Questions tagged [class-diagram]

A class diagram describes the structure of a system by showing the system's classes, their attributes, operations (or methods), and the relationships among the classes.

Filter by
Sorted by
Tagged with
-2
votes
0answers
36 views

How to add “Result” in an ER diagram?

I created ER diagram and class diagram for my individual stand-alone project named university management system I will attach the ER diagram and the class diagram I have been drown. Actually this is ...
1
vote
2answers
110 views

Combined Inheritance and Composition

Let's say you have a wireless network that acts as a bridge/wireless repeater. How would both factor into a class diagram? In my mind it makes senses to have a parent object that can exist on its own. ...
3
votes
1answer
52 views

How can I provide a class diagram for a system that contains creation of an object that contains a combination of property?

I am designing a system that contains organizational hierarchy management. There are four roles in the system which are the user, admin, manager and head of procurement: I am trying to let the ...
-4
votes
1answer
140 views

Where to put the server in my Messaging System UML diagram?

I try to design a client application for a messaging application. The client can send and receive messages, the client can connect/disconnect. My problem is that I don't know how to incorporate the ...
0
votes
0answers
36 views

CK Metrics - Lower Complexity by Refactoring

I'm suppose to identify 3 CK metrics and the most appropriate class to refactor so as to increase encapsulation, modularity and reduce the complexity of the following project According to my ...
0
votes
2answers
51 views

What is the difference between a qualified association and an association class and how to choose between them?

In UML 2.0, there are two ways of representing an association between classes which I can't seem to distinguish between. First of all, there is the qualified association, represented as such: You ...
0
votes
2answers
65 views

Needs to understand the difference between boundary, controller, logical class types

As the title implies I am trying to understand the difference between boundary, controller and logical class types, which are used in the MVC pattern. I will do so using an example. Please consider ...
2
votes
4answers
74 views

UML aggregation: how can the “whole” exist without its “parts”?

I understand aggregation is a "whole/part" relationship, where the "parent" class is the whole and the "child" class is the part (and this is unidirectional), and that each class exist independently (...
0
votes
2answers
150 views

Simple Poker Simulation - How to design it well

I trying to create a little poker Texas Holdem simulator .. In my solution have some class : Premise : I know about Fisher Yates algorithm. I will implement it later Keep in mind that the next ...
3
votes
2answers
163 views

How to improve this class diagram of a system with its components

So I was given a task of making a class diagram for a bicycle. I know what a class diagram is and the concepts behind one. The requirement is that the bike can brake, turn or speed up. Now to me, a ...
2
votes
3answers
127 views

Is it possible to omit things in the class diagram [closed]

I'm writing documentation for a school java project I'm working on. Basically have chunked most of the methods into the class diagram, but now it seems very unreadable on a pdf as the words are too ...
-1
votes
2answers
205 views

is my UML use case and class diagram correct? [closed]

So I am very new to creating design diagrams. I have a scenario where a user who is an admin of pizza hut selects registration option and the system prompts them to enter customer details. Upon ...
0
votes
1answer
193 views

Navigation in Class Diagram

I know that associations in class diagram can be bi-directional or directional. We refer to this as navigability. I am not sure to fully understand what it means. Please consider the following ...
-1
votes
3answers
84 views

Coherence between sequence diagram and class diagram

Question 1 All participants in a sequence diagram must match a class in class diagram? Question 2 All class that represents some object that is created by the system needs a class that creates it? ...
0
votes
2answers
47 views

Modelling 2 composition relationships between 2 XML elements using UML

I want to model an XML schema that has the following composition relationships: A can contain B, and in another case B can contain A. Using a bi-directional composition is not an option here as it is ...
0
votes
0answers
94 views

Class Diagram Alternative for Qualified Association

I am using PlantUML and it unfortunately does not support qualifiers on a class. I simply want to show in PlantUML that a Task has a qualified association to User through the Task.userID property. A ...
0
votes
3answers
170 views

Diagram to show how one object “becomes” another?

