Avoid two passes over a list of parameters

I am validating the parameters passed to a series of commands in a file using the following code:

            for (Parameter p : s.getCommand(idx).getParameters()) {
                for (ValidationFactory.TYPES validationType : ValidationFactory.TYPES.values()) {
                    validator = ValidationFactory.getValidator(validationType, errors);
                    try {
                        validator.validate(p);
                    } catch (ValidationException e) {
                        Report.logErrorMessage("Failed to validate: " + validationType);                            
                        continue;
                    }
                }
            } 

Then in the ValidationFactory I have:

public final class ValidationFactory {

public enum TYPES {
    PROPERTIES, 
    PORTS
};

private ValidationFactory() {
}

public static AbstractValidator getValidator(TYPES validationType,
        ValidationErrors errors) {
    switch (validationType) {
    case PROPERTIES:
        return new PropertiesValidator(errors);
    case PORTS:
        return new PortRangeValidator(errors);
    default:
        return null;
    }
}}

This code works really nicely and allows for new validators to be added at a later date. There is one relatively minor problem though.. Each validator iterates over the same list of arguments, so the PropertiesValidator and the PortRangeValidator process the same parameters ignoring parameters that are for the other validator, which means there are two passes over the list of parameters. I would like to do the validation in one pass while keeping the structure of the Factory pattern. I was thinking of putting in some sort of delegator class.. I am using java 1.6 so I can't switch on string arguments which would be nice.