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Java Spring - Handle exception thrown when #RequestBody is null

I have a rest api in Java Spring Boot. I am making a POST request to api. If there is a data in the body it works fine but when no data is passed, it gives a 400 Bad Request response:
{
"timestamp": "2021-05-03T13:32:36.746+0000",
"status": 400,
"error": "Bad Request",
"message": "Required request body is missing: public org.springframework.http.ResponseEntity<com.package.MyResponse> com.package.MyController.getData(com.package.MyRequest)",
"path": "/api/"
}
How can I hide the package information and class name from the message in response? It should return mesage as:
"message": "Required request body is missing."
One option is to set #RequestBody(required=false) and then handle manually inside, but I want to avoid.
It would be great if someone can help. Thank you.

You can create a RestControllerAdvice extend it with ResponseEntityExceptionHandler. In implementation override corresponding method and send your custom message. In your case method will be handleHttpMessageNotReadable from ResponseEntityExceptionHandler.
Here is the sample code:
/**
* Intercept exception to response with error
*/
#RestControllerAdvice
public class ApplicationExceptionHandler extends ResponseEntityExceptionHandler {
/**
* {#inheritDoc}
*/
#Override
protected ResponseEntity<Object> handleHttpMessageNotReadable(HttpMessageNotReadableException ex, HttpHeaders headers,
HttpStatus status, WebRequest request) {
// your custom implementation
}
}

How to change Status code in spring boot error response?

I am making a simple rest service that makes some http calls and aggregates data using RestTemplate.
Sometimes i get NotFound error and sometimes BadRequest errors.
I want to respond with the same status code to my client and Spring seems to have this mapping out of the box. the message is okay but the Status code is always 500 Internal Server error.
I Would like to map my status code to the one i am initially receiving
"timestamp": "2019-07-01T17:56:04.539+0000",
"status": 500,
"error": "Internal Server Error",
"message": "400 Bad Request",
"path": "/8b8a38a9-a290-4560-84f6-3d4466e8d7901"
}
i would like it to be this way
"timestamp": "2019-07-01T17:56:04.539+0000",
"status": 400,
"error": "Internal Server Error",
"message": "400 Bad Request",
"path": "/8b8a38a9-a290-4560-84f6-3d4466e8d7901"
}
It throws HttpClientErrorException.BadRequest or HttpClientErrorException.NotFound
my code is a simple endpoint :
#GetMapping("/{id}")
public MyModel getInfo(#PathVariable String id){
return MyService.getInfo(id);
}

You can create global exception handling with #ControllerAdvice annotation. Like this:
#ControllerAdvice
public class RestResponseEntityExceptionHandler extends ResponseEntityExceptionHandler {
#ExceptionHandler(value = YourExceptionTypes.class)
protected ResponseEntity<Object> handleBusinessException(RuntimeException exception, WebRequest request) {
return handleExceptionInternal(exception, exception.getMessage(), new HttpHeaders(), HttpStatus.NOT_ACCEPTABLE, request);
}
}
When an exception is thrown, the handler will catch and transform it to the desired response. The original exception wont be propagated.

The accepted solution with the #ControllerAdvice is insufficient. That surely marks the response with the custom status code for the exception. It does, however, not return the wanted response body as JSON but as only simple string - the message from the exception.
To get the correct status code and the default error body the DefaultErrorAttributes can help.
#ControllerAdvice
public class PackedTemplateNotRecodableExceptionControllerAdvice extends ResponseEntityExceptionHandler {
#Autowired
private DefaultErrorAttributes defaultErrorAttributes;
#ExceptionHandler(PackedTemplateNotRecodableException.class)
public ResponseEntity<Object> handlePackedTemplateNotRecodableException(final RuntimeException exception, final WebRequest webRequest) {
// build the default error response
webRequest.setAttribute(RequestDispatcher.ERROR_STATUS_CODE, HttpStatus.BAD_REQUEST.value(), RequestAttributes.SCOPE_REQUEST);
final Map<String, Object> errorAttributes = defaultErrorAttributes.getErrorAttributes(webRequest, ErrorAttributeOptions.defaults());
// return the error response with the specific response code
return handleExceptionInternal(exception, errorAttributes, new HttpHeaders(), HttpStatus.BAD_REQUEST, webRequest);
}
}
That way you'll receive the wanted error response, e.g. something like this:
{
"timestamp": "2019-07-01T17:56:04.539+0000",
"status": 400,
"error": "Internal Server Error",
"message": "400 Bad Request",
"path": "/8b8a38a9-a290-4560-84f6-3d4466e8d7901"
}

