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kotlinlang

Can anyone help explain why my validation isn't working?

```data class Credential(
        @field:JsonProperty("country_code")
        @field:Pattern(regexp = "^[A-Z]{2}$", message = "country_code must be a string of 2 capital letters i.e. DE")
        val countryCode: String? = null,
)```
With
```fun registerCredentials(@Validated @RequestBody credential: Credential):Credential{ 
   //...
}```
I've tried `@Valid` and that doesn't work either. I don't get any error, I just ged a object with null values.

Is `hibernate validator` in the classpath?
<https://mvnrepository.com/artifact/org.hibernate/hibernate-validator|https://mvnrepository.com/artifact/org.hibernate/hibernate-validator>

Thanks for the response. I added that and it didn't work. I then added  `spring-boot-starter-validation` and I now  get validation errors :smile: