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Object - Design Principles

Name: Object - Design Principles
Price: 82500 KRW
Rating: 5 (45 reviews)

Learn various design principles needed to write object-oriented code, focusing on working code.

(5.0) 45 reviews

809 learners

Level Basic

Course period Unlimited

eternity

oop

Software Test

software-design

oop

Software Test

software-design

Reviews from Early Learners

5.0

최은혁

30% enrolled

This lecture broke down core refactoring principles through practical examples that could be immediately applied to real work. The process of simplifying long methods into composed methods, revealing hidden concepts with value objects, and separating classes using the single responsibility principle was very clear. I could feel the effects of increased cohesion and readability, while reducing unnecessary coupling and duplication. It was a beneficial lecture that made complex design principles easy to understand and immediately applicable for improving team code quality.

5.0

신제우

15% enrolled

I can confidently say that Youngho's Object lecture is something I would recommend listening to regardless of what language you use. You'll be incredibly happy while listening to very well-organized design theory through Youngho's detailed, meticulous explanations that become more delicious the more you savor them. For a while, I was fortunate enough to have Youngho visit the events I participated in, where he shared many wonderful stories with us. Since I started developing, those moments when I could listen to Youngho's stories were truly the 'happiest moments' for me. I want to express my gratitude for creating such valuable experiences. While waiting for the next lecture to come out, I'll be savoring the realizations as I try out the things Youngho taught us :)

5.0

크리스팍

100% enrolled

This is a premium lecture on the core principles and fundamentals of object-oriented development~ I can say there's a world of difference between developing with knowledge of these principles versus developing without them. If you're currently developing without knowing these principles, you'll eventually realize that you've been writing spaghetti code~!! :) Let's all keep fighting today to create code that's easy to maintain~ 😊

What you will gain after the course

Object-Oriented Design Principles
Identifying code problems using design principles
How to evolve code through refactoring
Relationship between Tests and Code Quality

Object-oriented design principles,
Understand how to apply 🤔

While writing Object , there were many topics that I could not include or explain sufficiently due to space constraints, and the most regrettable of these was that I could not systematically organize the contents of design principles. Although I briefly mentioned some design principles or explained the background and necessity of the principles from the perspective of cohesion, coupling, and encapsulation, I could not include a method of connecting various principles in the context of design and a specific guide for applying these principles.

To complement this, the Object - Design Principles section focuses purely on design principles, explaining practical methods for applying design principles when evaluating and improving code at the specific code level. Through the lecture, you will learn how to identify and improve problems in code based on design principles. As a result, after listening to the lecture, you will understand how to design easy-to-maintain code by combining various design principles.

The design principles covered in the lecture are:

Single Level of Abstraction Principle ( SLAP )
Single Responsibility Principle ( SRP )
Open-Closed Principle ( OCP )
Liskov Substitution Principle ( LSP )
Dependency Inversion Principle ( DIP )
Interface Segregation Principle ( ISP )
Law of Demeter ( LoD )
Tell, Do n't Ask ( TDA )
Command Query Seperation ( CQS )
Do n't Repeat Yourself ( DRY )

Concept and necessity of design principles

All design principles share the goal of improving the quality of the design. However, the specific goals of each design principle are different. Therefore, the starting point for understanding design principles is to understand the goal that each design principle is trying to improve, and to determine whether improving the current code to meet that goal is appropriate.

By taking the lectures, you will naturally understand why each design principle is necessary and when it is useful.

How to apply design principles comprehensively

Design principles are not used in isolation. When writing code, it is common to apply a variety of design principles in combination. And in order to follow one design principle, other design principles must also be considered. Considering design principles in combination enhances the ability to make design tradeoffs in various situations.

In this course, you will learn how to use a variety of design principles in combination while showing how code can be improved through successive refactorings.

Object - Relationship with the basics

You do not need to have taken Object - Basics to listen to Object - Design Principles. While Object Basics covers a top-down approach to creating maintainable designs using Responsibility-Driven Design, Object Design Principles covers a bottom-up approach to refactoring code to make it maintainable.

The two lectures are complementary rather than interdependent, as they cover object-oriented design from different perspectives. Therefore, you can take the lectures in any order, and after taking both lectures, you will gain a comprehensive view of object-oriented design.

It's special in this respect

📌 Describes language-independent object-oriented design principles.

