如何将 getLocalizedMessage() 转换为自定义异常对象 - MismatchedInputException答案

【问题标题】：How to conver getLocalizedMessage() to Custom Exception Object - MismatchedInputException如何将 getLocalizedMessage() 转换为自定义异常对象 - MismatchedInputException
【发布时间】：2022-08-02 18:59:53
【问题描述】：

当我发送 restTemplate.postForEntity 我想捕捉异常

public DriverDTO create(CreateDriverForm createDriverForm) throws JsonProcessingException {
    try {
        ...
        ResponseEntity<DriverDTO> responseEntity =
                restTemplate.postForEntity(\"http://localhost:8081/drivers\", entity, DriverDTO.class);
        return responseEntity.getBody();
    } catch (HttpClientErrorException exception) {
        ExceptionResponseObject object = objectMapper.readValue(exception.getLocalizedMessage(), ExceptionResponseObject.class);
       
    }
}

并将 exception.getLocalizedMessage() 从 Rest Api 转换为我的自定义异常响应对象：

@Data
@AllArgsConstructor
@NoArgsConstructor
public class ExceptionResponseObject {
    private LocalDateTime timestamp;
    private int status;
    private String errorName;
    private String message;
}

但我收到以下错误：

com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot construct instance of 
`com.example.ekrany.responses.ExceptionResponseObject` (although at least one Creator exists): 
no int/Int-argument constructor/factory method to deserialize from Number value (400)
 at [Source: (String)\"400 : \"{\"timestamp\":\"2022-08-02T12:00:13.3734961\",\"status\":400,
\"errorName\":\"MethodArgumentNotValidException\",\"message\":\"[Email already exists]\"}\"\"; line: 1, column: 1]

我应该如何转换它？或者，当我发布任何表单并出现错误时，是否有更好的做法来处理来自 api 的 4xx 状态？

标签： spring exception servlets objectmapper

【解决方案1】：

因为如果它的错误它不能转换为驱动程序TO。试试这样

    ResponseEntity<String> responseEntity =
                restTemplate.postForEntity("http://localhost:8081/drivers", entity, String.class);
if (responseEntity.statusCode == 200){
objectMapper.readValue(responseEntity.getBody(), DriverDTO.class);
}
else{
ExceptionResponseObject object = objectMapper.readValue(exception.getLocalizedMessage(), ExceptionResponseObject.class);
}

【讨论】：