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[CS Technical Interview 6] Java and Object-Oriented Programming Made Clear

Name: [CS Technical Interview 6] Java and Object-Oriented Programming Made Clear
Price: 38500 KRW
Rating: 4.9 (18 reviews)

A course that helps you understand core Java and Object-Oriented Programming (OOP) concepts, and includes practice explaining them verbally in interviews

(4.9) 18 reviews

394 learners

Level Basic

Course period Unlimited

yiyj10305235

3시간 만에 완강할 수 있는 강의 ⏰

자바

java

객체지향

비전공자

Java

oop

Tech Interview

3시간 만에 완강할 수 있는 강의 ⏰

자바

java

객체지향

비전공자

Java

oop

Tech Interview

Reviews from Early Learners

4.9

5.0

pray

100% enrolled

Wow... this is really so good...;;;; I need to save up money and buy everything in the roadmap.. I'm curious if you're planning to do any Spring lectures too.. I'll buy it right away..

5.0

karabiner

100% enrolled

The lecture pinpointed the key points, making it highly efficient for the time invested.

5.0

박상완 Sang Wan

55% enrolled

While preparing for Java developer interviews, I needed a systematically organized lecture, and this course was a great help. The detailed explanations of JVM structure, memory areas, exception handling, and other theories are memorable. This is a core summary lecture that can be directly applied in actual interviews.

What you will gain after the course

Understanding Core Object-Oriented Concepts in Java
The ability to explain things verbally in technical interviews
A practical workbook PDF that prepares you for follow-up questions

🥲 Have you ever had this experience in an interview?

1. Confusing concepts when answering

❓InterviewerWhat are the characteristics of object-oriented programming?
💬 Candidate The SOLID principles. First, S is..(omitted)...
This is a situation where the characteristics of object-oriented programming (abstraction, encapsulation, inheritance, polymorphism) and
object-oriented design principles (SOLID) are confused.
This can give the impression that the foundational framework of basic concepts is not established.

2. Knowing only What, but unable to explain How / Why

❓Interviewer What are the characteristics of TCP?
💬 Candidate It's a protocol that guarantees reliability.
❓ Interviewer What mechanisms guarantee reliability?
💬 Candidate Uh... well... it makes transmission safe... like...
You only know the superficial definition and are not prepared to explain the underlying principles.
If the 3-way handshake, sequence numbers, ACK, retransmission, flow control, and congestion control
are not connected as a single flow, you will inevitably get stuck on follow-up questions.

3. Getting stuck on basic questions

❓Interviewer What is HTTP?
💬 Candidate Um... it's for sending and receiving data on the web... something like that...?
It's a concept you're very familiar with, but when you actually try to explain it in one sentence, the words don't come out.
This isn't a lack of knowledge, but rather a lack of experience organizing and articulating it.

Just knowing is not enough. It only becomes true skill when you can articulate it.

1⃣ CS Notes organized specifically for interview preparation

All essential concepts and principles you must review before interviews are compiled and provided as lecture materials.
While building your fundamentals, it's structured so you can review it again right before your interview.
Not just a simple summary, but with diagrams and easy explanations that even non-majors can fully understand.

Computer Architecture Lecture Material Example

2⃣ Appendix | Interview Practice Materials Provided

In interviews, the ability to explain clearly is far more important than simply knowing something.
However, organizing and practicing on your own is not easy and can be tedious.
At the end of the lecture materials, we've included "answering in one or two sentences" training to reduce the effort of organizing.

Database Course Appendix Example

3⃣ Prepare for follow-up questions with our Technical Interview Practice Workbook PDFincluded

"Will this course alone really be enough for speaking practice?"
After pondering this question,
I created a Technical Interview Practice Workbook.
I designed it so you can practice speaking as if in a real interview even on your own.
You can find detailed information about the workbook structure and how to use it in the workbook introduction video at the beginning of the course.

Operating System Workbook Example

4⃣ A course that keeps growing with a one-time purchase

This course is provided with unlimited access period.
The content will continue to expand with new explanations, additional examples, and more.
Even if the price increases as content is added, students who have already purchased
can access all content at no additional cost.
It's a CS fundamentals book you can keep coming back to whenever you need it.

1⃣ Download the materials and learn key concepts while watching the lectures.
2⃣ Take notes on important parts to create your own CS interview notebook.
3⃣ Save it on your phone and review briefly whenever you have time.

If you have an interview coming up,
and don't have much time → Use the appendix [Interview Practice] in the course materials to quickly sharpen your interview skills.
If you have time → Complete your speaking practice like a real interview with the Technical Interview Practice Workbook..

