I have an OPT (Optional) fragment in my sequence diagram and I wanted to draw it on my collaboration diagram but unsure if there is such a thing as OPT fragmnet in collaboration? I googled and couldn't find any solutions.
One of my friends told me to use: [condition]: someFunction()
But I don't know if that is correct way
A communication diagram (that is the official name) is just one of the four possible views on an Interaction (the others being sequence diagram, timing diagram and interaction overview diagram). Each of the diagrams will show different aspects of the Interaction. So, an optional Fragment will be shown as a frame in a sequence diagram and as a guard on the message label of the first message contained in the fragment in a communication diagram. Since the connection between the messages is only deducible by the hierarchical message number, it is harder to see this connection. On the other hand, it is easier to see the network of connections between the participants of the interaction in a communication diagram.
Related
The picture is taken from the book "UML # Classroom". The text says "the registration is via e-mail, that is, asynchronous".
In actuality, I believe, there would be no "Student" and "Professor" objects involved in the process. Rather an interface, a call to a mail server and in general, nothing that would tell the viewer of the diagram what is really going on.
That makes sense to me because it has an illustrative purpose. The methods of the classes in the sequence diagram would only resemble the methods in a class diagram at a low level.
If I am tasked with a high level view of class diagram and high level sequence diagrams of a particular interaction, if I am then asked why the classes of the class diagram don't have any of the methods of the sequence diagram, am I right to say that they simply don't have to?
Should I reach a compromise with the sequence diagram wherein I try to make the calls similar to what will be going on in the program?
The methods of the classes in the sequence diagram would only resemble the methods in a class diagram at a low level.
Not necessary, all depends on the goal of the sequence diagram, you can have classes at design level (may be allowing to generate code) but having them in a sequence diagram giving a semantic (high) level. You can also show these classes in class/package/... diagrams without low detail so not at design level.
The only rule is to have diagram saying something useful, and following UML specification of course. Do not forget UML is not a method but a language, it does not indicate how it must be used.
Remark you can put note in a diagram to help saying explicitly its level/goal in case you are afraid it is confusing because not 100% limited/dedicated to design even using classes part of the design.
if I am then asked why the classes of the class diagram don't have any of the methods of the sequence diagram, am I right to say that they simply don't have to?
yes, because the goal is not necessary to show a sequence of calls but for instance a higher level.
Should I reach a compromise with the sequence diagram wherein I try to make the calls similar to what will be going on in the program?
Of course you can do too.
Notice a sequence diagram (so in fact an interaction) has limited features, while for instance an activity allows to model a behavior in detail without the same limitations.
I'm designing some Sequence Diagrams for my project and decided to divide login and register use cases, creating two different diagrams (thought was a wise choice to separate concerns and simplify).
Now, when Register process is finished, I would like to tell the diagram to follow some path inside Login Diagram. Is that what Lost message is for? Like calling an event outside the diagram? Please clarify.
This is a Gate. UML 2.5 Specs:
17.4.4.3 Gate
Gates are just points on the frame, the ends of the messages. They may have an explicit name (see Figure 17.4).
17.12.9 Gate [Class]
17.12.9.1 Description
A Gate is a MessageEnd which serves as a connection point for relating a Message which has a MessageEnd (sendEvent / receiveEvent) outside an InteractionFragment with another Message which has a MessageEnd (receiveEvent / sendEvent) inside that InteractionFragment.
I have build a usecase diagram for hotel reservation
Should i build a sequence diagram for each usecase in the usecase diagram, or can i summarize multiple usecase in a single sequence diagram?
A use case diagram shows how use cases and actors relate to each other and gives a usefulness system overview. Use cases boil the system down to their added values and do not show how these are achieved.
Any scenario of a use case is graphically represented in an activity diagram where the single steps occur as actions.
A sequence diagram is used to show how objects communicate.
Usually you derive classes and relate them to actions of the use case activities. So when you create a sequence diagram it highlights a certain aspect of the whole system. This highlight is usually spot on and not a floodlight. Putting multiple use case scenarios in a single SD would for sure simply blind any reader instantly.
Usecase diagram
Use case diagrams show business use cases, actors, and the relationships between them. The relationships between actors and business use cases state that an actor can use a certain functionality of the business system. You will not find any information about how or in what chronological sequence these services are rendered
sequence diagram
A sequence diagram can map a scenarios described by a use case in step by step detail to define how objects collaborate to achieve your application's goals.
Here is the diagram , which will clear things better to you
I would like to know if we can use 0..* in a UML sequence diagram.
Incase if we can , could anyone please explain what does it mean in the perspective of a sequence diagram?
Take a look at the use cases of sequence diagrams from this link. It is stated that:
A sequence diagram shows an interaction, which represents the sequence
of messages between instances of classes, components, subsystems, or
actors. Time flows down the diagram, and it shows the flow of control
from one participant to another. Use sequence diagrams to visualize
instances and events, instead of classes and methods. More than one
instance of the same type can appear on the diagram. More than one
occurrence of the same message can also appear.
One to one, zero to many, one to many etc. are class diagram relationship indicators and you can not use them in sequence diagrams because they are irrevelant.
Also, you may want to take a look at this link
As i read through UML specification superstructure that there is sequence diagram and there is a collaboration diagram
so,What is the differences between
sequence diagram and collaboration diagram?
Sequence and collaboration diagrams both aim at describing the dynamic interactions between objects.
The information you can describe are basically the same, but the two models have a different focus:
Sequence diagrams highlight more the temporal aspect, by showing invocation and responses along a (vertical) timeline and by explicitly showing the activation time of objects.
Sequence diagrams show how objects communicate with each other in terms of a temporal sequence of messages. The time flow is the most visible aspect in these diagrams, as messages are sequenced according to a vertical timeline and also the lifespan of objects associated to
those messages is reported. The figure below (taken from our book) shows an example of a sequence diagram describing 3 objects (instances of classes Shipment, Invoice and PartList) and the messages exchanged between each other. Interaction diagrams describe execution scenarios of the system.
Collaboration diagrams aim at showing the communications that happen between objects, by defining messages that flow between each other. They basically consist of superimposing the communication actions upon an object diagram. The temporal aspect can be shown here too, by numbering the interactions with sequential labels.
A collaboration diagram shows the interactions between objects or classes in terms of links (solid undirected lines connecting the elements that can interact) and messages that flow through the links. This describes at the same time some kind of static structure (links and nodes) and dynamic behavior (messages) of the system. An example is shown below.
UML1: These diagrams are the same, but present data from different points of view.
UML2: The Collaboration diagram is renamed to Communication diagram (there were misunderstanding since people thought that Collaboration diagram was used to show collaborations).
These diagrams are almost the same, but present the Sequence diagram has much more possibilities for visualization (for example, combined fragments, state invariants).
Sequence diagrams specify interaction in a time sequence manner which may be among objects and/or classes. These diagrams are created during early elaboration phase where each flow of the use case is defined in terms of sequences , i.e. after each step what is going to happen next. This kind of representation is very helpful to understand & discuss the use cases with the customer, where both can come out with all possible functional aspects.
On the other hand collaboration diagram provides a direct interaction among the object. These diagram seem to used more in the design phase of the development when you are designing the implementation of the relationship.
There is a difference between sequence diagrams and collaboration diagrams. Sequence diagrams shows object interaction in timely manner(so no need of numbering the messages). But collaboration diagram doesn't show object interaction in timely manner. (need to numbering the messages).
NOTE:
Now Collaboration diagrams are also called as communication diagrams.
A Sequence diagram is dynamic, and, more importantly, is time ordered. A Collaboration diagram is very similar to a Sequence diagram in the purpose it achieves; in other words, it shows the dynamic interaction of the objects in a system. A distinguishing feature of a Collaboration diagram is that it shows the objects and their association with other objects in the system apart from how they interact with each other. The association between objects is not represented in a Sequence diagram.
Link : http://www.developer.com/design/article.php/3102981/Collaboration-Diagram-in-UML.htm
Use sequence diagrams to show time and to emphasize the sequence or
the ordering of the interactions.
Use communication diagrams to emphasize the links among the
participants. Communication diagrams can be a helpful supplement
to the object diagrams.