Class Diagram - Low Level Design | Coding Interview Series | The Code Mate

Class Diagram :

While writing a Low-Level Design, Designing of Class Diagram is highly recommended as it gives many advantages. It is a UML diagram used to do forward or reverse engineering.

In this session, we will explore the basics of the Class Diagram, How different relationships of OOP can be represented in the class diagram.

The Session will give you a brief insight into various fundamentals of Class Diagrams, Through this session, you will learn the following topics:

1. Overview Of Class Diagram and Benefits of it.
2. Class representation on Class Diagram
3. Association and its representation on Class Diagram
4. Aggregation
5. Composition
6. Generalization
7. Dependency
8. Multiplicity
9. Abstract Class, Interface, and Enum representation.

#lld #llddesign #systemdesign #design #interviews #classdiagram

[shivaprasad]

Simple & Crisp explanation buddy, summed up at the end with very decent example, thanks a lot, Keep creating the content in similar way

[ArunKumar-wyqv]

Shouldn't the Order and OrderDetails be a composition relationship?

[littlemini]

why is the relationship b/w Order and OrderDetails an aggregation and not composition as when the order is destroyed order details will be destroyed too.

[abhishekkanchan]

In the Car - Engine composition example, should the relation be such that Car cannot exist without Engine i.e A can't exist without B?

[vlogazon]

Order detail can exist without order? Shouldn't that be composition?

[niksgupta]

At 6:24, Bi-directional, if city can call state, shouldn't City class should have getState() method?

[vikashkumarchaurasia]

Very nice video. It really helps me to understand all basics.🙏. Thanks a lot !!!

[nakulsuresh]

Hi, thank you for your explanation. What is the difference between unidirectional association and aggregation? Can they be used interchangeably?

[alfrieghtsnalam]

can you please add more topic for the system design begginers to advance

[akashjain]

Why OrderDetails is being modelled as a seperate entity, should'nt it be a value object with all its fields inlined as part of Order itself ?

[your_name]

Shouldn't the arrow be from Payment to Order, as Payment is dependent on Order entity ?

[sourabhshrivastava]

I think in Aggregation and composition we should say it is not an arrow, it is an diamond arrow

[t-distributedkid]

I think order and orderdetails should be in composition relationship rather than a aggregation since order details cannot exist without order and order details will change based on order.

Only if there is a thing as "empty order" can order details and order be in aggregation which is not thr case i guess..

Pls respond

[abhi]

Please share platform used for drawing class diagram

[prabhumk]

7:08 for unidirectional, banks have customers, but customer may have bank or may not have bank, I
'm confused

[akshaynanavare]

One doubt on last diagram
1. Why there is no composition between customer class and order class instead association. Because order can not exist without customer,
if order is created then it will be by customer only ?

[amarlearning]

I don't know why you are not passing the age param in the setAge method.

[vasudevjamwal]

I think the car and engine example is not a good one….there are so many examples to easily understand it, like hotel and room

[bhanu]

What's the difference between association and dependency??

[subbumotepalli]

Class diagram will write for entire project ?
Class diagram for every class need to draw?
Or class diagram write for module ?