UML object attribute linkage - uml

If you've got a function like this inside a class called 'A'
public updateResponse(UpdateRequest updateRequest){
//...
}
Where UpdateRequest is another class which you create an object from
as in UpdateRequest ur = new UpdateRequest();
What is the relation between those two classes (Between 'A' and 'UpdateRequest')? I thought of an "usage" link between the interface of A and the class UpdateRequest. Is this correct? If not, what kind of link should it be?

If the diagram is a class diagram there is no relationship to be taken from your question.
The relationship between these two classes would be best show in a Sequence Diagram or an Activity Diagram. These show method calls etc, a method may be a member of a class in a class digram but it wouldn't really be expressed as a link. Unless you specifically wantto highlight this method, you could then put a usage link to the method on the class. But its not always good practice to do this for every method as you end up with a very messy class diagram.
It's always best to show these relationships in the diagrams you have to show the usage of the method.
EDIT:
How does the class A instance relate class UpdateRequest instance?
Q - What relationship are you trying to show? A - Method/function call.
Some class calls updateResponse and the information flow is an UpdateRequest instance.
Therefore... From left to right
SomeClass --| A
| | a = new UpdateRequest |
|<-----| |
| |
| updateResponse(a) |
|------------------------------------>|
Your sequence diagram might look something like this. There is no specific relationship drawn between class A and UpdateRequest as it is simply a piece of information that flows through the method call you have in your example. If the class was a member of the class, then the relationship would be shown directly on a class diagram, not applicable here. All the classes might (should) shown on a class diagram seperately, this can then be used as a reference point about all the objects in any diagram for those that need to analyse the design.

Related

Add Association Class to Composition relationship

I'd like to know if it is correct to add an Association Class to a Composition relationship?
For example (see figure below), can I add an Association Class (i.e. NameValue class) to the composition relationship between Name class and Value class? One Name can have multiple Value and one Value can only be attached to one Name. NameValue class stores the name-value pairs.
The reason why I create the association class (i.e. NameValue class) is that I need to create associations/relationships between NameValue class and other classes such as Class A.
If the answer is yes, is it recommended to turn the association class into a normal class?
Many thanks!
I'd like to know if it is correct to add an Association Class to a Composition relationship?
yes in an association-class the association can have an owner-end property being a composition, in formal/2017-12-05 there is nothing in § 11.5.3.2 Association Classes starting page 200 nor in § 11.8.2 AssociationClass [Class] against that even association-class has some constraints
NameValue class stores the name-value pairs.
note this is absolutely not the goal of the class of an association-class in UML, and not necessary the case when you implement an association-class
The reason why I create the association class (i.e. NameValue class) is that I need to create associations/relationships between NameValue class and other classes such as Class A
because NameValue is used at implementation level to stores the name-value pairs and then to implement the association(-class), in UML the diagram you want is :
(NameValue does not exist at UML level but only at implementation level)
If the answer is yes, is it recommended to turn the association class into a normal class?
At UML level the association-class do not exist for nothing, they make the model clear, so I do not recommend to not use class-association (but this is of course opinion-based)

How can I add a simple generic type annotation for a dictionary in UML?

In a UML class diagram, the value of one of the attributes of a class is a (typed) dictionary. What is a proper UML type annotation? (Within the box; not as an association.)
For example, in Python I would annotate this attribute with Dict[A,B] or possibly Mapping[A,B]. I am not asking about Python; this is just one example of a somewhat generic attribute annotation. I am open to the possibility that UML does not offer a language agnostic equivalent to this, but I am hoping that is not true.
Comment: I am asking about generic attribute annotation, directly with the class box. I do not wish to add a separate class box for Dict to the diagram. Therefore this is not a duplicate of How can I represent a Python dictionary in UML?
In UML Dict is typically model as a template class with two template parameters for instance named key and value.
Let's say you want the class C has the attribute a being a Dict[A,B], so you have a binding having the template param substitutions key -> A and value -> B.
There are several ways to show that in a class diagram.
For instance using the class DictAB to model Dict[A,B] :
or if you prefer :
But it is also possible to not use the auxiliary class DictAB and to use the textual representation of the binding expression (see formal/2017-12-05 § 7.3.4 page 26) :

