code: public ExpressionBuilder notNullOrEmpty(final Object property, final String name) {
  
          notNull(property, name);
  
          if (property instanceof String && ((String) property).isEmpty()) {
              messageContainer.addErrorMessage("Property '" + name + "' cannot be empty.");
          }
          if (property instanceof Collection && ((Collection<?>) property).isEmpty()) {
              messageContainer.addErrorMessage("Collection '" + name + "' must contain elements.");
          }
          if (property instanceof Map && ((Map<?, ?>) property).isEmpty()) {
              messageContainer.addErrorMessage("Map '" + name + "' must contain elements.");
          }
  
          return this;
      }
docs: Adds a description for a null or empty property (Strings, Collections and Maps are
  checked for emptyness as well as null-ness).
  
  @param property The property to check.
  @param name     The property name.
  @return This object.