UML14 — Remove uses of multiple inheritance from UML meta model

Issue: Remove uses of multiple inheritance from UML meta model. For instance, LinkClass inherits from Class and Association. At least, remove it from the physical (XMI) meta model.

Rationale: This is based on a practical argument, rather than a theoretical. Many modern programming languages, most notably Java, do not support multiple inheritance, which makes it difficult to implement the meta model correctly. To spread the use of UML it is important that tool vendors can do this. The meta model is already defined in a minimalist subset of UML, it just needs to be a little bit more minimal. It’s not as if multiple inheritance is absolutely necessary, a lot of people do just fine without it.

rejected