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CS Interview Preparation Guide: Java Edition – Directly from Channel Talk Interviewers

Channel Talk interviewers will directly analyze the difference between failing and passing answers to the same question and help you prepare for actual follow-up questions.

(5.0) 35 reviews

370 learners

Level Basic

Course period Unlimited

Java
Java
oop
oop
computer-science
computer-science
Java
Java
oop
oop
computer-science
computer-science

Reviews from Early Learners

5.0

5.0

smathj

100% enrolled

I enjoyed watching this. I've gained diverse perspectives and learned about keywords I should continue to study. Thank you.

5.0

황규운

13% enrolled

It feels so good to practice putting concepts that only existed in my head into words. In particular, it is very helpful when you point out the specific keywords that must be included.

5.0

Bruce Han

100% enrolled

It was a high-quality interview preparation lecture that covered both Java and CS at once. It feels so refreshing. Thank you. I will get a lot of help from this and pass the interview.

What you will gain after the course

  • A perfect model answer evaluated by the interviewer

  • The critical difference between a failing answer and a passing answer to the same question

  • Full set of actual interview questions and follow-up question pedigrees from Naver, Kakao, LINE, Coupang, Baemin, Danggeun, Toss, and Unicorn companies (100+ items)

  • Answering skills that make you say "I nailed the interview" instead of "I blew the interview"

🤬 Java interviews—I clearly know all the content, so why can't I get the words out?!

I'm Jayon, currently working as a backend engineer and interviewer at Channel Talk after completing the Woowa Course and working as a backend engineer at several companies. I wasn't someone who was good at interviews from the start either. In fact, I ranked near the bottom in the Woowa Course mock interviews, to the point where I even had to have a separate meeting with the CEO.


GC principles? I knew them. JVM structure? Of course I had it organized. But everything changed once I sat down in the interview room.

"Please explain the pros and cons of the JVM." Up to that point, it was fine. I spoke smoothly, just as I had prepared. But the moment the interviewer picked out one of my answers and asked, "Then why is the performance slow?" my mind went completely blank. I knew I had seen it somewhere. I had even organized my notes on it. But in that moment, I just didn't know what to say.

When I searched for it on my phone after the interview and realized, "Ah, it was this...", that feeling of emptiness... I'm sure many people can relate.


From then on, I started recording and reviewing my interviews. I created a "wrong answer note" and compared my previous answers with my current ones for the same questions. As I accumulated over hundreds of questions and answers, patterns began to emerge. I started to see which answers convinced the interviewers and which ones invited unnecessary follow-up questions.


It was only after going through this trial and error hundreds of times that I realized: knowing the theory and speaking in an interview are two completely different skills. That's why I decided I had to create a course focused solely on "how to answer the questions."

✨ 4 Key Points I focused on while creating this course

This is not a theoretical summary lecture. Lectures that summarize "What is JVM" are already abundant on blogs. This lecture teaches you, "If the interviewer asks this, answer like this." Each lecture corresponds to a single interview question, breaking down step-by-step how you should respond to that question.

We provide a comparative analysis of three levels of answers—Bronze, Silver, and Gold—for the same question.Bronze is a 50-point answer out of 100, Silver is an 80-point answer, and Gold is a 100-point answer. We show you specifically why the outcome can differ between passing and failing even when using the same keywords.

The content is based on actual interview questions from major corporations and unicorn startups. It includes not only the main questions but also the follow-up questions that actually follow. From the main question to the follow-up and the follow-up to that, the lectures are structured exactly how the flow of questions happens in a real interview.

Frequently asked questions are provided as an appendix PDF and are continuously updated.Frequently asked questions not covered in the lecture are provided in a separate PDF, and we plan to keep adding more in the future. Once you make a purchase, you can continue to receive all updated appendices.

👍 This is recommended for the following people!

Those who can answer the initial question but find their mind going blank when follow-up questions start coming.

Those who want to know the interviewer's inner thoughts, like "What would they think if they heard this answer?"

Those who want to get hired by IT service companies like Kakao, Naver, LINE, and Toss.

🍡 Preview

'Please explain the algorithms used in GC. Which algorithm does Java use?' during class

'Please explain Java's concurrency issues.' During class

'(Follow-up question) What exactly is functional programming?' During class

✔ Notes

  1. Java basic theory is assumed to be known before proceeding with the class. You should have been exposed to concepts such as JVM and GC at least once to maximize the effectiveness of the lecture.

  2. If you happen to come across any parts you don't understand while studying, please feel free to ask questions immediately by using the Q&A board😊


🚨 Be sure to check who the person providing the education is!

If you meet the wrong doctor, you may face death because your illness cannot be cured at that moment. However, death ends with the pain of that moment. But if you meet the wrong teacher and receive a poor education, you will suffer throughout your entire life.

Due to poor education, you may end up at a company you don't want to work for, receive a lower salary than expected, and suffer for the rest of your life as a result. Not only that, but the poor education you received can be passed down to your children as a cycle of misguided learning.

I believe that education can change a person's life very positively, but on the other hand, it can also completely ruin a person's life. That is why I believe education carries such a heavy responsibility.

