Spring Boot项目中集成Geth与以太坊区块链进行交互操作实例

前置条件已经安装Geth并启动。
现在我们讲一下Spring Boot项目中集成Geth，然后怎么以太坊区块链进行交互操作。

1、添加依赖到工程pom.xml

<dependency>  
    <groupId>org.web3j</groupId>  
    <artifactId>core</artifactId>  
    <version>4.8.7</version>  
</dependency>
<dependency>
    <groupId>org.web3j</groupId>
    <artifactId>geth</artifactId>
    <version>4.8.7</version>
</dependency>

2、添加配置到yml文件

web3j:
#  client-address: http://192.168.99.100:8545
  client-address: http://127.0.0.1:8545
  admin-client: true
  httpTimeoutSeconds: 60000

3、ETH配置类EthConfig.java

/**
 * @author deray.wang
 * @date 2024/04/20 17:18
 */
@Configuration
public class EthConfig {
   
    @Value("${web3j.client-address}")
    private String rpc;

    @Bean
    public Web3j web3j() {
   
        OkHttpClient.Builder builder = new OkHttpClient.Builder();
        builder.connectTimeout(30*1000, TimeUnit.MILLISECONDS);
        builder.writeTimeout(30*1000, TimeUnit.MILLISECONDS);
        builder.readTimeout(30*1000, TimeUnit.MILLISECONDS);
        OkHttpClient httpClient = builder.build();
        Web3j web3j = Web3j.build(new HttpService(rpc,httpClient,false));
        return web3j;
    }

    /**
     * 初始化admin级别操作的对象
     * @return Admin
     */
    @Bean
    public Admin admin() {
   
        OkHttpClient.Builder builder = new OkHttpClient.Builder();
        builder.connectTimeout(30*1000, TimeUnit.MILLISECONDS);
        builder.writeTimeout(30*1000, TimeUnit.MILLISECONDS);
        builder.readTimeout(30*1000, TimeUnit.MILLISECONDS);
        OkHttpClient httpClient = builder.build();
        Admin admin = Admin.build(new HttpService(rpc,httpClient,false));
        return admin;
    }

    /**
     * 初始化personal级别操作的对象
     * @return Geth
     */
    @Bean
    public Geth geth() {
   
        OkHttpClient.Builder builder = new OkHttpClient.Builder();
        builder.connectTimeout(30*1000, TimeUnit.MILLISECONDS);
        builder.writeTimeout(30*1000, TimeUnit.MILLISECONDS);
        builder.readTimeout(30*1000, TimeUnit.MILLISECONDS);
        OkHttpClient httpClient = builder.build();
        Geth geth = Geth.build(new HttpService(rpc,httpClient,false));
        return geth;
    }

}

4、封装两个bean：转账ETH参数类 TransferEchBean.java 和BlockchainTransaction.java

/**
 * 转账ETH参数类
 * @author
 */
@Data
@ApiModel
@ToString
public class TransferEchBean {
   


    @ApiModelProperty("fromAddr")
    private String fromAddr;

    @ApiModelProperty("密码")
    private String privateKey;

    @ApiModelProperty("toAddr")
    private String toAddr;

    @ApiModelProperty("amount")
    private BigDecimal amount;

    @ApiModelProperty("data")
    private String data;

}

/**
 * @author deray.wang
 * @date 2024/04/20 13:44
 */
@Data
public class BlockchainTransaction {
   
    private String id;
    //发送发件人ID
    private Integer fromId;
    //交易金额
    private long value;
    //收件人ID
    private Integer toId;

    private Boolean accepted;
}

5、封装操作区块链的方法 BlockchainService.java

BlockchainService.java类

/**
 * @author deray.wang
 * @date 2024/04/20 13:36
 */
public interface BlockchainService {
   

    /**
     * 获取账户的Nonce
     * @param web3j
     * @param addr
     * @return
     */
    BigInteger getAcountNonce(Web3j web3j, String addr);

    /**
     * 获取账户余额
     * @param web3j
     * @param addr
     * @return
     */
    BigDecimal getAccountBalance(Web3j web3j, String addr);

    /**
     * 查询区块内容
     * @param web3j
     * @param blockNumber
     * @return
     */
    EthBlock getBlockEthBlock(Web3j web3j, BigInteger blockNumber);

    /**
     * 创建钱包
     * @param password
     * @return
     */
    ServiceResponse newAccount(String password);

    /**
     * 地址列表
     * @return
     */
    List<String> getAllAccounts();

    /**
     * 转账ETH
     * @param web3j
     * @param fromAddr
     * @param privateKey
     * @param toAddr
     * @param amount
     * @param data
     * @return
     */
    ServiceResponse transferETHD(Web3j web3j, TransferEchBean filterBean);

    /**
     * 普通转账ETH
     * @param web3j
     * @param filterBean
     * @return
     */
    ServiceResponse tranETH(Web3j web3j, TransferEchBean filterBean