Introduction extensions

Introduction and guideline

General extension rules

DATEX II models can be extended using extensions. The following conditions must be kept in mind:

  • DATEX can be extended with application specific extensions.

  • Extensions are recommended to be done in the UML model. Users are strongly discouraged to manually edit the generated schemas.

  • A level A model can be extended and will then become a Level B if the Level B extensions rules are respected. If not, the model will become a Level C model.

On this level only the extending of enumerations is described. If you want to consult the whole guide click here

Extending Enumerations

  • To extend an enumeration, create a new enumeration by dragging a D2Enumeration from the resources tab, to the extension package or a diagram in the extension package. To indicate that an enumeration is extending an existing element, the D2LevelBExtension UML construct shall be used.

  • The new enumeration extends an existing(Level A) enumeration. In the following example the ExtendedPublicEventTypeEnum extends the existing PublicEventTypeEnum from Level A.

  • To new enumerations it’s allowed to add new enumeration literals.