After having my use case diagrams, i can't found the logique to follow to implement the sequence diagram, how can i go from analysis the what to design the how from the actors and uses cases to a sequence diagram with many stereotype without thinking about the class diagram (to respect the order).
Or should i have to implement others diagrams to passe from the use case one to the sequence?
I've always created class diagrams and sequence diagrams together (and, at least, the UML modeller Sparx Enterprise Architect is compatible with that point of view), but I was never educated in the proper order if such a thing exist.
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I want to verify that i correctly understand the rational unified process.
My understanding is:
For the requirements specification activity, i have to design the use case diagram (a general one), the class diagram (classes, attributes, relations), and a general sequence diagram.
For the analysis activity, i have to design a detailed use case, the sequence diagram (using control, view and model classes), the analysis class diagram, the collaboration diagram
For the conception diagram, i have to design the class diagram and the deploiement diagram
is that correct please?
for my questions:
When can i use the activity and the state-transition diagrams?
Is it correct to first design a class diagram in the requirement acquisition phase?
In the implementation phase, which diagrams do i have to use? Or do you only have to generate code from some diagrams?
thank you a lot !!
Your assumptions are right.
ADs are used to illustrate scenarios from a use case. State transitions are usually created for classes. The can be used in code generation.
Not really. To sketch a class diagram of your solution you need a rough idea how that could look like. Just taking it from requirements works only for simple systems. You need to go through the use cases first to settle a usable construct.
To implement a system some class diagrams are essential. SDs help the coder to see how the classes collaborate. You can not generate code from that. Only code stubs from classes.
Is there any difference between uml diagram and a use case diagram ? Since both the diagrams are made differently but both show the same information
I think you are getting confused with the UML and use case.
UML contains different diagrams and Use case is one of it. Use Case diagram defines Behavioural component of Software Design i.e. Actor communicating with the system through Task - Use Case.
UML also contains Structural diagrams as well as - such as Class Diagram.
From what I can understand UML is a superset and USE case is subset.
According to UML context diagram context diagram doesn't exists.
So my question is which one of UML diagrams is good to show something like this and how to paint this?
I've just found the following definition: http://en.wikipedia.org/wiki/System_context_diagram
That's probably what you need. :)
A context diagram defines a boundary between the system, or part of a system, and its
environment, showing the entities that interact with it.
There is no single diagram in UML that would map to this definition, but I have some good news - there are several diagrams (out of total of 14) that can show the frontier between the system and its surrounding world from different perspectives. This is much more flexible than only a context diagram.
First of all, I would mention a special UML element - a boundary. It can be used in any diagram type to show some kind of delimitation. You might want to optionally use it to visually delimit between the system and its environment, especially in situations when this is not explicit.
The following diagrams can show the boundary between the system and its environment:
Use case diagram (your example) support the context explicitly on the functional level. Use cases are elements of the system under development, while the actors are extern entities (systems or human users). Before mentioned boundary is often used to visually delimit between the system and its environment.
Component diagram is used to model some kind of software modules (applications, DBs, external systems, libraries, etc). You can use it to show both internal and external components and the way they interact. A boundary can be used to clearly draw the separation line.
Activity diagram can show your system/business/usage processes. Some activities can be performed internally, others externally. Here you don't need the boundary, but the so called swimlanes to depict who does what.
Sequence/collaboration diagrams are another option. They show the communication sequences between several objects. If you split those objects in internal and external ones and wrap them up with the boundaries, there is another context diagram. :)
UML is flexible, there are probably further options, but I think this is enough to get the idea.
Names of your association are services. UseCase in center of diagram is context of services definition. See usecase diagram:
It could be done with a use case
http://en.wikipedia.org/wiki/Use_case
EDIT:
Reconsidering it, use case diagram should be the next step once the operations are defined so first you shouls make a system sequence diagram.
http://en.wikipedia.org/wiki/System_sequence_diagram
If you're happy with going into the not complete superset of UML that is SysML, you can have proper Context diagrams there.
However, context diagrams in SysML are simply Block Diagrams showing system context… and Block Diagrams happen to be the same as UML2 Class diagram, where the classes are of stereotype «SysML::Block».
So you can define your context diagram in terms of aggregation of blocks to your system, with the relevant stereotypes, basing it on UML2 Class diagrams.
I tend to use collaboration diagrams for this. So for each major scenario of each use case, draw a collaboration diagram showing the actors, with the application as a single entity in the middle, and messages travelling around that show how the application interacts with the actors in order to fulfil the scenario.
(I don't put too much detail in the messages -- I only want to show that there is a delegation of responsibility and some kind of interaction, but I don't care about details of actual messages, views, data etc.)
I find the context diagram does have a particular appeal. It sits well with business users, showing them the scope & parties of a system in a very easy way. So, I tend to create a context diagram, even in contexts where UML is prevalent.
As we known . The sequence diagram in UML is a kind of interaction diagram that shows how processes operate with one another and in what order Between the Class or Object.
Now I am trying to find a diagram in UML or some tools to describe interaction and operation order of distributed system. Is there any diagram or tools which model the interaction between Distributed system like sequence diagram ?Thanks.
Activity Diagrams are the UML diagram to use in this situation.
Wikipedia Activity Diagram
Agile Activity Diagrams
Sequence and communication diagrams aim to show how "things" interact. These "things" could be objects, components or complete systems
You can also use sequence diagrams to describe interaction between components in a distributed system, each lifeline designating one of the system components.
What's the difference between sequence diagrams and scenario diagrams in UML?
I think you mean System Sequence Diagram (SSD) and Sequence Diagram.
The purpose of SSD is to illustrate a particular use-case scenario in a visual format where the system appears as a black box.
Sequence Diagram, on the other hand, shows how system objects interact over time for achieving a particular scenario of a use-case.
"Scenarios" per your link aren't diagrams, they're narrative text. They're also called "Use Case Narratives" among other terms. They are approximately equivalent to other behaviour specifications (sequence diagrams, activity diagrams).
There are generally three differences:
Format. Scenarios are textual, sequence/activity diagrams are, well, diagrams
Content. Textual narrative is often used to describe the sequence of interactions between the user and the "system" in Use Case descriptions. Hence there are usually only two participants (User & System). In contrast, sequence diagrams are primarily used to show how behaviour is distributed among objects. Consequently there will usually be more than two participants.
Formality. Narratives are often used earlier in the cycle to get an idea of what's needed. Consequently they're often less formal than Sequence diagrams - which typically show inter-object messages ("method calls").
For examples of tools that do this, take a look at websequencediagrams.com. Or search for "free UML tools".
There is no diagram type called scenario. Maybe you are thinking of collaboration?
Sequence and collaboration diagrams are actually the same: the Sequence depicts the chronology while the Collaboration depicts the interactions between the collaborators. Together (a tool that was around a decade ago) used to let you literally just change the setting and see the diagram in the other mode.
I use OmniGraffle (Mac). It's great for class diagrams. Has support for Sequence diagrams but not Collaboration.