Some issue on sequence diagram you should know
procedure dispatch foreach (lineitem) if (product.value > $10K) careful.dispatch else regular.dispatch end if end for if (needsConfirmation) messenger.confirm end procedure
1.Each participant is an instance initated by class entity in class diagram
2.Lifeline can be started with newing an instance of object, can be delected by self or other objects.
3.Activation can define spending time of the operation of the participant . It also can define all processes in some operation.
4.By designing Operators(like loop, alt, opt,etc...), sequence diagram can let model and code more closely.