If use-case A extends use-case B, does that mean A is complete and flow shifted to B or flow will return to A?
Does UML put any restrictions on that? Or does it depend on the modeler?
+4
A:
"extends" in use-case terminology is not a sequential control-flow relationship; "A extends B" means that under certain circumstances use-case A occurs in addition to use-case B. Use-case B can stand alone, use-case A cannot (as it depends on B). Use-case A occurs at an 'extension point' in use-case B.
please review the definitions it sounds like there is some confusion
Steven A. Lowe
2008-11-05 17:30:59
+1: usually we put "Extension Point" in A to show places where it will be extended. And in B we specifically say where and how it extends A. It's just doco -- it doesn't have to compile -- it only has to be clear.
S.Lott
2008-11-05 17:44:07
got it thanks @steven and S.Lott
2008-11-05 18:07:51