What is an integrated class diagram? what is the difference between a class diagram and an integrated class diagram? I have searched on google and youtube but could not find a proper explanation.
There is no notion of "integrated class diagram" defined in the UML specifications, and it's not a popular term if you search in specialized publications.
Unless you are learning a custom modelling technique inspired from UML, the term "integrated" shall therefore be taken in its usual system engineering sense: assembling parts together to make a working whole.
Applied to a class diagram, this would mean to either consolidate several models into a single one (e.g. for the purpose of integrating sub-systems), or assembling model parts (e.g. if you have separate class diagrams each focusing on specific parts of a system, and then want to show the big picture and how these groups of classes relate to each other).
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I had been doing some UML class diagram examples from the recent exams for my software design course, and I found one where it says:"Design a class model for a specific problem, by using MVC and STATE pattern, but no need to include getters and setters." Is this the same thing as the regular class diagram? I've been googling and I found nothing UML based by searching for class MODEL.
The model is abstract. A diagram is a view on the model. UML offers a number of different diagrams. There are mainly two categories: static and behavioral. Class diagrams fall under the static category and they show how the classes in the model are related to each other. You can create multiple class diagrams like one with all classes (assuming that you have a rather limited number of classes) and/or one per class with that in focus. Or you have sub-domains with related classes placed in one diagram. The behavioral diagrams shed light on how class instances communicate with each other at run time.
As a side note you can think of it in terms of Platon's Cave Allegory. The diagrams are the shadows of the real world projected by a fire to the wall you can see from you chained position.
"Design a class model" means: "Create one or more class diagrams that together form a consistent model".
A model in computer science is a graphical representation of (a piece of) software or of (a part of) the business domain in order to help people know or understand the subject the model represents (see wikipedia). This graphical representation may consist of one or more diagrams.
Can someone explain me the difference between class diagram during analysis and design?
So far, I understand that the class diagram of design would be the real class diagram, with all methods and attributes (ready to become code), but what about analysis? Do I have to do a class diagram for every sequence diagram? Do I have to add methods and attributes at the design stage already ? Or only connection?
The UML class model is produced and refined iteratively as the understanding of the system increases. There's only one model for your system, although different diagrams may outline different aspects and level of details of this model.
Typically you would start with the domain model based on the requirements (e.g. use cases, user stories, statement of work, user interviews, etc.):
Top priority is to get an overview. So the first sketch would identify the domain classes and how they relate to each other.
You would then enrich this initial understanding by outlining in the diagram the key properties and methods that are essential to the understanding of the domain.
You would then enrich the model with more detailed design diagrams as you design your solution. So you would add any classes required for the implementation (e.g.user interface classes, application controllers, persistence layers, etc.).
Design diagrams are used to get a shared understanding about the software structure within the development team. So they should be easy to understand (i.e.focus on important aspects and not necessarily be cluttered with too many details that would anyhow have to be implemented in code and quickly be outdated if you don't have an army of analysts to update the model).
If you'd use an UML tool able to generate code or if you are contractually obliged to provide all the details in UML form, you would further refine the model with a fully detailed implementation diagram. Attention: for scholar work it is frequent that the teacher asks for a design diagram but expects in reality an implementation diagram.
We have 3 major types of class diagram in Object Oriented Methodologies.
Class Diagrams in Requirement (Domain Modeling)
Analysis Class Diagrams
Design Class Diagrams
Main difference of these class diagrams is their Abstraction.
In Domain Modeling, we use Class Diagrams. BUT, we do not use any Inheritance or any Interfaces, or any preforming analysis on the classes. We just write so little attributes of classes (about 3 attributes). we don't write any methods of classes. WHY? because of Abstraction. Main goal of Domain Modeling is modeling the domain. And detect Which classes should be in problem domain of system.
In Analysis modeling, we use class diagram. Classes in analysis is more detailed than classes in Domain. But it is not the final specification.
In Analysis, we determine Analysis Classes. We can use Inheritance between them. We can write their attributes and methods in detail. BUT, this phase is done by System Analysts. (Not System Designers or Programmer). Their profession is both knowing the Business Logics and Software Techniques. So they can write analysis classes in more detailed than Domain. However, they can not write very detailed as System Designers can.