Therefore, please check who the educator is, what kind of person they are, and what path they have taken, and make a careful decision.

👋 Hello!
I'm finally introducing myself ( ⸝⸝•ᴗ•⸝⸝ )੭⁾⁾

Hello!

I am Jayon, a 5th-year developer working as a backend engineer at Channel Corp.

I completed the Woowa Tech Course 3rd Backend program and started my career at a small SI company. My salary was at the minimum level. To escape that situation, I spent a tremendous amount of time preparing for coding tests and interviews. As a result, after passing through Chai Corporation (PortOne), I am currently earning several times my initial salary while managing Channel Talk's core systems, which handle billions of records.

I realized through this process that it is truly difficult to find the right direction when preparing for a job alone. That is why I have been active as a backend mentor at F-Lab, JSCODE, and Fast Campus, and also served as a reviewer for the 5th Woowa Tech Course. Through mentoring, I have helped students successfully land jobs at top-tier tech companies (Naver, Kakao, Line, Coupang, Baemin, Danggeun, Toss), unicorn startups, and major corporations, and the know-how accumulated during that process is fully captured in this course.

Just as I received a lot of help when I was going through difficult and challenging times, I wanted to become someone who could also help many others. I felt the most proud and happy when the value I created through development had a positive impact on other people.

I also run a technical blog, steady-coding, so if you're curious about what kind of developer I am, please feel free to visit!

Thank you! 🚌 Feeling lost on which CS interview prep lecture to start with?


🐶 Get a discount on lectures with the roadmap

➡ CS interview preparation directly from a Channel Talk interviewer

(https://inf.run/8VEbS)

Recommended for
these people

Who is this course right for?

  • Those who want to get hired by IT service companies like Kakao, Naver, LINE, and Toss.

  • Those who want to cram for a Java interview in 3 hours right before the meeting.

  • Those who are curious about frequently asked interview questions and the scoring criteria.

  • Those who want to know the inner thoughts of interviewers, wondering, "What will they think when they hear this answer?"

  • Those who have never done a CS interview before and don't even have a sense of what kind of questions will be asked.

  • Those who can answer the initial question but find their mind going blank when follow-up questions are asked.

Hello
This is jayon0927

Inflearn Verified

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Answers

5.0

Rating

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[Contact]

Go to LinkedIn

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[Career]

Current) Channel Corp - Lv 4. Backend Engineer

Former) Chai Corporation (PortOne) - Backend Engineer

 

[Education]

Current) F-Lab Backend Mentor

Current) JSCODE Backend Mentor

Former) Woowa Tech Course 5th Gen Backend Reviewer & 3rd Gen Backend Graduate

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Curriculum

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47 lectures ∙ (2hr 56min)

Course Materials:

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Reviews

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35 reviews

5.0

35 reviews

  • hgkimer님의 프로필 이미지
    hgkimer

    Reviews 4

    ∙

    Average Rating 4.8

    5

    100% enrolled

    I really like the way it expands based on the level of the answer and how it follows up with tail questions to verify! The lecture on the AI era at the end was also particularly informative.

    • jayon0927
      Instructor

      Hello, HOGYU KIM! Thank you for leaving such a great review😊 I will continue to repay your support with even better lectures in the future!

  • 01064826876a3667님의 프로필 이미지
    01064826876a3667

    Reviews 1

    ∙

    Average Rating 5.0

    Edited

    5

    13% enrolled

    It feels so good to practice putting concepts that only existed in my head into words. In particular, it is very helpful when you point out the specific keywords that must be included.

    • jayon0927
      Instructor

      Hello, Gyu-un Hwang! Thank you for leaving such a great review😊 I will repay your support with even better lectures in the future!

  • dbpjack님의 프로필 이미지
    dbpjack

    Reviews 10

    ∙

    Average Rating 4.5

    5

    32% enrolled

    These answers get straight to the point. Studying by looking at the Q&A and then searching for additional information really helps me learn well.

    • jayon0927
      Instructor

      Hello, Homebody-JPA, Ko/Jup, AWS, Woo! Thank you for leaving such a great review😊 I will continue to repay you with even better lectures in the future!

  • brucehan님의 프로필 이미지
    brucehan

    Reviews 95

    ∙

    Average Rating 4.5

    Edited

    5

    100% enrolled

    It was a high-quality interview preparation lecture that covered both Java and CS at once. It feels so refreshing. Thank you. I will get a lot of help from this and pass the interview.

    • jayon0927
      Instructor

      Hello, Bruce Han! Thank you for leaving such a great review after completing the course😊 I'll be rooting for you to get into your target company~!!

  • smathj9975님의 프로필 이미지
    smathj9975

    Reviews 61

    ∙

    Average Rating 5.0

    5

    100% enrolled

    I enjoyed watching this. I've gained diverse perspectives and learned about keywords I should continue to study. Thank you.

    • jayon0927
      Instructor

      Hello, smathj! Thank you for leaving such a great review😊 I will continue to strive to provide even better lectures in the future!

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