对接华为区块链代码示例

要在Java中对接华为区块链服务，首先你需要了解华为云区块链平台（如FISCO BCOS）提供的SDK，通常它们提供了Java API供开发者使用。以下是一个简单的代码示例，展示了如何使用FISCO BCOS SDK进行交易操作：

import com.hyperledger.fabric.sdk.*;
import com.hyperledger.fabric.protos.common.*;
import com.hyperledger.fabric.protos.peer.*;

public class HuaweiBlockchainExample {
    private static final String ENDPOINT = "your-bcos-url";
    private static final String CHANNEL_ID = "your-channel-id";
    private static final String USER_NAME = "your-user-name";
    private static final String PASSWD = "your-password";

    public static void main(String[] args) throws Exception {
        // 创建FabricClient实例
        FabricClient fabricClient = new FabricClient(ENDPOINT);
        
        // 加载证书
        KeyValPair[] credentials = KeyValPair.create(UserAndRole.newBuilder()
                .setUser(USER_NAME)
                .setRole(PrivilegeLevel.ENDORSER.name())
                .build(),
                PASSWD.toCharArray());

        // 设置通道
        Channel channel = fabricClient.newChannel(CHANNEL_ID);

        // 获取链码实例
        Chaincode chaincode = channel.getChaincode instantiate("your-chaincode-id", "v1.0", Collections.singletonList(credentials));

        // 准备交易数据
        Transaction proposalPayload = ProposalRequest.newBuilder()
                .setProposalType(ProposalType.ENDORSER)
                .setChaincodeId(chaincode.getName())
                .setFcn("invoke") // 要调用的链码函数名
                .setArgs(new Object[]{ "arg1", "arg2" }) // 函数参数
                .build();

        // 发送交易请求并处理响应
        Response response = fabricClient.submitTransaction(proposalPayload);
        if (response.getResult().getStatus() == Status.SUCCESS) {
            System.out.println("Transaction succeeded");
        } else {
            System.err.println("Transaction failed: " + response.getMessage());
        }

        // 关闭连接
        fabricClient.shutdown();
    }
}

注意：你需要替换上述代码中的`ENDPOINT`、`CHANNEL_ID`、`USER_NAME`、`PASSWD`以及`chaincode-id`为实际的值。此外，确保你已经安装了相应的SDK，并按照华为官方文档配置好环境。