@Service
public class UserService {
    
    // 錯(cuò)誤示例：事務(wù)不會(huì)生效
    @Transactional
    void createUserInternal(User user) {
        userMapper.insert(user);
        // 如果這里出現(xiàn)異常，事務(wù)不會(huì)回滾
        if (user.getAge() < 0) {
            throw new RuntimeException("年齡不能為負(fù)數(shù)");
        }
    }
    
    // 正確示例：使用public修飾符
    @Transactional
    public void createUser(User user) {
        userMapper.insert(user);
        if (user.getAge() < 0) {
            throw new RuntimeException("年齡不能為負(fù)數(shù)");
        }
    }
}

@Service
public class OrderService {
    
    @Autowired
    private OrderMapper orderMapper;
    
    public void placeOrder(Order order) {
        // 其他業(yè)務(wù)邏輯
        validateOrder(order);
        
        // 自調(diào)用 - 事務(wù)不會(huì)生效！
        createOrder(order);
        
        // 正確的調(diào)用方式
        // orderService.createOrder(order);
    }
    
    @Transactional
    public void createOrder(Order order) {
        orderMapper.insert(order);
        updateInventory(order.getItems());
        // 如果更新庫(kù)存失敗，期望訂單創(chuàng)建回滾，但自調(diào)用時(shí)不會(huì)回滾
    }
    
    private void updateInventory(List<OrderItem> items) {
        for (OrderItem item : items) {
            if (item.getQuantity() > getStock(item.getProductId())) {
                throw new RuntimeException("庫(kù)存不足");
            }
            // 更新庫(kù)存...
        }
    }
}

@Service
public class OrderService {
    
    public void placeOrder(Order order) {
        validateOrder(order);
        
        // 通過(guò)AopContext獲取代理對(duì)象
        OrderService proxy = (OrderService) AopContext.currentProxy();
        proxy.createOrder(order);
    }
    
    @Transactional
    public void createOrder(Order order) {
        // 事務(wù)操作...
    }
}

@Service
public class OrderService {
    
    @Autowired
    private OrderTransactionService orderTransactionService;
    
    public void placeOrder(Order order) {
        validateOrder(order);
        orderTransactionService.createOrder(order);
    }
}

@Service
public class OrderTransactionService {
    
    @Transactional
    public void createOrder(Order order) {
        // 事務(wù)操作...
    }
}

@Service
public class PaymentService {
    
    @Autowired
    private PaymentMapper paymentMapper;
    
    @Autowired
    private AccountService accountService;
    
    // 錯(cuò)誤示例：異常被捕獲
    @Transactional
    public void processPayment(Payment payment) {
        try {
            paymentMapper.insert(payment);
            accountService.deductBalance(payment.getUserId(), payment.getAmount());
            // 可能拋出受檢異常
            sendPaymentNotification(payment);
        } catch (Exception e) {
            // 異常被捕獲，事務(wù)不會(huì)回滾！
            log.error("支付處理失敗", e);
        }
    }
    
    // 錯(cuò)誤示例：拋出受檢異常
    @Transactional
    public void processPaymentWithCheckedException(Payment payment) throws IOException {
        paymentMapper.insert(payment);
        accountService.deductBalance(payment.getUserId(), payment.getAmount());
        
        if (payment.getAmount().compareTo(BigDecimal.ZERO) < 0) {
            // 受檢異常，默認(rèn)不會(huì)觸發(fā)回滾
            throw new IOException("支付金額不能為負(fù)數(shù)");
        }
    }
}

@Transactional
public void processPayment(Payment payment) {
    try {
        paymentMapper.insert(payment);
        accountService.deductBalance(payment.getUserId(), payment.getAmount());
        sendPaymentNotification(payment);
    } catch (Exception e) {
        log.error("支付處理失敗", e);
        // 手動(dòng)設(shè)置回滾
        TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();
        throw new RuntimeException("支付失敗", e);
    }
}

// 指定所有Exception都觸發(fā)回滾
@Transactional(rollbackFor = Exception.class)
public void processPaymentWithCheckedException(Payment payment) throws IOException {
    paymentMapper.insert(payment);
    accountService.deductBalance(payment.getUserId(), payment.getAmount());
    
    if (payment.getAmount().compareTo(BigDecimal.ZERO) < 0) {
        throw new IOException("支付金額不能為負(fù)數(shù)");
    }
}

// 更精確的控制
@Transactional(rollbackFor = {BusinessException.class, IOException.class}, 
               noRollbackFor = {ValidationException.class})
public void processPaymentWithSpecificExceptions(Payment payment) {
    // 業(yè)務(wù)邏輯...
}

@Configuration
@EnableTransactionManagement
public class TransactionConfig {
    
    @Bean
    public PlatformTransactionManager transactionManager(DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }
}

-- 檢查表使用的存儲(chǔ)引擎
SHOW TABLE STATUS LIKE 'your_table_name';

-- 修改表存儲(chǔ)引擎為InnoDB
ALTER TABLE your_table_name ENGINE=InnoDB;

-- 創(chuàng)建新表時(shí)指定存儲(chǔ)引擎
CREATE TABLE example (
    id BIGINT PRIMARY KEY AUTO_INCREMENT,
    name VARCHAR(100)
) ENGINE=InnoDB;

@Service
public class AuditService {
    
    @Autowired
    private AuditMapper auditMapper;
    
    // 錯(cuò)誤使用傳播機(jī)制
    @Transactional(propagation = Propagation.SUPPORTS)
    public void logOperation(String operation) {
        auditMapper.insert(new AuditLog(operation));
        // 如果當(dāng)前沒(méi)有事務(wù)，這個(gè)插入操作不會(huì)在事務(wù)中執(zhí)行
    }
}

@Service
public class BusinessService {
    
    @Autowired
    private AuditService auditService;
    
    @Transactional
    public void businessMethod() {
        // 主業(yè)務(wù)邏輯...
        