UML class diagram design

I am trying to implement the UML class diagram for the first time. This is the class diagram which I have been work through:
This is the requirement:
I do not expect anyone do it for me, but I think I need someone help to check where I can improve or I anything is missing. Thank You.
A class diagram is a structural diagram. Behaviors (e.g. adding, deleteing, etc...) shall not appear therein, except if you decide to make them operations of one class.
Here how to understand the requirements:
R1. Classes GroceryList, Item and User. Association between 0..n GroceryList and 0..n Item. Association class with property Quantity
R2. Class ItemType
R3. Association between 0..n Item and 1 ItemType. Both classes have a property Name
R6. Association class also has property CheckOff
R10. Association between 1 User and 0..n GroceryList. GroceryList has a property Name
Assumption: User has a property Name
If your teacher never told you what an association class is, then use a class ListItem instead, with an association of 0..n ListItems with 1 Item, and a coposition link from GroceryList to ListItem
Remove any other box in your diagram, because these are either behaviors, or a duplicate of an existing class.
For the operations, it is not clear to me because it depends on the architecture of your application (e.g. will you use repository classes?).

Any modifications i should do on this class diagram?

I'm working on a class diagram of a simple project.
Here's a basic description of it:
"usuario" is the 'user class'. From it, i can have "membro_coral, "Membro_comissao" and "Administrador". "membro_coral" can post some news on the web site, but it goes through an avaliation to see if it can be posted or not. "Membro_coral" has a "perfil" associated with it.
There's the "evento" class. It's a class for mapping events. Users can give their disponibilities to attend to some events. And "escalacoes_disponibilidades" is the junction table.
I've added Three classes corresponding to the "Perfil" values. Some people are "membro_comissao", some people are "membro_coral" and actualy, only one is the "Administrador".
Is this class diagram right? Any modifications i should do?
EDIT: i've update my class diagram. I've added the "Status_Noticia" class. It's associated with noticia. I've done this in order to improve the statemachine diagram of "Noticia" (there's an use case which an user can send news to de displayed, but it goes through an avaliation process).
It's mostly correct. There are some minor observations however:
Membro_comissao, Membro_coral and Administrator are kind of users, right? If so, you should do one of the following: a) derive all 3 classes form user, or b) create a new class (enumerator) TipoUsuario, with those 3 values. Which option to implement depends on if there are some special features that make the 3 different one from another (some different attributes, methods or maybe associations (see the next point)
You said: " "Membro_coral" has a "perfil" associated with it.". Than this class should be associated with PErfil and not otherwise. This could be a reason to apply the option a) from before. This association should be a normal assoc. and not a composition
So, the main decision you must take is how to model user types.

How to draw a relationship between a property and a class in ArgoUML?

In ArgoUML, I have the ability to put a class Type to any property of a class. For example, I can declare a customer property with a Customer type in the Order class.
I can also easily draw a relationship from class to class:
But I can't figure out how to "draw" the link from the customer property to the Customer class. The link is never really connected to the property, but rather to the entire Order class.
I can move the position of the link manually:
But it's never really "locked" to the customer property, and can be moved automatically by the software at any moment.
Is there a way to do this?
You can not have an association in UML which is not connecting the entire two classes. It is not possible to touch the property inside the class.
Workarounds are:
add a note linked to the property
add an icon to the property which would be designed like an association.
I don't know if this advanced icons customization is available in this free tool but it is in other tools.
I found a flash demo which shows the association attribute with an icon. Look at : http://www.download-omondo.com/show_association_member.swf
If you need to understand what mean an association in UML and code generation in Java then have a look at this demo: http://www.download-omondo.com/association.swf
Hope this help.
ArgoUML follows the UML specification. Associations are drawn from one class to another. Attributes are drawn inside the 2nd compartment of a class.
The association type closest in meaning to an attribute is composition, but they are not equivalent.
You should never portray something AND as an attribute of a class, AND as a separate class associated to it.
E.g. 1. an Order may have a Number, that may be used by the customer to identify his Order. The Number is best portrayed as an attribute (in the 2nd compartment of the class).
E.g. 2. an Order may be associated to the Customer who placed the order. The Customer is best portrayed as a separate class, since it has its own lifespan (behavior), associated with the Order. This allows to show multiplicities and roles at both ends of the association line.

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