spring_boot_exception_handler.java

import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.transaction.TransactionSystemException;
import org.springframework.validation.FieldError;
import org.springframework.validation.ObjectError;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.MissingServletRequestParameterException;
import org.springframework.web.bind.annotation.ControllerAdvice;
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.method.annotation.MethodArgumentTypeMismatchException;
import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;

import javax.persistence.RollbackException;
import javax.validation.ConstraintViolation;
import javax.validation.ConstraintViolationException;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.stream.Collectors;

//@Order(Ordered.HIGHEST_PRECEDENCE)
//@RestControllerAdvice
@ControllerAdvice
public class RestExceptionHandler extends ResponseEntityExceptionHandler {



    @Override
    protected ResponseEntity<Object> handleMethodArgumentNotValid(
            MethodArgumentNotValidException ex,
            HttpHeaders headers,
            HttpStatus status,
            WebRequest request) {
        List<String> errors = new ArrayList<String>();
        for (FieldError error : ex.getBindingResult().getFieldErrors()) {
            errors.add(error.getField() + ": " + error.getDefaultMessage());
        }
        for (ObjectError error : ex.getBindingResult().getGlobalErrors()) {
            errors.add(error.getObjectName() + ": " + error.getDefaultMessage());
        }

        ApiError apiError =
                new ApiError(HttpStatus.BAD_REQUEST, ex.getLocalizedMessage(), errors);
        return handleExceptionInternal(
                ex, apiError, headers, apiError.getStatus(), request);
    }


    @Override
    protected ResponseEntity<Object> handleMissingServletRequestParameter(
            MissingServletRequestParameterException ex, HttpHeaders headers,
            HttpStatus status, WebRequest request) {
        String error = ex.getParameterName() + " parameter is missing";

        ApiError apiError =
                new ApiError(HttpStatus.BAD_REQUEST, ex.getLocalizedMessage(), error);
        return new ResponseEntity<Object>(
                apiError, new HttpHeaders(), apiError.getStatus());
    }


    @ExceptionHandler({ ConstraintViolationException.class })
    public ResponseEntity<Object> handleConstraintViolation(
            ConstraintViolationException ex, WebRequest request) {
        List<String> errors = new ArrayList<String>();
        for (ConstraintViolation<?> violation : ex.getConstraintViolations()) {
            errors.add(violation.getRootBeanClass().getName() + " " +
                    violation.getPropertyPath() + ": " + violation.getMessage());
        }

        ApiError apiError =
                new ApiError(HttpStatus.BAD_REQUEST, ex.getLocalizedMessage(), errors);
        return new ResponseEntity<Object>(
                apiError, new HttpHeaders(), apiError.getStatus());
    }


    @ExceptionHandler({ MethodArgumentTypeMismatchException.class })
    public ResponseEntity<Object> handleMethodArgumentTypeMismatch(
            MethodArgumentTypeMismatchException ex, WebRequest request) {
        String error =
                ex.getName() + " should be of type " + ex.getRequiredType().getName();

        ApiError apiError =
                new ApiError(HttpStatus.BAD_REQUEST, ex.getLocalizedMessage(), error);
        return new ResponseEntity<Object>(
                apiError, new HttpHeaders(), apiError.getStatus());
    }



}