Now, regarding EEs…
It is noted and agreed that there is some overlap between the concept of External Entity (EE) and component.
The syntactic difference lies in the fact that you must explicitly connect components across interfaces. With EEs, you simply “call them” (invoke their bridges).
Semantically, I could recommend that EEs be used as “common library elements” while components/interfaces contain (and restrict) the application communication.
The example of a math library (a MATH EE with bridges sqrt, sin, cos, etc.) serves to illustrate. It would be a bit “heavy” to ask modelers to explicitly show all connections to such a generally and widely used module.
Like other elements, EEs can be managed in packages. EEs can exist outside of components and be referred to from inside of components (“shared EEs”). EEs can also be private to the internal model elements of a component.
I hope this helps illustrate some of the thinking.
- This reply was modified 7 years, 4 months ago by cort.