如何在Spring boot中将用户id插入到产品中？

@Entity
public class Product {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    
    private Long userId;

    // 其他属性和方法省略...
}

@Service
public class ProductService {
    @Autowired
    private ProductRepository productRepository;

    public Product createProduct(Product product) {
        Long userId = getCurrentUserId();
        product.setUserId(userId);
        return productRepository.save(product);
    }

    private Long getCurrentUserId() {
        Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
        // 根据具体的认证授权机制获取当前用户的ID
        // 例如，如果使用Spring Security，可以通过以下方式获取：
        // UserDetails userDetails = (UserDetails) authentication.getPrincipal();
        // return userDetails.getId();
        return null; // 替换为获取当前用户ID的实际逻辑
    }
}

@RestController
public class ProductController {
    @Autowired
    private ProductService productService;

    @PostMapping("/products")
    public Product createProduct(@RequestBody Product product) {
        return productService.createProduct(product);
    }

    // 其他接口方法省略...
}