[]", "name": "amounts", "type": "uint256[]"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountIn", "type": "uint256"}, {"internalType": "uint256", "name": "amountOutMin", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "swapExactTokensForETHSupportingFeeOnTransferTokens", "outputs": [], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountIn", "type": "uint256"}, {"internalType": "uint256", "name": "amountOutMin", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "swapExactTokensForTokens", "outputs": [{"internalType": "uint256[]", "name": "amounts", "type": "uint256[]"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountIn", "type": "uint256"}, {"internalType": "uint256", "name": "amountOutMin", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "swapExactTokensForTokensSupportingFeeOnTransferTokens", "outputs": [], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountOut", "type": "uint256"}, {"internalType": "uint256", "name": "amountInMax", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "swapTokensForExactETH", "outputs": [{"internalType": "uint256[]", "name": "amounts", "type": "uint256[]"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountOut", "type": "uint256"}, {"internalType": "uint256", "name": "amountInMax", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "swapTokensForExactTokens", "outputs": [{"internalType": "uint256[]", "name": "amounts", "type": "uint256[]"}], "stateMutability": "nonpayable", "type": "function"},
    {"inputs": [{"internalType": "uint256", "name": "amountOut", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "swapETHForExactTokens", "outputs": [{"internalType": "uint256[]", "name": "amounts", "type": "uint256[]"}], "stateMutability": "payable", "type": "function"}
  ],
  "JUV2PAIR_ABI": [
    {"inputs": [], "payable": false, "stateMutability": "nonpayable", "type": "constructor"},
    {"anonymous": false, "inputs": [{"indexed": true, "internalType": "address", "name": "owner", "type": "address"}, {"indexed": true, "internalType": "address", "name": "spender", "type": "address"}, {"indexed": false, "internalType": "uint256", "name": "value", "type": "uint256"}], "name": "Approval", "type": "event"},
    {"anonymous": false, "inputs": [{"indexed": true, "internalType": "address", "name": "sender", "type": "address"}, {"indexed": false, "internalType": "uint256", "name": "amount0", "type": "uint256"}, {"indexed": false, "internalType": "uint256", "name": "amount1", "type": "uint256"}, {"indexed": true, "internalType": "address", "name": "to", "type": "address"}], "name": "Burn", "type": "event"},
    {"anonymous": false, "inputs": [{"indexed": true, "internalType": "address", "name": "sender", "type": "address"}, {"indexed": false, "internalType": "uint256", "name": "amount0", "type": "uint256"}, {"indexed": false, "internalType": "uint256", "name": "amount1", "type": "uint256"}], "name": "Mint", "type": "event"},
    {"anonymous": false, "inputs": [{"indexed": true, "internalType": "address", "name": "sender", "type": "address"}, {"indexed": false, "internalType": "uint256", "name": "amount0In", "type": "uint256"}, {"indexed": false, "internalType": "uint256", "name": "amount1In", "type": "uint256"}, {"indexed": false, "internalType": "uint256", "name": "amount0Out", "type": "uint256"}, {"indexed": false, "internalType": "uint256", "name": "amount1Out", "type": "uint256"}, {"indexed": true, "internalType": "address", "name": "to", "type": "address"}], "name": "Swap", "type": "event"},
    {"anonymous": false, "inputs": [{"indexed": false, "internalType": "uint112", "name": "reserve0", "type": "uint112"}, {"indexed": false, "internalType": "uint112", "name": "reserve1", "type": "uint112"}], "name": "Sync", "type": "event"},
    {"anonymous": false, "inputs": [{"indexed": true, "internalType": "address", "name": "from", "type": "address"}, {"indexed": true, "internalType": "address", "name": "to", "type": "address"}, {"indexed": false, "internalType": "uint256", "name": "value", "type": "uint256"}], "name": "Transfer", "type": "event"},
    {"constant": true, "inputs": [], "name": "DOMAIN_SEPARATOR", "outputs": [{"internalType": "bytes32", "name": "", "type": "bytes32"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [], "name": "MINIMUM_LIQUIDITY", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "payable": false, "stateMutability": "pure", "type": "function"},
    {"constant": true, "inputs": [], "name": "PERMIT_TYPEHASH", "outputs": [{"internalType": "bytes32", "name": "", "type": "bytes32"}], "payable": false, "stateMutability": "pure", "type": "function"},
