java监听Erc20Token交易

最新推荐文章于 2024-03-06 12:12:40 发布

落叶无声9

最新推荐文章于 2024-03-06 12:12:40 发布

阅读量2.5k

点赞数

CC 4.0 BY-SA版权

分类专栏：以太坊文章标签： java erc20 token 以太坊交易

本文链接：https://blog.youkuaiyun.com/mongo_node/article/details/82146665

本文介绍如何使用web3j库在Java中监听以太坊上的ERC20 Token交易。通过合约封装类加载和监听交易，提供代码示例，并推荐了相关的以太坊开发教程。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

你可以在web3j库的帮助下使用java轻松监听以太坊交易，但此库无法监听Erc20 Token交易。

要监听Erc20Token交易，你必须使用在合约（token）创建时的token封装类。我假设你已经使用最少的功能部署了合约，因此你的封装类看起来像这样：

package com.bolenum.util;

import java.io.IOException;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util...;

import org.web3j.abi.EventEncoder;
import org.web3j.abi...
import org.web3j.crypto.Credentials;
import org.web3j.protocol.Web3j;
import org.web3j.protocol...;
import org.web3j.tx.Contract;
import org.web3j.tx.TransactionManager;

import rx.Observable;
import rx.functions.Func1;

...

public final class Erc20TokenWrapper extends Contract {
   

    private static final String BINARY = "contract binary key";

    private Erc20TokenWrapper(String contractAddress, Web3j web3j, Credentials credentials, BigInteger gasPrice, BigInteger gasLimit) {
        super(BINARY, contractAddress, web3j, credentials, gasPrice, gasLimit);
    }

    private Erc20TokenWrapper(String contractAddress, Web3j web3j, TransactionManager transactionManager, BigInteger gasPrice, BigInteger gasLimit) {
        super(BINARY, contractAddress, web3j, transactionManager, gasPrice, gasLimit);
    }

    public List<TransferEventResponse> getTransferEvents(TransactionReceipt transactionReceipt) {
        ...
        return responses;
    }

    public Observable<TransferEventResponse> transferEventObservable(DefaultBlockParameter startBlock, DefaultBlockParameter endBlock) {
        ...
    }

    ...

    public Uint256 balanceOf(Address _owner) throws IOException {
        Function function = new Function("balanceOf", 
                Arrays.<Type>asList(_owner), 
                Arrays.<TypeReference<?>>asList(new TypeReference<Uint256>() {}));
        return executeCallSingleValueReturn(function);
    }

    ...

    public TransactionReceipt transfer(Address _to, Uint256 _amount) throws IOException, TransactionException {
        Function function = new Function("transfer", Arrays.<Type>asList(_to, _amount), Collections.<TypeReference<?>>emptyList());
        return executeTransaction(function);
    }

    ...

    public static Erc20TokenWrapper load(String contractAddress, Web3j web3j, TransactionManager transactionManager, BigInteger gasPrice, BigInteger gasLimit) {
        return new Erc20TokenWrapper(contractAddress, web3j, transactionManager, gasPrice, gasLimit);
    }

    public static class TransferEventResponse {
   
        public Address _from;
        public Address _to;
        public Uint256 _value;
        public String _transactionHash;
    }

    ...
}

现在你必须使用这个类函数来加载合约然后监听交易。使用下面的代码加载和监听交易：

Web3j web3j = Web3j.build(new HttpService("url of your ethereum blockchain"))    
ClientTransactionManager transactionManager = new ClientTransactionManager(web3j,
                    "your deployed contract addess");
            Erc20TokenWrapper token = Erc20TokenWrapper.load("your deployed contract addess", web3j, transactionManager,
                    Contract.GAS_PRICE, Contract

最低0.47元/天解锁文章