I am working in a purchasing system where we take calls: public class Call { public List<CallItem> CallItems { get; set; } } The calls can be turned into quotes, where call items become ...
0
votes
1answer
85 views

Do I really need to build a class diagram AND a component diagram? [closed]

I'm modeling a system while improving my knowledge of software engineering. I am building a class diagram and a component diagram, but notice that when I tweak one, I have to alter the other. Also, I ...
0
votes
1answer
155 views

Relating subclasses of two classes

Suppose I have the following problem: I have Users who work in Departments. A user can work in multiple departments and a department can have multiple users. Each departament gives to its users only ...
-2
votes
1answer
252 views

UML class diagrams - how do I draw a class diagram that shows a self-reference? [closed]

So I have the following case. I have an interface A and an implementation AImpl. Now I have another implementation of A, called A2Impl, which references any instance of A besides implementing A ...
2
votes
2answers
110 views

What to do with data types with lots of connections in a UML class diagram

I have a Pose data type, consisting of x, y, and rotation values. This being a robotics application, the Pose data type is used in about a dozen places throughout the application. Connecting all ...
1
vote
4answers
283 views

Class diagram for electric guitar and bass

Hi I was recently asked this in an interview to represent a 6 string guitar and a 4 string bass in class structure. I am still new to software design and analysis so was not able to complete the ...
2
votes
1answer
262 views

Ternary association VS association class

I was wondering, are these 2 class diagrams equivalent EXCEPT the fact that in diagram A, a student doesn't have to have a study program? The way I see it - for example in diagram B a study program ...
0
votes
1answer
37 views

What are the differences and connections between UML Profile diagram & UML Class diagrams

I am doing research for developing a software platform and I have created some class diagrams for the platform. My supervisor adviced me to use UML profiles as well to describe the platform in a more ...
2
votes
4answers
97 views

In a Conceptual class diagram, should Abstract Classes and arrowed lines be utilised?

Since we are just describing the problem domain rather than showing how the actual software will be designed, does that mean that we should not need abstract classes to show inheritance and arrowed ...
0
votes
1answer
138 views

How to model an association class in a UML class diagram where only one of the class has access to it?

Given this scenario: "Clinicians can record their own notes for each patient, viewable only by them." I would model it like this: Clinician ----> Patient and "Notes" as an association class ...
0
votes
2answers
223 views

Usage of composition relationship between two class in UML

I'm having quite a difficulty with what i think would suit a Patient class and a Record class in UML Basically the Record class stores the patient's information such as name, vitals, gender, age and ...
0
votes
2answers
157 views

How to model scenarios in UML class diagram?

I'm doing a conceptual class diagram for an app that lets: Clinicians view the patient's lab results and their calculated Reynolds Risk Score. Clinicians make changes to one or more of the patient’s ...
-2
votes
1answer
921 views

Ordered vs sequence in association in UML

I am trying to understand UML class diagrams. Imagine two classes that are related with each other by association. What is the difference between {ordered} and {sequence} for the association?
1
vote
2answers
130 views

Composition - legal class diagram

I wanted to ask if this is a valid class diagram: I tend to think not, because it forces a certain wheel to belong to two vehicles at the same time (because of the 1 multiplicity). If the ...
0
votes
2answers
137 views

2 way multiplicity constraints in code

my goal is to convert this class diagram into Java code. How should I approach this, given that I want the constraints to hold at all times? It creates a chicken-egg problem where the first Course or ...
1
vote
2answers
762 views

How to model attribute dependency “inside one class” in UML class diagram?

I have the following "software reality in working code" (also no access to it): There is a class Class1 with different attributes AttributeA - sums up all "ordinary attributes" EnumType DataType ...
0
votes
2answers
325 views

Convert UML Class to Java Class

Suppose I have 3 UML Class diagrams. One is University, other is College, the other is Department. Each University can have multiple colleges, each college multiple departments. I have the UML class ...
0
votes
1answer
865 views

Why does the Square–Rectangle problem violate SOLID principles?

