No validator could be found for constraint 'jakarta.validation.constraints.Pattern' - error still appearing even after deleting validator from class

Question

I have used @Pattern to validate text input for a long time in my project and never had an issue. All of a sudden I'm getting the following error:

jakarta.validation.UnexpectedTypeException: HV000030: No validator could be found for constraint 'jakarta.validation.constraints.Pattern' validating type 'com.helpmesaythis.hmst3.profile.promo.model.entity.DiscountPromoCode'. Check configuration for 'discountPromoCode'

There are two strange things at play:

There are other classes using it without an issue and I haven't even touched this problematic class in a long time (it has always worked).

I have tried commenting out and even deleting it entirely from the class, yet the error still appears. How is it causing an issue when it doesn't even exist?

import com.helpmesaythis.hmst3.profile.partner.model.entity.Partner; 
import jakarta.persistence.*; 
import jakarta.validation.constraints.Pattern; 

@Entity 
@Table(name = "discount_promo_code") 
public class DiscountPromoCode { 
    ... 
    @Size(min = 4, max = 20, message = "Promo Code must be between 4-20 characters") 
    @Pattern(regexp = "[A-Za-z0-9]+$", message = "Promo Code can contain only letters and numbers") 
    @Column(name = "promo_code") 
    private String promoCode; 
    ... 
}

I have made sure that all dependencies are up to date. My Spring Boot is up to date.

Again - the @Pattern annotation works everywhere else, yet I get the same error message even after it has been deleted from the problematic class.

When I include spring.jpa.properties.javax.persistence.validation.mode=none everything works as it should.

Any ideas?

Answer 1

As andrewJames pointed out in the comments, the error was coming from the field discountPromoCode and not the class DiscountPromoCode. The error itself was because I was using @Pattern to validate a field that was not a String.