使用web3j工具生成java版本的智能合约-白红宇

使用web3j工具生成java版本的智能合约

阅读量：6082 次

发布时间：2019-06-20

本文共 4119 字，大约阅读时间需要 13 分钟。

这里需要使用的环境 web3j，nodejs

安装编译sol工具

$ npm install -g solc

保存为hello.sol文件到本地

pragma solidity 0.4.19;  contract hello {  function main(uint a) constant returns (uint b)       {          uint result = a * 8;          return result;      }  }

编译sol文件

$ solcjs 
     
         --optimize  --bin --abi --output-dir 
      <输出目录>
       //demo$ solcjs F:\\hello.sol   --optimize  --bin --abi --output-dir F:\\

出现这种错误

Failed to write F:\F_\hello_sol_hello.bin: Error: ENOENT: no such file or directory, open 'F:\F_\hello_sol_hello.bin'Failed to write F:\F_\hello_sol_hello.abi: Error: ENOENT: no such file or directory, open 'F:\F_\hello_sol_hello.abi'

这里有个坑，就是使用solcjs 编译智能合约文件输出到目录会有一个文件夹，这个需要手动创建，我这里输出目录到F:\\ 但是它还是要输出到F:\\F_\ 下，这里的F_文件夹需要我们创建！

编译成功,记录下bin 和 abi后缀的文件

使用web3j工具生成java版本的智能合约

web3j 命令行工具下载

$ web3j solidity generate 
     <编译的bin文件地址> 
      <编译的abi文件地址>
        -o 
       <输出目录>
         -p 
        
         //demo$ web3j solidity generate F:\F_\hello_sol_hello.bin F:\F_\hello_sol_hello.abi -o E:\etheth\src\main\java -p xyz.lihang.demo.eth.sol

　PS：使用web3j命令，需要进入网站，下载web3j-3.3.1.tar，并解压。

　　　进入目录bin下，在此目录命令行执行web3j，否则web3j bash命令不存在

生成成功

package xyz.lihang.demo.eth.sol;import java.math.BigInteger;import java.util.Arrays;import org.web3j.abi.TypeReference;import org.web3j.abi.datatypes.Function;import org.web3j.abi.datatypes.Type;import org.web3j.abi.datatypes.generated.Uint256;import org.web3j.crypto.Credentials;import org.web3j.protocol.Web3j;import org.web3j.protocol.core.RemoteCall;import org.web3j.tx.Contract;import org.web3j.tx.TransactionManager;/** * Auto generated code. * 
Do not modify! * 
Please use the web3j command line tools, * or the org.web3j.codegen.SolidityFunctionWrapperGenerator in the  * codegen module to update. * * 
Generated with web3j version 3.2.0. */public class Hello_sol_hello extends Contract {    private static final String BINARY = "60606040523415600e57600080fd5b609a8061001c6000396000f300606060405260043610603e5763ffffffff7c0100000000000000000000000000000000000000000000000000000000600035041663ab3ae25581146043575b600080fd5b3415604d57600080fd5b60566004356068565b60405190815260200160405180910390f35b600802905600a165627a7a723058200cc51f5dad45190b24189d9f8ff836d704bcebc9862cfd669e054b8c8f19f66c0029";    protected Hello_sol_hello(String contractAddress, Web3j web3j, Credentials credentials, BigInteger gasPrice, BigInteger gasLimit) {        super(BINARY, contractAddress, web3j, credentials, gasPrice, gasLimit);    }    protected Hello_sol_hello(String contractAddress, Web3j web3j, TransactionManager transactionManager, BigInteger gasPrice, BigInteger gasLimit) {        super(BINARY, contractAddress, web3j, transactionManager, gasPrice, gasLimit);    }    public RemoteCall
      
        main(BigInteger a) {        Function function = new Function("main",                 Arrays.
       
        asList(new org.web3j.abi.datatypes.generated.Uint256(a)),                 Arrays.
        
         >asList(new TypeReference
         
          () {}));        return executeRemoteCallSingleValueReturn(function, BigInteger.class);    }    public static RemoteCall
          
            deploy(Web3j web3j, Credentials credentials, BigInteger gasPrice, BigInteger gasLimit) { return deployRemoteCall(Hello_sol_hello.class, web3j, credentials, gasPrice, gasLimit, BINARY, ""); } public static RemoteCall
           
             deploy(Web3j web3j, TransactionManager transactionManager, BigInteger gasPrice, BigInteger gasLimit) { return deployRemoteCall(Hello_sol_hello.class, web3j, transactionManager, gasPrice, gasLimit, BINARY, ""); } public static Hello_sol_hello load(String contractAddress, Web3j web3j, Credentials credentials, BigInteger gasPrice, BigInteger gasLimit) { return new Hello_sol_hello(contractAddress, web3j, credentials, gasPrice, gasLimit); } public static Hello_sol_hello load(String contractAddress, Web3j web3j, TransactionManager transactionManager, BigInteger gasPrice, BigInteger gasLimit) { return new Hello_sol_hello(contractAddress, web3j, transactionManager, gasPrice, gasLimit); }}