I have spent a lot of time looking into this issue, including solutions from answers here, which didn't work for me (or I didn't implement correctly).
I finally got a breakthrough. Instead of throwing a generic Exception such as throw new Exception(message), I created classes that extends the Exception class for the specific exception type - with their respective HTTP error codes and message
#ResponseStatus(value = HttpStatus.BAD_REQUEST)
public class BadRequestException extends Exception{
public BadRequestException(String message) {
super(message);
}
}
In your application logic, you can now throw the Bad Request exception with a message like so throw new BadRequestException("Invalid Email"). This will result in an exception thrown thus :
{
"timestamp": "2021-03-01T17:56:04.539+0000",
"status": 400,
"error": "Bad Request",
"message": "Invalid Email",
"path": "path to controller"
}
You can now create other custom exception classes for the different exceptions you want, following the above example and changing the value parameter in the #ResponseStatus, to match the desired response code you want. e.g for a NOT FOUND exception #ResponseStatus (value = HttpStatus.NOT_FOUND), Java provides the different HTTP status codes via the HttpStatus enum.
For more context
I hope this is detailed enough and helps someone :)

Possible duplicate of Spring Resttemplate exception handling Your code needs a controller advice to handle the exceptions from the service it is calling.

HttpMediaTypeNotAcceptableException for errors with text/plain message response?

I have a simple webservice that returns content either as json or as plain text (depending on the clients' accept http header).
Problem: if an error occurs during text/plain request, Spring somehow returns a 406 Not Acceptable. Which is kind of wrong, because spring could as well just write the error out as plain error text, and moreover should absolutely preserve the 400 error status:
#RestController
public class TestServlet {
#PostMapping(value = "/test", produces = {APPLICATION_JSON_VALUE, TEXT_PLAIN_VALUE, "text/csv"})
public Object post() {
throw new BadRequestException("bad req");
}
}
#ResponseStatus(HttpStatus.BAD_REQUEST)
public class BadRequestException extends RuntimeException {
public BadRequestException(String msg) {
super(msg);
}
}
POST request with accept=application/json:
{
"timestamp": "2018-07-30T14:26:02",
"status": 400,
"error": "Bad Request",
"message": "bad req",
"path": "/test"
}
BUT with accept=text/csv (or text/plain) shows an empty response with status 406 Not Acceptable.
I also noticed the DispatcherServlet.processDispatchResult() is called twice: first with my BadRequest exception, 2nd time with HttpMediaTypeNotAcceptableException. So clearly the rendering of my custom exception fails, but why?

The problem is the restrictive Accept header allowing only one content type as response. In case of an error, Spring MVC needs to handle the BadRequestException and produce the required content type using a registered HttpMessageConverter.
By default Spring Boot has no message converter to produce text/plain directly from any object. You may register an ObjectToStringHttpMessageConverter (as a bean should work for Spring Boot) to allow this and you will get the result of BadRequestException.toString() as response body.
I assume a similar problem for text/csv but I am not sure how your setup for CSV message conversion looks like.

The condition written in "produces" determines the media type to use for the response to be "text/csv". So For a success scenario it works fine, **
but when you go for rendering an exception with a JSON body that
becomes a problem and gives you a 406 instead.
**

in latest versions of spring framework the problem fixes, but in old versions,as mentioned in Spring JIRA comments you should remove HandlerMapping.PRODUCIBLE_MEDIA_TYPES_ATTRIBUTE attribute from request
the code might be like this :
#RestControllerAdvice
public class ExampleControllerAdvice {
#ExceptionHandler(value = Exception.class)
public ResponseEntity<?> handleException(HttpServletRequest request, Exception e) {
request.removeAttribute(
HandlerMapping.PRODUCIBLE_MEDIA_TYPES_ATTRIBUTE);
return new ResponseEntity<?>(response, HttpStatus.INTERNAL_SERVER_ERROR);
}
}

