While i was thinking about implementing #1162 (comment) for @PrefChange, i realized it it is not easy to implement with existing ValidatorParameterHelper code. Then completely refactoring the class into a fluent API came into my mind. So we can write validations like this:

validator.param.inOrder().required().type(STRING).optional().type(INTEGER).validate(isValid);

validator.param.anyOrder().required().extends(VIEW).optional().type(BOOLEAN).validate(isValid);

I think this covers any possibilities, and with this all pamater validation can be handled by calling one method chain (for example an additional zeroOrOneParameter() call is not needed).