Bean validation for Integer field

Question

I am trying to have constraint validation on the field, which must reject if the input is not an integer.

public class ClientTO {
       private Integer phone_num; //
}

I tried:

1) @Digits - It does not validate if input is integer or not as you could see the type mismatch exception is still thrown.

2) My custom validation - which seems to not work on Integer fields

Error:

Exception in thread "main" javax.validation.UnexpectedTypeException: HV000030: No validator could be found for type: java.lang.Integer.

My custom validation class:

public class X_CVAImpl implements ConstraintValidator<X_CustomValidatorAnnotation,String>{  
    public boolean isValid(String value, ConstraintValidatorContext context) {
        // TODO Auto-generated method stub
        boolean val_d;
        if (value.matches("[0-9]+") && value.length() ==10) {
            val_d=true;
        }else {
            val_d=false;            
        }
        return val_d;
    }
}

Any help please?

Answer 1

@Digits will only work for primitive types. So if you change your entity to the following, your validation should kick in.

public class ClientTO {
   @Digits(integer=10, fraction=0)
   private int phone_num; // Constraint: phone_num can only be 10 digits long or less
   ...
}

Having that said, I believe that you should use a string to validate a phone number.

public class ClientTO {
   @Size(min=10, max=10)
   @Pattern(regexp="(^[0-9]{10})")
   private String phone_num; // Constraint: phone_num would match 10 digits number
   ...
}