we can handle exception in advice
#ControllerAdvice
class ExceptionHandler{
#ExceptionHandler(value = {HttpMediaTypeNotAcceptableException.class})
public ResponseEntity handleMediaTypeException(HttpMediaTypeNotAcceptableException e) {
APIErrorResponse apiErrorResponse = new APIErrorResponse();
apiErrorResponse.setErrorCode("set custom code here");
apiErrorResponse.setErrorMessage("set custom meggage here/ here we can use message from object of exception i.e e.getMessage()");
return new ResponseEntity<>(errorDetails, HttpStatus.BAD_REQUEST);
}
}

consume Rest api with two different responses

I am trying to consume api with two different responses. when providing proper input and headers, it gives one json object. That is working fine with code given below.
but when one of the inputs or headers are missing then api is returning other json which states error details while hitting through Postman but same is not getting achieved by client code. It throws exception but api should return json with error details.
first I tried with postForobject(), then changed to exchange() assuming postForObject returning object and api is not getting expected object format. so tried with String.clas instead of particular class
what can be done to get two different json object by hitting same url?
when success:
{
"contacts": [
{
"input": "98########",
"status": "valid"
}
]
}
when input or header missing:
"errors": [
{
"code": 1###,
"title": "Access denied",
"details": "invalid deatils"
}
]
below is my code:
public static void main(String[] args) throws Exception {
RestTemplate restTemplate = new RestTemplate();
String check_Contact_Async = "https://port/contacts/";
sslByPass();
//headers = setHeaders();
contactsDTO = getInput();
final HttpEntity<ContactsDTO> entity = new HttpEntity<ContactsDTO>(contactsDTO, headers);
try {
//WsResponse res = restTemplate.postForObject(check_Contact_Async, entity, WsResponse.class);
ResponseEntity<String> responseEntity = restTemplate.exchange(
check_Contact_Async, HttpMethod.POST, entity,
String.class);
System.out.println(responseEntity);
} catch (Exception exception) {
System.out.println(exception);
}
}
Exception in thread "main" org.springframework.web.client.HttpClientErrorException: 401 Unauthorized
at org.springframework.web.client.DefaultResponseErrorHandler.handleError(DefaultResponseErrorHandler.java:91)
at org.springframework.web.client.RestTemplate.handleResponse(RestTemplate.java:667)
at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:620)
at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:580)
at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:498)
at com.websystique.springmvc.apitest.Example.main(Example.java:120)
any clue will be helpful
Thanks

Exception handler doesn't use the value in #ResponseStatus

I have the following controller advice to handle the exceptions within my app globally:
#ControllerAdvice
public class ExceptionHandlingController {
// Convert a predefined exception to an HTTP Status code
#ResponseStatus(value=HttpStatus.BAD_REQUEST) // 400
#ExceptionHandler(ConstraintViolationException.class)
public void ConstraintViolationExceptionHandler() {
//Nothing to do
}
}
The code below is the controller, which tries to save an object to the db (in the service layer). The class that object belongs to, has annotations that fail.
#RequestMapping(value = "/signup", method = RequestMethod.POST)
public void create(#RequestBody CustomUserDetails user, HttpServletResponse response) {
logger.debug("User signup attempt with username: " + username);
userDetailsServices.saveIfNotExists(user);
}
I expect the client to receive a 400 response when ConstraintViolationException is thrown.
When the method returns void , no response is returned. When I change it String and return a random text, I get 404 response back.
{
"timestamp": 1495489172770,
"status": 404,
"error": "Not Found",
"exception": "javax.validation.ConstraintViolationException",
"message": "Validation failed for classes [security.model.CustomUserDetails] during persist time for groups [javax.validation.groups.Default, ]\nList of constraint violations:[\n\tConstraintViolationImpl{interpolatedMessage='must match \"^(?!.*\\..*\\..*)[A-Za-z]([A-Za-z0-9.]*[A-Za-z0-9]){8,15}$\"', propertyPath=username, rootBeanClass=class com.boot.cut_costs.security.model.CustomUserDetails, messageTemplate='{javax.validation.constraints.Pattern.message}'}\n]",
"path": "/signup"
}
How can I make this return a simple BAD REQUEST message as it is defined for the #ExceptionHandler.
Note: ConstraintViolationExceptionHandler is hit!