📌 Although the examples are implemented in Java, the concepts presented in the lecture are applicable to any language or environment.

📌 We provide 1400 pages of slides filled with key content.

📌 We have organized the content so that it is easy to understand by expressing the concepts in visual pictures rather than simple text.

📌 Since the refactoring process is conveyed using pictures, it is easy to understand the code change process.

Player Knowledge and Notes

Since the example code is written in Java, you need to know basic Java grammar to learn smoothly.
I wrote the lecture using only the most basic JDK, but some examples use JSON parsing.
Jackson library , embedded-redis library for in-memory Redis support
, Redis Java Client Jedis Library
, which includes a section using the Swing framework for developing GUI applications.
Even if you don't know these libraries, we've structured it so that you can learn the core principles without difficulty.
We use Junit and AssertJ as unit testing libraries.

Recommended for
these people

Who is this course right for?

Those curious about the concepts and application methods of Object-Oriented Design Principles
Those who find it difficult to apply object-oriented concepts in code
For those who need basic principles and guides for designing good code

Need to know before starting?

Java basic syntax
Experience writing code using object-oriented languages

Hello
This is

2,542

Learners

173

Reviews

101

Answers

5.0

Rating

Courses

I am an ordinary developer with a deep interest in object-oriented design and domain-driven design, holding the belief that happy teams, clean code, respect, and collaboration lead to great software. Based on my diverse experiences moving between roles as a developer, educator, and manager, I strive to create great products alongside good code.

His authored books include The Essence of Object-Orientation and Objects, and his translated works include Elegant Objects, and he participated as a technical reviewer for Get Your Hands Dirty on Clean Architecture.

💡Apply for Mentoring : https://inf.run/YvAd2

💡Personal Blog : https://eternity-object.tistory.com/

and participated as a technical reviewer for the book "Get Your Hands Dirty on Clean Architecture." 💡Apply for Mentoring: https://inf.run/YvAd2 💡Personal Blog: https://eternity-object.tistory.com/

Curriculum

All

33 lectures ∙ (6hr 16min)

Course Materials:

Lecture resources

Section 1. Course Introduction

2 lectures ∙ (13min)

Section 2. Text adventure game

2 lectures ∙ (23min)

3. 2-1. Text Adventure Game
10:56
4. 2-2. Testing and Refactoring
12:11

Section 3. Combining Methods

2 lectures ∙ (23min)

Section 4. Value Object and Reference Object

3 lectures ∙ (28min)

Section 5. Class Splitting

5 lectures ∙ (57min)

Section 6. Interface refinement

2 lectures ∙ (31min)

Section 7. Test and Dependency

5 lectures ∙ (53min)

Section 8. Adding a new feature

6 lectures ∙ (1hr 22min)

Section 9. Expanding Design

6 lectures ∙ (1hr 2min)

Published:

Last updated:

Reviews

All

45 reviews

5.0

45 reviews

haedallog
Reviews 16
∙
Average Rating 4.9
5
100% enrolled
It's an honor to leave the first review. After completing `<Object - Basics>`, I immediately took `<Object - Design Principles>` as well and am now writing this review. The advantages of the course are as follows: 1. It's easy to understand intuitively because it's not just listing principles but includes actual code examples. ㄴ I thought I knew the SOLID principles because I encounter them often, but after watching the lecture, I realized that was my misconception. 2. Convenience has increased compared to `<Object - Basics>`. ㄴ A link to the relevant repo is provided through the course materials, making it easy to access. ㄴ The presenter is no longer visible, making the presentation much easier to see. There are also some slightly disappointing aspects (They are minor). 1. The volume level differs slightly for each video, which is a bit distracting. 2. There are also cases where there are errors in the videos. 3. If colloquial phrases like '되게 됩니다.' were refined, it would feel tidier. 4. There are instances where the notation for foreign words differs (e.g., 메서드/메소드), and it would be a bit tidier if this were unified. I highly recommend watching `<Object - Basics>` as well. It allows for a broader understanding of the course. If you don't know what object-oriented design is, I strongly recommend this course. I plan to recommend it to many people around me as well 😊😊 Thank you to Jo Young-ho for planning this great course. I expect my code to change significantly in the future. Work less, earn more 😊😊😊
- eternity
  Instructor
  I remember you recently left a review for "Object - Basic Course", and you've already completed it. Congratulations on completing the course, and thank you for leaving a review. :) I'm glad the course was helpful. I decided to remove my face from the videos at the request of many acquaintances, and I'm glad the reaction has been positive... Due to health reasons, the filming period was extended, which resulted in slightly varying audio levels. If anyone finds this inconvenient, I will consider re-recording "Object - Basic Course" along with it in the future. :) I'm creating, filming, and editing the course by myself, and this course ended up having more presentation slides than expected. Although I checked in between, it seems there were parts I didn't notice. I apologize for releasing it without thoroughly checking this part. I will also review it again and make corrections as quickly as possible. :) If it's convenient for you, please let me know about any errors in the video or inconsistencies in the slides, and I will correct and update them as quickly as possible. The phrase "Work less, earn more" resonates with me. I hope the course helps reduce maintenance costs and improve code quality. Thank you!
개발인생
Reviews 2
∙
Average Rating 5.0
5
100% enrolled
I really enjoyed the lecture. I thought I knew the design principles well, but unexpectedly, there were many things I had misunderstood. Explaining using code made it easy to understand. I was unsure how to refactor code, but after the lecture, I was able to establish some clear criteria. Thank you for creating a great lecture!
- eternity
  Instructor
  Thank you for leaving a review, GaeBalInSaeng-nim. I'm glad the design principles, organized to be applicable when writing actual code, were helpful. :) If you have any questions, feel free to leave them anytime! Congratulations on completing the course, and have a happy start to your week.
enciel02028311
Reviews 3
∙
Average Rating 5.0
5
30% enrolled
It's exciting like watching a movie, as the story about design continues~ I'll keep listening carefully~ Thank you for the good lecture!
- eternity
  Instructor
  Thank you for leaving a review, Byung-mo Kim. It's structured to show how design principles are applied while improving examples, and it seems you're enjoying it. :) The difficulty increases slightly as you go towards the latter part, but more interesting content awaits, so please make sure to complete the course. If you have any questions or parts that need correction, please feel free to ask anytime. Have a great Friday night and spend happy days.
soljie742878
Reviews 2
∙
Average Rating 5.0
Edited
5
100% enrolled
Following the basic course, this seems like the best lecture on object-oriented programming. It is very substantial as it is composed of well-structured content from concepts to examples.
- eternity
  Instructor
  Thank you for leaving a course review, soljie74. If 'Object - Basic' explained how to write object-oriented code, 'Object - Design Principles' aimed to explain how to improve design using object-oriented principles, and I'm glad it was helpful. If you have any questions or suggestions for improvement, please feel free to ask anytime. Congratulations on completing the course, and have a good rest of your weekend!
chrispark
Reviews 7
∙
Average Rating 5.0
5
100% enrolled
This is a premium lecture on the core principles and fundamentals of object-oriented development~ I can say there's a world of difference between developing with knowledge of these principles versus developing without them. If you're currently developing without knowing these principles, you'll eventually realize that you've been writing spaghetti code~!! :) Let's all keep fighting today to create code that's easy to maintain~ 😊
- eternity
  Instructor
  Thank you so much for leaving a review, Chris Park. As you mentioned, I hope many people will be able to write clean code based on design principles. I'm so grateful that you're satisfied with the course, and I'll work hard to prepare the next course as well! Have a happy weekend. :)

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Object - Design Principles

Reviews from Early Learners

5.0

What you will gain after the course

Object-oriented design principles,
Understand how to apply 🤔

Learn about these things

Object - Relationship with the basics

It's special in this respect

Things to note before taking the class

Learning Materials

Player Knowledge and Notes

Recommended for
these people

Hello
This is

Curriculum

Reviews

eternity's other courses

Similar courses

Object - Design Principles

Reviews from Early Learners

5.0

What you will gain after the course

Object-oriented design principles, Understand how to apply 🤔

Learn about these things

Object - Relationship with the basics

It's special in this respect

Things to note before taking the class

Learning Materials

Player Knowledge and Notes

Recommended for these people

HelloThis is .css-1q3zd4q{text-decoration-line:underline;text-underline-position:under;text-underline-offset:1px;}

Curriculum

Reviews

eternity's other courses

Similar courses

Object-oriented design principles,
Understand how to apply 🤔

Recommended for
these people

Hello
This is