class GetHBase extends AbstractProcessor {

    @Override
    protected Collection<ValidationResult> customValidate(ValidationContext validationContext) {
        final String columns = validationContext.getProperty(COLUMNS).getValue();
        final String filter = validationContext.getProperty(FILTER_EXPRESSION).getValue();

        final List<ValidationResult> problems = new ArrayList<>();

        if (!StringUtils.isBlank(columns) && !StringUtils.isBlank(filter)) {
            problems.add(new ValidationResult.Builder()
                    .subject(FILTER_EXPRESSION.getDisplayName())
                    .input(filter).valid(false)
                    .explanation("a filter expression can not be used in conjunction with the Columns property")
                    .build());
        }

        return problems;
    }

}