private static void registerTagModifiers(BeanValidationConfiguration configuration) {
configuration.register(Size.class, new ParsleySizeTagModifier());
configuration.register(Min.class, new ParsleyMinTagModifier());
configuration.register(Max.class, new ParsleyMaxTagModifier());
configuration.register(NotNull.class, new ParsleyNotNullTagModifier());
configuration.register(Pattern.class, new ParsleyPatternTagModifier());
if (HV_EMAIL_CONSTRAINT != null) {
//this is only added if hibernate validator is in the classpath
configuration.register(HV_EMAIL_CONSTRAINT, new ParsleyEmailTagModifier());
}