⭐️⭐️⭐️⭐️⭐️

1. A lecture that shows how much the author has thought and considered from the student's perspective (seems to consider the learner's flow of understanding)
2. Easy to understand with diverse visual materials and examples
3. When learning knowledge, it mentions and reminds you of previously learned content, connecting the knowledge. Knowledge connects and the big picture emerges.
4. The depth of knowledge is not shallow. I'm taking OS right after Computer Architecture, and the synergy is great.
5. Scratches all the itches about "why" & "why it's used".
ps. Sorry to the author, but.. this is a lecture I want to keep to myself.

-'Operating Systems' Course Review

⭐️⭐️⭐️⭐️⭐️

Despite the short lecture duration, I really appreciate how you clearly explain only the important parts. Since it was somewhat theory-focused, I didn't expect SQL queries to be covered, but it was great that you showed examples one by one while teaching basic syntax and how to write queries. After that, the coverage of joins, normalization, transactions, indexes and data optimization, and security was excellent. I haven't tried other paid courses yet, but the last lecture appendix titled "Interview Practice" was great for self-study and practice as it directly showed questions and answers. The lecture duration isn't too long if you focus, so I think I'll go through it multiple times. Thank you

-'Database' Course Review

🖐 Hello! Let me introduce myself! 🙇

As a non-CS major, when I first prepared for a developer job, I only focused on algorithms and coding tests.
I gained some confidence and passed most coding tests, but I kept failing at the next hurdle—technical interviews. What was the problem? It was the lack of CS (Computer Science) knowledge.

I understand the thirst for fundamentals (CS knowledge, programming languages, etc.) better than anyone. I dove into countless materials through self-study and built my own know-how, and now I'm working as a 🧑🏻‍💻 Kakao developer.

Since I was young, I've been more confident than anyone in combining and reorganizing various materials to create 'my own consolidated notes'. This course is the secret notebook that contains all that know-how and passion.

Object-Oriented Basics
- Features of Object-Oriented Programming, SOLID Principles, etc.
Java Overview
- Java features, JVM / Garbage Collector (GC), reference types, Call by Value, static keyword, etc.
Object-Oriented Programming
- Java's OOP, polymorphism, interfaces and abstract classes, etc.
Collections
- Characteristics of List, Set, Map and various comparisons
- Comparison of various Sets (HashSet, LinkedHashSet, TreeSet)
- Comparison of various Maps (HashMap, LinkedHashMap, TreeMap, ConcurrentHashMap)
Multithreading and Concurrency
- Multi-threading implementation methods
- • synchronized keyword and volatile keyword, etc.
Exception Handling and Other Concepts
- Exception handling methods, exception hierarchy, serialization/deserialization, String vs StringBuilder/StringBuffer comparison, etc.
Modern Java (Java 8 and later)
- Functional interfaces and lambda expressions, comparison of collections and streams
[Appendix] Interview Practice
- Review key concepts once more in Q&A format

2⃣ Easily explain confusing core Java concepts with diagram-focused illustrations

JVM and Memory Structure The JVM execution process and the roles of Stack/Heap memory areas are easily explained through diagrams.
GC (Garbage Collector) Operating Principles Learn the complex GC process not through abstract explanations but by following visual diagrams, allowing you to firmly grasp the concepts.
You will learn in depth how the call by value method is reflected in actual memory state and code execution, along with diagrams. được phản ánh trong trạng thái bộ nhớ thực tế và việc thực thi mã thông qua sơ đồ minh họa.

Recommended for
these people

Who is this course right for?

A non-CS major who feels lost because they're new to studying computer science
A computer science major who needs to organize CS concepts before a technical interview
A job seeker preparing for a career change who has limited time before a technical interview

Need to know before starting?

JAVA Basic Syntax
Learning becomes much easier if you have basic operating system concepts like memory and threads.

Hello
This is

3,673

Learners

164

Reviews

Answers

4.9

Rating

Courses

학력 및 경력

서울대학교 졸업
현 카카오 서버 개발자

강의 소개

CS 개념을 면접에서 말로 풀어낼 수 있도록 돕는
말이 트이는 CS 시리즈를 만들고 있습니다.

강의 철학

컴퓨터 비전공자로 개발을 시작해 CS 기초부터 기술 면접까지 직접 정리하며 시행착오를 많이 겪었습니다. 그 과정에서 쌓인 학습법과 개념 정리 노하우를 바탕으로, 실무와 면접에서 꼭 마주치는 핵심 개념을 그림으로 쉽게 이해할 수 있도록 만드는 콘텐츠를 제작하고 있습니다.
"그때의 저에게 필요했던 강의를 만들고 있습니다."

