如何设计C++异常类的层次结构 业务异常分类最佳实践

std::runtime_error

std::logic_error

BusinessException

#include <stdexcept>
#include <string>
#include <vector> // 示例，可能用于携带更多上下文信息

// 定义一个通用的错误码枚举，便于分类
enum class ErrorCode {
    UnknownError = 1000,
    InvalidInput = 1001,
    NotFound = 1002,
    DatabaseError = 1003,
    NetworkError = 1004,
    PermissionDenied = 1005,
    // ... 更多业务相关的错误码
};

class BusinessException : public std::runtime_error {
public:
    // 构造函数，接受错误码和消息
    explicit BusinessException(ErrorCode code, const std::string& message)
        : std::runtime_error(message), m_errorCode(code) {}

    // 提供获取错误码的方法
    ErrorCode getErrorCode() const noexcept {
        return m_errorCode;
    }

    // 可以选择性地添加更多上下文信息，例如：
    // std::vector<std::string> getDetails() const { return m_details; }

protected:
    ErrorCode m_errorCode;
    // std::vector<std::string> m_details; // 存储额外细节
};

// 输入验证异常
class ValidationException : public BusinessException {
public:
    explicit ValidationException(ErrorCode code, const std::string& message)
        : BusinessException(code, message) {}
};

// 数据库操作异常
class DatabaseException : public BusinessException {
public:
    explicit DatabaseException(ErrorCode code, const std::string& message)
        : BusinessException(code, message) {}
};

// 用户认证/授权异常
class AuthenticationException : public BusinessException {
public:
    explicit AuthenticationException(ErrorCode code, const std::string& message)
        : BusinessException(code, message) {}
};

// 更具体的异常，例如：
class UserNotFoundException : public AuthenticationException {
public:
    explicit UserNotFoundException(const std::string& userId)
        : AuthenticationException(ErrorCode::NotFound, "User not found: " + userId) {}
};

class InvalidPasswordException : public AuthenticationException {
public:
    explicit InvalidPasswordException()
        : AuthenticationException(ErrorCode::InvalidInput, "Invalid password provided.") {}
};

catch

BusinessException

ValidationException

UserNotFoundException

std::exception

ValidationException

DatabaseException

BusinessException

UserNotFoundException

InvalidInputException

std::map<std::string, std::string>

// 带有更丰富信息的异常基类示例
class DetailedBusinessException : public std::runtime_error {
public:
    explicit DetailedBusinessException(ErrorCode code, const std::string& userMessage, const std::string& debugMessage = "")
        : std::runtime_error(userMessage),
          m_errorCode(code),
          m_userMessage(userMessage),
          m_debugMessage(debugMessage.empty() ? userMessage : debugMessage),
          m_timestamp(std::chrono::system_clock::now()) {}

    ErrorCode getErrorCode() const noexcept { return m_errorCode; }
    const std::string& getUserMessage() const noexcept { return m_userMessage; }
    const std::string& getDebugMessage() const noexcept { return m_debugMessage; }
    std::chrono::system_clock::time_point getTimestamp() const noexcept { return m_timestamp; }

    // 可以在派生类中添加更多特定上下文数据
protected:
    ErrorCode m_errorCode;
    std::string m_userMessage;
    std::string m_debugMessage;
    std::chrono::system_clock::time_point m_timestamp;
};

debugMessage

contextual data

try-catch

DatabaseConnectionError

what()

UserNotFoundException

std::optional