Question

I have written a JSR303 validator that compares property value to constraint:

@Documented
@Constraint(validatedBy = Cmp.LongCmpValidator.class)
@Target({ METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER })
@Retention(RUNTIME)
public @interface Cmp {
    String message() default "{home.lang.validator.Cmp.message}";
    Class<?>[] groups() default {};
    Class<? extends Payload>[] payload() default {};
    long value();
    public enum REL { LT,LT_EQ,EQ,GT,GT_EQ;
        @Override
        public String toString() {
            return toString_property();
        }
        public String toString_property() {
            switch(this) {
                case LT   : return "{home.lang.validator.Cmp.REL.LT}";
                case LT_EQ: return "{home.lang.validator.Cmp.REL.LT_EQ}";
                case    EQ: return "{home.lang.validator.Cmp.REL.EQ}";
                case GT   : return "{home.lang.validator.Cmp.REL.GT}";
                case GT_EQ: return "{home.lang.validator.Cmp.REL.GT_EQ}";
            }
            throw new UnsupportedOperationException();
        }
        public String toString_common() { return super.toString(); }
        public String toString_math() { switch(this) {
                case LT   : return "<";
                case LT_EQ: return "\u2264";
                case    EQ: return "=";
                case GT   : return ">";
                case GT_EQ: return "\u2265";
            }
            throw new UnsupportedOperationException();
        }
    }
    REL prop_rel_cnstr();

    @Target({ METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER })
    @Retention(RUNTIME)
    @Documented
    @interface List {
        Cmp[] value();
    }

    class LongCmpValidator implements ConstraintValidator<Cmp, Number> {
        long cnstr_val;
        REL prop_rel_cnstr;

        public void initialize(Cmp constraintAnnotation) {
            cnstr_val = constraintAnnotation.value();
            prop_rel_cnstr = constraintAnnotation.prop_rel_cnstr();
        }

        public boolean isValid(Number _value, ConstraintValidatorContext context) {
            if(_value == null) return true;

            if(_value instanceof Integer) {
                int value = _value.intValue();
                switch(prop_rel_cnstr) {
                    case LT   : return value <  cnstr_val;
                    case LT_EQ: return value <= cnstr_val;
                    case    EQ: return value == cnstr_val;
                    case GT   : return value >  cnstr_val;
                    case GT_EQ: return value >= cnstr_val;
                }
            }
            // ... handle other types
            return true;
        }
    }
}

ValidationMessages.properties :

home.lang.validator.Cmp.REL.LT=less than
home.lang.validator.Cmp.REL.LT_EQ=less than or equal
home.lang.validator.Cmp.REL.EQ=equal
home.lang.validator.Cmp.REL.GT=greater
home.lang.validator.Cmp.REL.GT_EQ=greater than or equal

home.lang.validator.Cmp.message=Failure: validated value is to be in relation "{prop_rel_cnstr}" to {value}.

Works fine. Almost. The validation message I get looks like this:

Failure: validated value is to be in relation "{home.lang.validator.Cmp.REL.GT}" to 0.

Would anybody please suggest easy and convenient way, how to make Validator recognize and resolve nested {home.lang.validator.Cmp.REL.GT} key? I need it to be nicely usable in JSF2, which handles validation.
I’m not using Spring, but use hibernate-validator 4.

By the way, looks like hibernate-validator 4 doesn’t fully implement JSR303, since later states in the 4.3.1.1.:

1. Message parameters are extracted from
   the message string and used as keys to
   search the ResourceBundle named
   ValidationMessages (often materialized
   as the property file
   /ValidationMessages.properties and its
   locale variations) using the defined
   locale (see below). If a property is
   found, the message parameter is
   replaced with the property value in
   the message string. Step 1 is applied
   recursively until no replacement is
   performed (i.e. a message parameter
   value can itself contain a message
   parameter).

Answer 1

Ok, I did dig into this. The algorithm specified by JSR303 has an unintuitive mess with what (props) are recursively resolvable and what’s not. I think, that’s mainly due to bad distinction in grammar of annotation”s properties and RB’s properties.

So I’ve made my own MessageInterpolator, which you can find in my repo: http://github.com/Andrey-Sisoyev/adv-msg-interpolator. It solves almost all the problems, and also allows to address the resource bundle, where to look for the property.