code: protected PropertiesModel toPropertiesModel(Property[] propertyAnnotations, KnowledgeNamespace knowledgeNamespace) {
          if (propertyAnnotations == null || propertyAnnotations.length == 0) {
              return null;
          }
          PropertiesModel propertiesModel = new V1PropertiesModel(knowledgeNamespace.uri());
          for (Property propertyAnnotation : propertyAnnotations) {
              PropertyModel propertyModel = new V1PropertyModel(knowledgeNamespace.uri());
              String name = propertyAnnotation.name();
              if (!UNDEFINED.equals(name)) {
                  propertyModel.setName(name);
              }
              String value = propertyAnnotation.value();
              if (!UNDEFINED.equals(value)) {
                  propertyModel.setValue(value);
              }
              propertiesModel.addProperty(propertyModel);
          }
          return propertiesModel;
      }
docs: Converts property annotations to properties model.
  
  @param propertyAnnotations propertyAnnotations
  @param knowledgeNamespace knowledgeNamespace
  @return model