While it is not required, it is often seen that people put a ‘Starter’ at the far left of a sequence diagram. With ZenUML, this ‘Starter’ is hardcoded as ‘User’. Many users have complained about that:
- Sometimes ‘User’ does not make sense. A more generic name (such as ‘Starter’) could be better.
- Other users want to define their own starter — such as ‘Client’, ‘Operator’ or ‘Server’.
- ‘User’ cannot be used a normal participant.
We have a few options to define a ‘Starter’. Please let me know which one you like the best and why?
Option 1:
@Starter(User)
Controller.getBook(id) {
BookService.get(Id)
}The default behavior should have already satisfied 80% of cases. This syntax makes the intention clear and specific. It is using a syntax looks similar to a Java annotation. Some users are already familiar with it.
Option 2:
User:Controller.getBook(id) {
BookService.get(Id)
}
// Or
User->Controller.getBook(id) {
...This option is shorter. The : or -> symbol looks like User is talking to Controller. Cons are people can get misled that they are encouraged to use this syntax everywhere (instead of just when starting the sequence).
Option 3:
@User
Controller.getBook(id) {
BookService.get(id)
}Similar to Option 1. Shorter but less clear. @ has become some kind of convention to mention someone. It mentions the ‘Starter’ here.
Option 4:
[User]Controller.getBook(id) {
BookService.get(id)
}It looks more or less like the attributes in C#. I am putting it on the same line because, to me, a ‘Starter’ is NOT very important. It is there just as a complementary entity. Of course, because spaces are not important in ZenUML’s DSL, it would generate the same diagram if you put it on the above line.
I do have my own preference, but please let me hear your opinions first :)