        // 審計(jì)日志 - 期望獨(dú)立事務(wù)，但實(shí)際使用了主事務(wù)
        auditService.logOperation("業(yè)務(wù)操作完成");
    }
}

@Service
public class AuditService {
    
    // 正確使用REQUIRES_NEW
    @Transactional(propagation = Propagation.REQUIRES_NEW)
    public void logOperationInNewTransaction(String operation) {
        auditMapper.insert(new AuditLog(operation));
        // 這個(gè)操作會(huì)在獨(dú)立的新事務(wù)中執(zhí)行
        // 即使外部事務(wù)回滾，審計(jì)日志仍然會(huì)保存
    }
    
    // 正確使用NOT_SUPPORTED
    @Transactional(propagation = Propagation.NOT_SUPPORTED)
    public void logOperationWithoutTransaction(String operation) {
        auditMapper.insert(new AuditLog(operation));
        // 這個(gè)操作會(huì)在無(wú)事務(wù)環(huán)境中執(zhí)行
    }
}

// 錯(cuò)誤示例：手動(dòng)管理Connection
@Transactional
public void updateWithManualCommit(Data data) {
    Connection conn = null;
    try {
        conn = dataSource.getConnection();
        conn.setAutoCommit(false);
        
        // 執(zhí)行SQL操作
        updateData(conn, data);
        
        // 手動(dòng)提交
        conn.commit();
    } catch (SQLException e) {
        if (conn != null) {
            conn.rollback();
        }
        throw new RuntimeException(e);
    } finally {
        if (conn != null) {
            conn.close();
        }
    }
}

@Transactional
public void updateWithSpringTransaction(Data data) {
    // 直接使用Spring管理的數(shù)據(jù)訪問(wèn)組件
    jdbcTemplate.update("UPDATE table SET column = ? WHERE id = ?", 
                       data.getValue(), data.getId());
    // Spring會(huì)自動(dòng)處理事務(wù)提交和回滾
}

@Service
public class AsyncService {
    
    @Async
    @Transactional
    public void asyncProcess(Data data) {
        // 這個(gè)事務(wù)不會(huì)生效！
        dataMapper.insert(data);
        processData(data);
    }
}

@Service
public class MainService {
    
    @Autowired
    private AsyncService asyncService;
    
    @Transactional
    public void mainProcess(Data data) {
        // 在主事務(wù)中完成核心數(shù)據(jù)操作
        dataMapper.insert(data);
        
        // 異步處理非核心業(yè)務(wù)
        asyncService.asyncProcessNonCritical(data);
    }
}

@Service
public class AsyncService {
    
    @Async
    public void asyncProcessNonCritical(Data data) {
        // 非核心的異步處理，不要求事務(wù)
        sendNotification(data);
        updateCache(data);
    }
}

@Service
public class AsyncService {
    
    @Autowired
    private TransactionTemplate transactionTemplate;
    
    @Async
    public void asyncProcessWithTransaction(Data data) {
        transactionTemplate.execute(status -> {
            // 在編程式事務(wù)中執(zhí)行
            dataMapper.insert(data);
            processData(data);
            return null;
        });
    }
}

// 錯(cuò)誤配置：沒(méi)有指定事務(wù)管理器
@Configuration
@EnableTransactionManagement
public class MultiDataSourceConfig {
    
    @Bean
    @Primary
    public DataSource primaryDataSource() {
        // 主數(shù)據(jù)源配置
    }
    
    @Bean
    public DataSource secondaryDataSource() {
        // 次要數(shù)據(jù)源配置
    }
    
    // 只配置了一個(gè)事務(wù)管理器
    @Bean
    public PlatformTransactionManager transactionManager() {
        return new DataSourceTransactionManager(primaryDataSource());
    }
}

@Configuration
@EnableTransactionManagement
public class MultiDataSourceConfig {
    
    @Bean
    @Primary
    public DataSource primaryDataSource() {
        // 主數(shù)據(jù)源配置
    }
    
    @Bean
    public DataSource secondaryDataSource() {
        // 次要數(shù)據(jù)源配置
    }
    
    @Bean
    @Primary
    public PlatformTransactionManager primaryTransactionManager() {
        return new DataSourceTransactionManager(primaryDataSource());
    }
    
    @Bean
    public PlatformTransactionManager secondaryTransactionManager() {
        return new DataSourceTransactionManager(secondaryDataSource());
    }
}

// 使用指定的事務(wù)管理器
@Service
public class UserService {
    
    @Transactional(transactionManager = "primaryTransactionManager")
    public void primaryDatabaseOperation(User user) {
        // 使用主數(shù)據(jù)源的事務(wù)
    }
    
    @Transactional(transactionManager = "secondaryTransactionManager")  
    public void secondaryDatabaseOperation(Log log) {
        // 使用次要數(shù)據(jù)源的事務(wù)
    }
}

@Transactional
public void debugTransaction() {
    TransactionStatus status = TransactionAspectSupport.currentTransactionStatus();
    System.out.println("是否是新事務(wù): " + status.isNewTransaction());
    System.out.println("是否有保存點(diǎn): " + status.hasSavepoint());
    System.out.println("是否已完成: " + status.isCompleted());
}

# application.properties
logging.level.org.springframework.transaction.interceptor=TRACE
logging.level.org.springframework.jdbc.datasource.DataSourceTransactionManager=DEBUG