Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
I can’t understand what a qualifier is in UML.
For example, in the scanned page, there’s a qualifier named
“SharedRegister” that has “state” and “plateNumber” in it.
Why not just used a class called SharerRegister and put “state”
and “plateNumber” in it? What does it offer over a class exactly?
(Image from Schaum’s Outlines, UML 2nd edition. Simon Benett. Pg 108)
stateandPlateNumberact like a key with which the related class can be accessed. If you didn’t use a qualifier you would have a relation between the classes with multiplicity of * but would not know exactly how they are related. Here, you know that classShareRegister, by knowing a specific value forstateandPlateNumbercan access 0 or 1 instances ofCarSharer.