My previous question was just with class diagram and because of some comments I thought I try to find an example with a little piece of code for the diagram to see if principles correct understood? ...
1
vote
2answers
687 views

Which SOLID principles are broken by this class diagram?

I just read about all the 5 principles S,O,L,I,D and I like test it in little example if I understand them correct. Which SOLID principles are hurt by this class diagram? I think what is broken is ...
1
vote
2answers
320 views

When converting the ER into the class diagram, what happened to the Weak Entities in the ER diagram

I am trying to convert an ER diagram into a class diagram. Below image is showing that part of my ER diagram and which contains a weak entity call 'Parent'. Therefore when we consider the ER diagram, ...
1
vote
0answers
304 views

UML Class Diagram HashMap with different Key datatype using Qualified Association

By using the qualified association element of UML Class Diagram, we can create HashMap as the datatype of one of our class attributes (see here). In my case, I have to use HashMap with different key ...
-3
votes
1answer
2k views

UML Class Diagram HashMap Data Type

How can I show a Java HashMap data type in UML Class Diagram (or C# dictionary)? I.E. This class: public class Test { private Map<String, String> map; private Map<String, int> ...
1
vote
1answer
2k views

UML Class Diagram with reference data type

For the following UML Class diagram, I have a reference data type Nurse, and I am using it in Hospital Class, is it needed all the time to describe the reference data types in UML Class diagram? Is ...
3
votes
1answer
347 views

Can you place elements other than classes in a class diagram [closed]

I'm currently doing up class diagrams for a project I'm working on. I feel there's something that should be represented in my class diagram but I'm not quite sure. I have a .csv file which the ...
1
vote
1answer
189 views

Role design pattern in uml

In my UML class diagram, I have an interface called Contract which a Staff implements. There are two types of Staffs: one is partTime and the other is fullTime. Does that mean that the two partTime ...
0
votes
1answer
158 views

Class Diagram for Train-Wagon Senario

I have doubts on approaching doing this. I have a Train class and a Wagon class. There are three types of wagon: FirstClass, TouristClass and DiningCar. Each of these types has the same properties ...
2
votes
4answers
727 views

Is actor a own class

I have this sequence diagram and want to transform it into a class diagram. But I don't know if the actor (Customer) is in this case a own class or not. Normally the actor isn't a own class, but in ...
5
votes
4answers
10k views

How to represent constants in UML class diagram?

I am working on developing a UML class diagram from C++ code. I have a classless header file that is basically a definitions file (it has structs, enums and defined constants). I know how to ...
2
votes
2answers
320 views

Should I show the association class in my class diagram?

For example I have a relationship like this: user (0..*) buys product (0..*) Which results in an association class, called sale, which has the userID and productID. Just for the question's sake, ...
3
votes
3answers
4k views

UML Class Diagram: How to describe method functionality?

Recently, we have learned about UML class diagrams in university and I began applying that knowledge to my work projects. However, I am still unsure how or where I am supposed to describe the ...
0
votes
1answer
597 views

Should I make a separate class diagram for the administration part of my software?

I am building a software which has two types of users in it: main users and admins. I am still building the class diagram for this system. For the main user's relations I have things like: user ...
3
votes
1answer
9k views

How to model user management using UML class diagram?

I have school project where me and my team have to build a health care system. It consists of different modules including : A module for doctors : It allows a doctor to access the medical records of ...
3
votes
1answer
964 views

Association + multiplicity vs aggregation and composition?

I know the differences between these associations (as described here). However I'm wondering: Composition, why not simply use an association with multiplicity of 1..* (and thus implicit saying that ...
3
votes
3answers
176 views

Can a parent class not have attributes or functions?

I have 3 Different Classes Which are representing different types of Sensors, for example: WaterLevelSensor DoorSensor TemperatureSensor Each Class has different functionality. Following the OOD ...