docs: public void validate(String path, Schema schema, Object value, List<ValidationResult> results) {
  		String name = path != null ? path : "value";
  		List<String> found = new ArrayList<String>();
  
  		for (String property : _properties) {
  			Object propertyValue = ObjectReader.getProperty(value, property);
  			if (propertyValue != null)
  				found.add(property);
  		}
  
  		if (found.size() == 0) {
  			results.add(new ValidationResult(path, ValidationResultType.Error, "VALUE_NULL",
  					name + " must have at least one property from " + _properties, _properties, null));
  		}
  	}