无法序列化（Spring Boot）

Question

我正在开发一个简单的应用程序来学习 Redis 缓存。在我将 Redis 添加为 Spring Boot 项目上的缓存机制之前，API 工作正常。你可以说REST项目。使用Postman来调用不同的API。添加redis后，我发现用于删除数据的

@CacheEvict

工作正常。但是当我调用像GetMapping，PutMapping这样用

@Cacheable

注释的请求时，

@CachePut

不起作用。我不明白

@CacheEvict

完美工作

@Cacheable

，

@CachePut

不工作有什么问题。

这是当我使用以下网址调用 API 时邮递员给出的 错误：
放置：

http://localhost:8080/bank/2/deposit

获取：

http://localhost:8080/bank/holderName/Aysha

{
    "dateTime": "2024-03-30T16:49:17.7557062",
    "message": "Cannot serialize",
    "error": "uri=/bank/2/deposit",
    "path": "Bad Request"
}

让我更详细地解释一下我是如何配置redis的：

POM：

<!-- https://mvnrepository.com/artifact/redis.clients/jedis -->
<dependency>
    <groupId>redis.clients</groupId>
    <artifactId>jedis</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-cache</artifactId>
</dependency>

应用程序属性：

spring.cache.type=redis
spring.cache.redis.time-to-live=60000
spring.cache.redis.host=localhost
spring.cache.redis.port=6379

账户（实体）：

@Entity
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Account implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String holderName;
    private double balance;
}

这里我启用了缓存：

@SpringBootApplication
@EnableCaching
public class SimpleBankingApplication {

    @Bean
    public ModelMapper mapper(){
        return new ModelMapper();
    }

    public static void main(String[] args) {
        SpringApplication.run(SimpleBankingApplication.class, args);
    }

}

控制器类：

@Controller
@RequestMapping("bank")
@AllArgsConstructor
@CacheConfig(cacheNames = "account")
public class AccountController {
    private AccountService service;

    @PostMapping("createAccount")
    public ResponseEntity<AccountDTO> createAccount(@RequestBody @Valid AccountDTO dto){
        return new ResponseEntity<>(service.addAccount(dto), HttpStatus.CREATED);
    }
    @GetMapping("holderName/{name}")
    @Cacheable(value = "account", key = "#name")
    public ResponseEntity<AccountDTO> getAccountByName(@PathVariable String name){
        return new ResponseEntity<>(service.getAccount(name),HttpStatus.ACCEPTED);
    }
    @PutMapping("{id}/deposit")
    @CachePut(cacheNames = "account", key = "#id")
    public ResponseEntity<AccountDTO> deposit(@PathVariable Long id, @RequestBody Map<String, Double> request){
        Double value = request.get("balance");
        return new ResponseEntity<>(service.deposit(id,value), HttpStatus.ACCEPTED);
    }
    @PutMapping("{id}/withdraw")
    public ResponseEntity<AccountDTO> withdraw(@PathVariable Long id, @RequestBody Map<String, Double> request){
        Double value = request.get("withdraw_balance");
        return new ResponseEntity<>(service.withdraw(id,value), HttpStatus.ACCEPTED);
    }
    @GetMapping("allAccounts")
    public ResponseEntity<List<AccountDTO>> getAllAccount(){
        return new ResponseEntity<>(service.getAllAccounts(),HttpStatus.ACCEPTED);
    }
    @DeleteMapping("deleteAccount/{id}")
    @CacheEvict(cacheNames = "account", key = "#id", beforeInvocation = true)
    public ResponseEntity<String> deleteAccount(@PathVariable Long id){
        service.delete(id);
        return new ResponseEntity<>("Account has been deleted!!!", HttpStatus.ACCEPTED);
    }
}

项目链接： 查看项目

Answer 1

问题是控制器类上的注释错误：

@Controller

应该是：

@RestController

后者专用于 REST API 控制器，与 Web 控制器相反。不同之处在于添加了

@ResponseBody

注释。它负责将响应对象正确序列化为 JSON。这部分在您的情况下抛出异常。