블로그

yiyj1030.tistory.com
→ CS, 알고리즘, 실무 개념을 쉽고 정리하는 기술 블로그 운영 중

Contact

yiyj1030@gmail.com

Curriculum

All

33 lectures ∙ (3hr 6min)

Course Materials:

Lecture resources

Section 1. INTRO: Course Introduction and Overview of Contents

4 lectures ∙ (10min)

Section 2. Object-Oriented Design Principles and Patterns

2 lectures ∙ (26min)

Section 3. Java Core Structure and Memory Mechanism

7 lectures ∙ (51min)

Section 4. Java and Advanced Object-Oriented Programming (OOP)

4 lectures ∙ (18min)

Section 5. Complete Mastery of the Collection Framework

3 lectures ∙ (13min)

Section 6. Multithreading and Concurrent Programming

3 lectures ∙ (26min)

Section 7. Exception Handling and Advanced Java Techniques

7 lectures ∙ (19min)

Section 8. Modern Java: Java 8+ Features and Applications

2 lectures ∙ (9min)

Section 9. Appendix [Interview Practice]

1 lectures ∙ (10min)

Published:

Last updated:

Reviews

All

18 reviews

4.9

18 reviews

tommy0419
Reviews 24
∙
Average Rating 5.0
5
100% enrolled
I took this course to quickly review concepts. Overall, you covered everything well, which helped me review quickly. Thank you.
asd21123
Reviews 11
∙
Average Rating 4.5
5
100% enrolled
Wow... this is really so good...;;;; I need to save up money and buy everything in the roadmap.. I'm curious if you're planning to do any Spring lectures too.. I'll buy it right away..
happhuy2089
Reviews 1
∙
Average Rating 5.0
5
100% enrolled
It felt like it meticulously filled in the missing parts. I think other series would also be helpful to watch before interviews.
- yiyj10305235
  Instructor
  Thank you for the course review. I hope this lecture isn't the end and that we can continue the learning journey together. I look forward to seeing you again in the next series :)
doitdoit
Reviews 28
∙
Average Rating 5.0
5
100% enrolled
This is a lecture you can watch to grasp the major topics before an interview.
- yiyj10305235
  Instructor
  Thank you for the course review. I hope this lecture isn't the end and that we can continue the learning journey together. I look forward to seeing you again in the next series :)
javarunner
Reviews 76
∙
Average Rating 4.9
5
31% enrolled
- yiyj10305235
  Instructor
  Thank you for the course review. I hope this lecture isn't the end and that we can continue the learning journey together. I look forward to seeing you again in the next series :)

$29.70

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[CS Technical Interview 6] Java and Object-Oriented Programming Made Clear

Reviews from Early Learners

4.9

What you will gain after the course

🥲 Have you ever had this experience in an interview?

2. Knowing only What, but unable to explain How / Why

3. Getting stuck on basic questions

Just knowing is not enough. It only becomes true skill when you can articulate it.

🔥 So we've structured it this way.

✦ A cut above the rest, premium content for interview preparation

💡 Here's how to make the most of this abundant content

🎯 Recommended for

🔥 Reviews from students who experienced it first

🖐 Hello! Let me introduce myself! 🙇

🚀 The sixth course in the CS Series That Opens Your Mouth is Java & OOP.

📖 A curriculum packed with only the essentials chỉ chứa những nội dung cốt lõi

✏ What You'll Learn

1⃣ Object-Oriented Design Principles and Application Methods

2⃣ Easily explain confusing core Java concepts with diagram-focused illustrations

3⃣Multithreading and Synchronization Strategies for Immediate Practical Use

👀 Course Preview

🔗 Go to the CS Series That Makes Sense

Things to Note Before Enrolling

Recommended for
these people

Hello
This is

Curriculum

Reviews

yiyj10305235's other courses

Similar courses

[CS Technical Interview 6] Java and Object-Oriented Programming Made Clear

Reviews from Early Learners

4.9

What you will gain after the course

🥲 Have you ever had this experience in an interview?

2. Knowing only What, but unable to explain How / Why

3. Getting stuck on basic questions

Just knowing is not enough. It only becomes true skill when you can articulate it.

🔥 So we've structured it this way.

✦ A cut above the rest, premium content for interview preparation

💡 Here's how to make the most of this abundant content

🎯 Recommended for

🔥 Reviews from students who experienced it first

🖐 Hello! Let me introduce myself! 🙇

🚀 The sixth course in the CS Series That Opens Your Mouth is Java & OOP.

📖 A curriculum packed with only the essentials chỉ chứa những nội dung cốt lõi

✏ What You'll Learn

1⃣ Object-Oriented Design Principles and Application Methods

2⃣ Easily explain confusing core Java concepts with diagram-focused illustrations

3⃣Multithreading and Synchronization Strategies for Immediate Practical Use

👀 Course Preview

🔗 Go to the CS Series That Makes Sense

Things to Note Before Enrolling

Recommended for these people

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

Curriculum

Reviews

yiyj10305235's other courses

Similar courses

Recommended for
these people

Hello
This is