In the other hand, we can use some analysis patterns to determine our Analysis Classes. For example RUP introduce Boundary/Control/Entity pattern. If we decided to use an existing analysis pattern, we can use the guidelines exist in the pattern documentations.
The guideline of Boundary/Control/Entity about the abstraction of classes are in this reference. In this pattern we should write only attributes for Entity classes and write only methods for Control classes and write attributes and methods for Boundary classes.
However, In my idea, we can follow the guideline or not. We can write more attributes and methods for analysis classes. What is happening? If our System Analyst try to write more detailed attributes or methods, what's happening:
I think that 1) our system analyst is not system analyst. maybe system designer. 2) we don't need their details. It is just time consuming for analysis phase. 3) ONLY if our analysis and design team are the same, or we combine analysis and design (like Agile Methodologies) the details in Analysis can be logical and useable.
In Design modeling, we use class diagram, this type of class diagram should be the final specification and should contain all attributes and methods. This classes are not conceptual. we can use all OOD technologies, Design Pattern and etc.
I'm working on sequence & class diagram for education website, should all objects in sequence diagram be a class in Class diagram?
For example in sequence diagram for registration process I need an object called "Data Base" which needed for saving information of user, should "Date base" be a class in class diagram? and what can be its functions? Is it just load & save?
I think it depends on the level of formality, abstraction, and the purpose of your UML model.
Martin Fowler talks about UML as Sketch, UML as Blueprint, and UML as Programming Language.
The terminology has gotten some good usage; and I think 'UML as Sketch' in particular has emerged as a popular mode, with the goal of human-to-human communication about the design of a system; not necessarily a formal engineering specification (i.e. a blueprint), nor suitable as an input to a code generator (i.e. a programming language).
If you want to use UML in Sketch mode, which is perfectly valid, then it's not a requirement for your sequence diagrams to use only the classes defined in your class diagram. In fact, some of the objects/lifelines in a sequence diagram aren't class instances at all:
They may be "actors" defined in a use case diagram (or not). Actors are often people, and as such are represented as stick figures. "End user" is a common actor to include in a sequence diagram. Plenty of examples here.
They may be external systems, like a database, that are not defined in your class model. Your system might have a class, or set of classes, to abstract the database, i.e. a "data access layer" or DAL. But then again, your system might not have a DAL; and even if it does, you might still want your sequence diagram to show the interactions across the boundary, between the DAL and the actual database.
Using UML as a sketch, the methods implemented by external actors or system components are really up to you. You could show a database query as execute query, or something more specific, like an actual SQL statement. The "correctness" of your diagram is in its ability to communicate effectively with your audience, at the right level of detail and formality.
Yes, the Database would be a class in Class Diagram and its functions can be validation() , generatingErrorMessage() etc.
Can someone briefly explain the difference between a Conceptual Class Diagram and a Detailed Class Diagram?
While a "Conceptual Class Diagram" expresses a conceptual (domain) model, it's not clear what you (or your professor) mean(s) with "Detailed Class Diagram": it could refer to a (language-/platform-independent) design model or to an implementation model like a C++ class model or a Java class model.
See also my answer to this related SO question.
The one-to-many relationships between conceptual models and design models, and between design models and implementation models are illustrated in the following Figure:
As an example that illustrates how the derivation chain from concept via design to implementation works, consider the following model of a people/Person concept/class:
Domain models are solution-independent descriptions of a problem domain produced in the analysis phase of a software engineering project. The term "conceptual model" is often used as a synonym of "domain model". A domain model may include both descriptions of the domain’s state structure (in conceptual information models) and descriptions of its processes (in conceptual process models). They are solution-independent, or ‘computation-independent’, in the sense that they are not concerned with making any system design choices or with other computational issues. Rather, they focus on the perspective and language of the subject matter experts for the domain under consideration.
In the design phase, first a platform-independent design model, as a general computational solution to the given software engineering problem, is developed on the basis of the domain model. The same domain model can potentially be used to produce a number of (even radically) different design models representing different design choices. Then, by taking into consideration a number of implementation issues ranging from architectural styles, nonfunctional quality criteria to be maximized (e.g., performance, adaptability) and target technology platforms, one or more platform-specific implementation models are derived from the design model.
