java - 异常传播

Question

如何将对下游服务的调用中引发的异常传播给调用方方法？

我有一个服务可以计算一些内容并在出现错误时抛出异常:

{
  "timestamp": "2019-03-12T08:21:05.316+0000",
  "status": 500,
  "error": "Internal Server Error",
  "message": "VAKUUTUSVUOSI.MAKSUEHTO is null or not numeric. Can't be added to due date.",
  "path": "/rules/yk32/deducePaymentDueDate"
}

但调用服务显示此异常:

{
    "timestamp": "2019-03-12T08:30:22.912+0000",
    "status": 500,
    "error": "Internal Server Error",
    "message": "500 null",
    "path": "/calculation/annual/payment"
}

如何让调用者方法也显示服务抛出“/rules/yk32/deducePaymentDueDate”而不是“内部服务器错误”的消息？

调用方式:

LocalDate paymentDueDate = ykServiceAdapter.yk32DeducePaymentDueDate(requestDTO);

调用ykServiceadapter中的函数:

public LocalDate yk32DeducePaymentDueDate(Yk32RequestDTO requestDTO) {
    ResponseEntity<LocalDate> re;
    HttpEntity<?> entity = new HttpEntity<>(requestDTO);
    try {
        re = getRestTemplate().exchange(
                buildServiceUrl(externalServiceConfig, RULE_YK32, DEDUCE_PAYMENT_DUEDATE),
                HttpMethod.POST, entity,
                new ParameterizedTypeReference<LocalDate>() {
                });
        return re.getBody();

    } catch (HttpClientErrorException ex) {
        if (HttpStatus.NOT_FOUND.equals(ex.getStatusCode())) {
            return null;
        } else {
            throw ex;
        }
    }
}

Answer 1

您正在通过 HTTP 处理两个独立的上下文。

这意味着由 yk32DeducePaymentDueDate 生成的 Exception 被转换为 HTTP 500 响应，其中 < strong>可能表示Exception消息用作响应正文。

显然，由于原始的Exception在HTTP调用期间丢失，RestTemplate只能创建一个HttpClientErrorException 基于 HTTP 状态代码

HttpClientErrorException.BadRequest
HttpClientErrorException.Conflict
HttpClientErrorException.Forbidden
HttpClientErrorException.Gone
HttpClientErrorException.MethodNotAllowed
HttpClientErrorException.NotAcceptable
HttpClientErrorException.NotFound
HttpClientErrorException.TooManyRequests
HttpClientErrorException.Unauthorized
HttpServerErrorException.InternalServerError
HttpServerErrorException.NotImplemented
...

在您的情况下，实例化的Exception是

public static class InternalServerError extends HttpServerErrorException {
    InternalServerError(String statusText, HttpHeaders headers, byte[] body, @Nullable Charset charset) {
        super(HttpStatus.INTERNAL_SERVER_ERROR, statusText, headers, body, charset);
    }
}

<小时/>

只有 Exception 消息可能会被恢复(如果它已在响应正文中传输)。

您可能想要研究自定义的 ResponseErrorHandler，您可以在其中检查完整的 HTTP 响应并做出相应的 react 。