    {"constant": true, "inputs": [{"internalType": "address", "name": "owner", "type": "address"}, {"internalType": "address", "name": "spender", "type": "address"}], "name": "allowance", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": false, "inputs": [{"internalType": "address", "name": "spender", "type": "address"}, {"internalType": "uint256", "name": "value", "type": "uint256"}], "name": "approve", "outputs": [{"internalType": "bool", "name": "", "type": "bool"}], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": true, "inputs": [{"internalType": "address", "name": "owner", "type": "address"}], "name": "balanceOf", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": false, "inputs": [{"internalType": "address", "name": "to", "type": "address"}], "name": "burn", "outputs": [{"internalType": "uint256", "name": "amount0", "type": "uint256"}, {"internalType": "uint256", "name": "amount1", "type": "uint256"}], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": true, "inputs": [], "name": "decimals", "outputs": [{"internalType": "uint8", "name": "", "type": "uint8"}], "payable": false, "stateMutability": "pure", "type": "function"},
    {"constant": true, "inputs": [], "name": "factory", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [], "name": "getReserves", "outputs": [{"internalType": "uint112", "name": "_reserve0", "type": "uint112"}, {"internalType": "uint112", "name": "_reserve1", "type": "uint112"}, {"internalType": "uint32", "name": "_blockTimestampLast", "type": "uint32"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": false, "inputs": [{"internalType": "address", "name": "_token0", "type": "address"}, {"internalType": "address", "name": "_token1", "type": "address"}], "name": "initialize", "outputs": [], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": true, "inputs": [], "name": "kLast", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": false, "inputs": [{"internalType": "address", "name": "to", "type": "address"}], "name": "mint", "outputs": [{"internalType": "uint256", "name": "liquidity", "type": "uint256"}], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": true, "inputs": [], "name": "name", "outputs": [{"internalType": "string", "name": "", "type": "string"}], "payable": false, "stateMutability": "pure", "type": "function"},
    {"constant": true, "inputs": [{"internalType": "address", "name": "owner", "type": "address"}], "name": "nonces", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": false, "inputs": [{"internalType": "address", "name": "owner", "type": "address"}, {"internalType": "address", "name": "spender", "type": "address"}, {"internalType": "uint256", "name": "value", "type": "uint256"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}, {"internalType": "uint8", "name": "v", "type": "uint8"}, {"internalType": "bytes32", "name": "r", "type": "bytes32"}, {"internalType": "bytes32", "name": "s", "type": "bytes32"}], "name": "permit", "outputs": [], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": true, "inputs": [], "name": "price0CumulativeLast", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [], "name": "price1CumulativeLast", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": false, "inputs": [{"internalType": "address", "name": "to", "type": "address"}], "name": "skim", "outputs": [], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": false, "inputs": [{"internalType": "uint256", "name": "amount0Out", "type": "uint256"}, {"internalType": "uint256", "name": "amount1Out", "type": "uint256"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "bytes", "name": "data", "type": "bytes"}], "name": "swap", "outputs": [], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": true, "inputs": [], "name": "symbol", "outputs": [{"internalType": "string", "name": "", "type": "string"}], "payable": false, "stateMutability": "pure", "type": "function"},
    {"constant": false, "inputs": [], "name": "sync", "outputs": [], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": true, "inputs": [], "name": "token0", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [], "name": "token1", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": true, "inputs": [], "name": "totalSupply", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "payable": false, "stateMutability": "view", "type": "function"},
    {"constant": false, "inputs": [{"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "value", "type": "uint256"}], "name": "transfer", "outputs": [{"internalType": "bool", "name": "", "type": "bool"}], "payable": false, "stateMutability": "nonpayable", "type": "function"},
    {"constant": false, "inputs": [{"internalType": "address", "name": "from", "type": "address"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "value", "type": "uint256"}], "name": "transferFrom", "outputs": [{"internalType": "bool", "name": "", "type": "bool"}], "payable": false, "stateMutability": "nonpayable", "type": "function"}
  ]
}

交互最佳实践 (参考实现体现):

  • 交易发送封装: 使用辅助函数处理 nonce 获取、gas price 设置、交易签名 (web3.eth.accounts.signTransaction) 和发送 (web3.eth.sendSignedTransaction)，并包含 try...catch 错误处理。

  • Gas 估算: 在发送交易前使用合约方法的 .estimateGas()，并可增加少量 buffer (e.g., 10-20%) 防止因链上状态变化导致 Gas 不足。

  • 滑点控制: 对于 Swap 和流动性操作，务必计算并使用 amount*Min 或 amount*Max 参数。

  • Approve 检查: 在执行需要花费 ERC20 代币的操作前，检查现有 allowance，避免不必要的 approve 交易。

  • Deadline: 为有时限的操作 (Swap, Liquidity) 设置合理的 deadline。

  • 大数处理: 使用 BigInt (Javascript 原生) 或 web3.utils.toWei/fromWei 以及 BN.js (Web3.js 内置) 处理代币数量。

在部署到主网或处理实际资产前，请务必在测试网上进行充分的测试。始终参考 JuChain 官方文档和区块浏览器以获取最新、最权威的信息和完整的 ABI。安全地管理您的私钥！

Previous测试网水龙头Next价格预言机

Last updated