A conceptual class diagram is used to understand and analyze a problem domain. A detailed class diagram is a design artifact, where many things may have been optimized away. For example, every dog might bark, but a dog-salon application doesn't care, so it can optimize away that fact.
I don't know of any standard or methodology that defines both these concepts. For example, the UML specification does not mention them. I think every answer will be subjective. I will give my own answer, based on more than 25 years of experience with IT-related modeling.
In a conceptual class diagram, every class is a concept, usually related to the business domain, the real world, e.g. Customer, Order etc. It may also show concepts that cannot be directly found in the business domain, but are needed to model the functionality of a particular application, e.g. BackupCopy. These are concepts the user of the application must understand. See also www.agilemodeling.com
There are other types of class diagram, e.g. class diagrams that model the source code, where every class corresponds to a Java class or a C# class, or class diagrams that model the physical database structure, where every class corresponds to a database table.
Each of these types of class diagrams may or may not be detailed. If a class diagram is not detailed, it typically does not show any attributes, or only the main attributes. If a class diagram is detailed, it shows all attributes relevant for the problem at hand and the data types of these attributes.
The concept of a conceptual class diagram is e.g. explained by Scott Ambler at http://www.agilemodeling.com/artifacts/classDiagram.htm#ConceptualClassDiagrams.
Basically "Conceptual" here means that the content of the diagram is taken from an analytic view point that takes the "concepts" of a domain and describes them.
For "concept" you could also say:
thing
item
aspect
object
topic
The conceptual diagram is basically what you get if you ask people for what problem they'd like to get solved by your software. So you analyze the situation/problem by asking questions that will help you create you diagram:
what are the things that are relevant? - these will be your candidates for classes
what are the features of those things? - these are the candidates for your attributes
how are the things releated to each other - e.g. is one part of another? Does it need the other? - these are the candidates for your relations
what should you be able to do with these things in your system ? - these are the candidates for your operations
In the past this step was called OOA - object oriented analysis. The steps following this are OOD - object oriented design and OOI - object oriented implementation. Many years ago some authors proposed to create three different models for OOA/OOD and OOI. Therefore you'd have different and usually more detailed diagrams for OOD and OOI. For the term "Detailed Class Diagram" i'd guess that one of the OOD and/or OOI views would be meant. Be careful though - some of the diagrams created this way will have patterns or pattern-like ideas as a basis. You'r diagrams would tend to be very repetitive and redundant if you keep capturing such patterns in concrete diagrams for every conceptual diagram. I'd rather recommend to give just one example of how to go from problem to solution and then comment "do it this way for all other concepts that are similar".
i'm php developer using MVC architecture that i'm new to UML
i know use-case , class , object , activity, sequence diagrams but i don't know for modeling a application where i should start.
i know use-case and class diagrams are structural diagrams and activity and sequence are behavior diagrams
but my questions are:
1. for modeling a app when i should use use-case diagram and when i should use class diagram?
2. does class diagram has abstract concept? because when i'm developing web app i have some controller and model or view also several classes that i use for different purpose (like insert data to database - validate form inputs and so on) but they don't look like to examples of class diagram that i'v seen until now so my question is class diagram is used for show concept of our system and it doesn't need to generate real class code form it ?
for example modeling a ticket reservation that may have some classes like this:
but we don't write class codes like this and it can be different in programming but for view the concept we are using class diagrams . is it true ?
Use-case diagram is usually used for representing the business of the project, indicate who(actor) are going to utilize the system and what services(cases) does program provide?
The class-diagram is used for specifying the whole system structure, but there no code and exact behavior will be provided by the class, generally developers don't specify the exact behavior with each module in-detail.
for example, consider a simple login module. in use-case diagram, we just mention that user logins into the system.
In class diagram we specify the possible base classes are needed, in other word we apply the architecture (we are planning) basis.
In sequence diagram we focus more on what is going on each method(while this is not necessary).
In fact UMl is used for representing the system as abstract, not the exact(in-detail) functionality.
for example I pass the above class-diagram to a developer, and tell him about the detail login process as a separated document.