publicfinalclassPersonValidatorextendsDataValidator<Person> {
publicPersonValidator(Personobject) {
super(object);
}
@OverrideprotectedList<String> validate(Personobject) {
returnvalidationBuilder()
.addRequiredField("firstName")
.addRequiredField("lastName")
.addRule(object.age() >= 0, "Age must be a positive number")
.build();
}
}varperson = newPerson(null, "LN", -2);
varvalidator = newPersonValidator(person);
varerrors = validator.getErrors();