code: public void validateConstraints(Entity entity) {
  		for (String propertyName : requiredProperties) {
              Object value = entity.getProperty(propertyName);
  			if (value == null || (value instanceof String && ((String) value).length() == 0)) {
  				throw new RequiredFieldException("Required property '" + this.persistentClass.getSimpleName() + "." + propertyName + "' is not set");
  			}
  		}
  	}
docs: Validate the schema constraints on the provided Entity instance
  @param entity the entity to validate