Is it good practice to have Generic Exception class handler in global exception handler with spring rest?

Dhruv Kapatel :

I was referring few articles to create global exception handler using @ControllerAdvice for my rest api project using spring. The purpose of this is to send proper formatted response to the client in the case of exception occurred. In some articles they have added Throwable or Exception in global exception handler. Should I replace it with RunTimeException as this block is for exception occurred at runtime?

Exception Handler code:

@ControllerAdvice
public class GlobalExceptionHandler{

    @ExceptionHandler(NoDataFoundException.class)
    @ResponseStatus(code=HttpStatus.NOT_FOUND)
    public ResponseEntity<ErrorResponse> handle(NoDataFoundException ex){
        ErrorResponse errorResponse = new ErrorResponse(ex.getMessage(), HttpStatus.NOT_FOUND.value());
        ResponseEntity<ErrorResponse> response = new ResponseEntity<ErrorResponse>(errorResponse, HttpStatus.NOT_FOUND);
        return response;
    }
    ..... more methods to handle custom exceptions

    @ExceptionHandler(Exception.class)
    @ResponseStatus(code=HttpStatus.INTERNAL_SERVER_ERROR)
    public ResponseEntity<ErrorResponse> handle(Exception ex){
        ErrorResponse errorResponse = new ErrorResponse("Something went wrong", HttpStatus.INTERNAL_SERVER_ERROR.value());
        ResponseEntity<ErrorResponse> response = new ResponseEntity<ErrorResponse>(errorResponse, HttpStatus.INTERNAL_SERVER_ERROR);
        return response;
    }
}

ErrorResponse code:

public class ErrorResponse {

    private String message;
    private int statusCode;

    public ErrorResponse(String message, int statusCode) {
        super();
        this.message = message;
        this.statusCode = statusCode;
    }
    public String getMessage() {
        return message;
    }
    public void setMessage(String message) {
        this.message = message;
    }
    public int getStatusCode() {
        return statusCode;
    }
    public void setStatusCode(int statusCode) {
        this.statusCode = statusCode;
    }
}

References:

davidxxx :

Should I replace it with RunTimeException as this block is for exception occurred at runtime?

To make sure that you catch any exception thrown and never handled by your components or any exception handler with a more typed exception than Exception, you should have a handler for Exception.
A handler for RuntimeException is not enough because checked exception are also thrown at runtime and if the method declarations of your high level components specify throws Exception or throws "any checked exception", a checked exception could be propagated until the client or here the container that will apply a default behavior.
For example imagine this rest controller method declaration that could be make this situation to happen :

@RequestMapping(value = "/{id}", method = RequestMethod.GET)
public ResponseEntity<Foo> getOne(@PathVariable long id) throws Exception {
       // ....           
}

And to override this default Spring behavior, you will want to add a handler for Exception.
Of course it doesn't mean that declaring a handler only for Exception is the way but you may have some exception with no specific handling and for that a generic handling is fine.

Is it good practice to have Generic Exception class handler in global exception handler with spring rest?

Guess you like