Java Portal | Программирование: “Spring Boot: ты можешь валидировать входные DTO через @Valid плюс анно…”

Spring Boot: ты можешь валидировать входные DTO через @Valid плюс аннотации вроде @NotBlank, @Email и т.д.

public class RegistrationRequest {

    @Email(message = "Please provide a valid email address")
    @NotBlank(message = "Email is required")
    private String email;

    @Size(min = 8, max = 16, message = "Password must be 8–16 characters long")
    private String password;

    @Pattern(
        regexp = "^[0-9]{10,15}$",
        message = "Phone number must be 10–15 digits"
    )
    private String phone;

    // getters & setters
}

By Default, if the validation fails Spring automatically returns a 400 Bad Request with a detailed error body like:

{
  "timestamp": "2025-01-01T12:00:00Z",
  "status": 400,
  "errors": [
    "Email is required",
    "Age must be at least 18"
  ]
}

You can customize the response by implementing a global exception handler

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