Java防止重复提交订单的实现示例

@RestController
@RequestMapping("/api/order")
public class OrderTokenController {

    @Autowired
    private RedisTemplate<String, String> redisTemplate;

    @GetMapping("/token")
    public ResponseEntity<String> getToken() {
        String token = UUID.randomUUID().toString();
        String key = "order:token:" + token;

        // 设置有效期5分钟
        redisTemplate.opsForValue().set(key, "valid", Duration.ofMinutes(5));

        return ResponseEntity.ok(token);
    }
}

@RestController
@RequestMapping("/api/order")
public class OrderController {

    @Autowired
    private OrderService orderService;

    @PostMapping("/submit")
    public ResponseEntity<String> submitOrder(@RequestBody OrderRequest request,
                                              @RequestHeader("X-Order-Token") String token) {
        boolean success = orderService.submitOrder(request, token);
        if (success) {
            return ResponseEntity.ok("订单提交成功");
        } else {
            return ResponseEntity.status(HttpStatus.BAD_REQUEST).body("请勿重复提交订单");
        }
    }
}

@Service
public class OrderService {

    @Autowired
    private RedisTemplate<String, String> redisTemplate;

    /**
     * 提交订单接口，防止重复提交
     */
    public boolean submitOrder(OrderRequest request, String token) {
        String redisKey = "order:token:" + token;

        // 利用 Redis 的 delete + check 保证幂等性（原子性）
        Boolean result = redisTemplate.delete(redisKey);

        if (Boolean.TRUE.equals(result)) {
            // token存在并删除 → 第一次提交
            // 执行正常订单创建逻辑
            createOrder(request);
            return true;
        } else {
            // token 不存在 → 重复提交
            return false;
        }
    }

    private void createOrder(OrderRequest request) {
        // 实际业务处理：生成订单号、校验库存、扣减库存、写库、发MQ等
        System.out.println("处理订单：" + request);
    }
}

@Data
public class OrderRequest {
    private Long userId;
    private List<Long> productIds;
    private BigDecimal totalAmount;
}

// Lua 脚本实现原子删除
String script = "if redis.call('get', KEYS[1]) == ARGV[1] then " +
                "return redis.call('del', KEYS[1]) else return 0 end";

DefaultRedisScript<Long> redisScript = new DefaultRedisScript<>();
redisScript.setScriptText(script);
redisScript.setResultType(Long.class);

Long result = redisTemplate.execute(redisScript, Collections.singletonList(key), "valid");