如何使用 ResponseEntity 来 return 来自 REST 调用的简单错误消息？

Question

我有一个用 Java 和 Spring MVC 编写的网络应用程序。

有一个 REST Web 服务，当它工作时，我以 JSON 格式返回 Employee。

但是如果出现错误，我会返回一个很大的 JSON 字符串，其中包含 HTML 错误页面，但不包含我的 sErrorMsg 字符串（错误示例 JSON 包含在下面）。

问题：如何让错误响应成为一个简单的 JSON 字符串，其中包含我的错误消息？

@RequestMapping(value = "/json/employee/{employeeId}", method = RequestMethod.GET)
@ResponseBody
public ResponseEntity<Employee> getEmployee(@PathVariable("employeeId") int employeeId) throws Exception {

   Employee employee = null;
   String sErrorMsg = "";
   try {
     employee = employeeService.getEmployee(employeeId);
   } catch (Exception x) {
     sErrorMsg = "Error getting employee; "+x.getMessage();
     // UPDATE:
     // throw x; <<-- errant line here was causing the problem
     //
   }

   ResponseEntity responseEntity = null;
   if (ret != null) {
       ResponseEntity responseEntity = ResponseEntity.ok(employee);
   } else {
       responseEntity = ResponseEntity.badRequest().body(sErrorMsg);
   }

   return responseEntity;
}

错误JSON ...

{"readyState":4,"responseText":"<!doctype html><html lang=\"en\"><head><title>HTTP Status 500 – Internal Server Error</title><style type=\"text/css\">body {font-family:Tahoma,Arial,sans-serif;} h1, h2, h3, b {color:white;background-color:#525D76;} h1 {font-size:22px;} h2 {font-size:16px;} h3 {font-size:14px;} p {font-size:12px;} a {color:black;} .line /* the rest of the HTML which contains a length Java stack trace ... */ }

Answer 1

问题是我自己造成的 throw x 在这里...

   } catch (Exception x) {
     sErrorMsg = "Error getting employee; "+x.getMessage();
     throw x; // <<-- errant line here was causing the problem
   }

我删除了 throw x;，一切正常。

Answer 2

我做了这样的事情：

    @GetMapping("/get/findByTsId")
    public ResponseEntity<JsonPayLoad> findByTsId(String id) throws JsonProcessingException{

        try{
            JsonPayLoad payload =  this.splunkService.findByTsId(id);
            log.info("search request for TsId \t {} received at ->>> {}",id, LocalDateTime.now());
            log.info("match found \n {}",  payload.toString());

            return  ResponseEntity.ok(payload);

        } catch(NullPointerException nullPointerException){
            ObjectMapper mapper = new ObjectMapper();
            String message = "{\"result\": \"no match found for id: " + id+ "\"}";
            JsonPayLoad jsonPayLoad = new JsonPayLoad() ;

            JsonNode messageValue = mapper.readTree(message);
            jsonPayLoad.setPayload(messageValue);
            jsonPayLoad.setTimeStamp((LocalDateTime.now()).toString());


            log.info("search request for TsId \t {} received at ->>> {}",id, LocalDateTime.now());
            log.info("no match found \n {}",  jsonPayLoad);
            return ResponseEntity.status(HttpStatus.NOT_FOUND).body(jsonPayLoad);

        }

}

如何使用 ResponseEntity 来 return 来自 REST 调用的简单错误消息？

How do I use ResponseEntity to return simple error message from my REST call?

spring-mvc

spring-rest