Natan Code

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-validation</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

import jakarta.validation.constraints.*;
import lombok.Getter;
import lombok.Setter;

import java.math.BigDecimal;

@Getter
@Setter
public class ProductInput {

    @PositiveOrZero
    private Long id;

    @NotBlank
    private String name;

    @NotBlank
    private String description;

    @PositiveOrZero
    private BigDecimal price;

    @NotNull
    private Boolean active;

}

import lombok.Getter;

@Getter
public enum ProblemType {

    INVALID_DATA("/invalid-data", "Invalid Data");

    private String title;
    private String uri;

    ProblemType(String path, String title) {
        this.uri = "http://localhost:8080" + path;
        this.title =  title;
    }

}

import com.fasterxml.jackson.annotation.JsonInclude;
import lombok.Builder;
import lombok.Getter;

import java.time.OffsetDateTime;
import java.util.List;

@JsonInclude(JsonInclude.Include.NON_NULL)
@Getter
@Builder
public class Problem {

    private Integer status;
    private String type;
    private String title;
    private String detail;
    private String userMessage;
    private OffsetDateTime timestamp;
    private List<Object> errors;

    @Getter
    @Builder
    public static class Object {

        private String name;
        private String userMessage;

    }
}

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.MessageSource;
import org.springframework.context.i18n.LocaleContextHolder;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.HttpStatusCode;
import org.springframework.http.ResponseEntity;
import org.springframework.lang.Nullable;
import org.springframework.validation.BindingResult;
import org.springframework.validation.FieldError;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.context.request.WebRequest;
import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;

import java.time.OffsetDateTime;
import java.util.List;

@ControllerAdvice
public class ApiExceptionHandler extends ResponseEntityExceptionHandler {

    @Autowired
    private MessageSource messageSource;

    @Override
    @Nullable
    protected ResponseEntity<Object> handleMethodArgumentNotValid(MethodArgumentNotValidException ex, HttpHeaders headers, HttpStatusCode status, WebRequest request) {
        return handleValidationInternal(ex, headers, HttpStatus.resolve(status.value()), request, ex.getBindingResult());
    }

    private ResponseEntity<Object> handleValidationInternal(Exception ex, HttpHeaders headers,
                                                            HttpStatus status, WebRequest request, BindingResult bindingResult) {

        ProblemType problemType = ProblemType.INVALID_DATA;
        String detail = "One or more fields are invalid.";

        List<Problem.Object> errors = bindingResult.getAllErrors().stream()
                .map(objectError -> {
                    String message = messageSource.getMessage(objectError, LocaleContextHolder.getLocale());

                    String name = objectError.getObjectName();

                    if (objectError instanceof FieldError) {
                        name = ((FieldError) objectError).getField();
                    }

                    return Problem.Object.builder()
                            .name(name)
                            .userMessage(message)
                            .build();
                })
                .toList();

        Problem problem = createProblemBuilder(status, problemType, detail)
                .userMessage(detail)
                .errors(errors)
                .build();

        return handleExceptionInternal(ex, problem, headers, status, request);
    }

    private Problem.ProblemBuilder createProblemBuilder(HttpStatus status, ProblemType problemType, String detail) {

        return Problem.builder()
                .status(status.value())
                .type(problemType.getUri())
                .title(problemType.getTitle())
                .timestamp(OffsetDateTime.now())
                .detail(detail);
    }

}

import com.natancode.validation.api.v1.model.input.ProductInput;
import jakarta.validation.Valid;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;

@RestController
@RequestMapping(value = "/v1/products")
public class ProductController {

    @PostMapping
    @ResponseStatus(HttpStatus.CREATED)
    public ResponseEntity<?> insert(@RequestBody @Valid ProductInput productInput) {
        return ResponseEntity.ok(productInput);
    }

}

{
    "id": -1,
    "description": "keyboard 123",
    "price": 99.99,
    "active": true
}

{
    "status": 400,
    "type": "http://localhost:8080/invalid-data",
    "title": "Invalid Data",
    "detail": "One or more fields are invalid.",
    "userMessage": "One or more fields are invalid.",
    "timestamp": "2025-08-26T15:12:31.599317-03:00",
    "errors": [
        {
            "name": "id",
            "userMessage": "must be greater than or equal to 0"
        },
        {
            "name": "name",
            "userMessage": "must not be blank"
        }
    ]
}