GlobalExceptionHandler.java

package org.petify.image.exception;

import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.HttpStatusCode;
import org.springframework.http.ProblemDetail;
import org.springframework.http.ResponseEntity;
import org.springframework.security.access.AccessDeniedException;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;
import org.springframework.web.context.request.WebRequest;
import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;

import java.time.Instant;
import java.util.HashMap;
import java.util.Map;

@RestControllerAdvice
public class GlobalExceptionHandler extends ResponseEntityExceptionHandler {

    @ExceptionHandler(AccessDeniedException.class)
    ProblemDetail handleAccessDeniedException(WebRequest request) {
        ProblemDetail problemDetail = ProblemDetail.forStatus(HttpStatus.FORBIDDEN);
        problemDetail.setTitle("Access Denied");
        problemDetail.setDetail(request.getDescription(false));
        problemDetail.setProperty("timestamp", Instant.now());
        return problemDetail;
    }

    @ExceptionHandler(Exception.class)
    ProblemDetail handleGenericException(Exception ex) {
        ProblemDetail problemDetail = ProblemDetail.forStatus(HttpStatus.INTERNAL_SERVER_ERROR);
        problemDetail.setTitle("Internal Server Error");
        problemDetail.setDetail("An unexpected error occurred: " + ex.getMessage());
        problemDetail.setProperty("timestamp", Instant.now());
        return problemDetail;
    }

    @Override
    protected ResponseEntity<Object> handleMethodArgumentNotValid(
            MethodArgumentNotValidException ex,
            HttpHeaders headers,
            HttpStatusCode status,
            WebRequest request) {

        ProblemDetail problemDetail = ProblemDetail.forStatus(status);
        problemDetail.setTitle("Validation Failed");

        Map<String, String> errors = new HashMap<>();
        ex.getBindingResult().getFieldErrors().forEach(error ->
                errors.put(error.getField(), error.getDefaultMessage())
        );

        problemDetail.setProperty("errors", errors);

        return new ResponseEntity<>(problemDetail, headers, status);
    }

    @ExceptionHandler(ImageNotFoundException.class)
    ProblemDetail handleImageNotFound(ImageNotFoundException ex) {
        ProblemDetail problemDetail = ProblemDetail.forStatus(HttpStatus.NOT_FOUND);
        problemDetail.setTitle("Image Not Found");
        problemDetail.setDetail(ex.getMessage());
        problemDetail.setProperty("timestamp", Instant.now());
        return problemDetail;
    }

    @ExceptionHandler(MaxImagesReachedException.class)
    ProblemDetail handleMaxImagesReached(MaxImagesReachedException ex) {
        ProblemDetail problemDetail = ProblemDetail.forStatus(HttpStatus.CONFLICT);
        problemDetail.setTitle("Max Images Reached");
        problemDetail.setDetail(ex.getMessage());
        problemDetail.setProperty("timestamp", Instant.now());
        return problemDetail;
    }
}