The Java, Java 8

Learn how to easily understand the principles and various functions of Spring Boot through coding and use them more actively.

Refactoring is one of the basic skills that a software engineer should have. This course is designed to explain and practice various code smells and refactoring techniques in a more practical way using IntelliJ and Java.

Understand the operating principles and structure of Spring Security and learn how to set up authentication and authorization features required for web applications by utilizing the various functions provided by Spring Security.

This course develops a REST API that satisfies Self-Descriptive Message and HATEOAS (Hypermedia as the engine of application state) using various Spring technologies.

Learn “Effective Java,” the ultimate Java learning guide, more easily and completely. By taking this course, you can improve not only your Java programming knowledge and skills, but also your learning ability.

Knowing design patterns will make it easier to learn not only Spring but also many other technologies and programming languages. It will also help you develop more flexible and reusable object-oriented software.

Learn “Effective Java,” the ultimate Java learning course, more easily and completely. By taking this course, you can improve not only your Java programming knowledge and skills, but also your learning ability.

If you want to grow as a developer who is recognized by your colleagues, team, and even the company, and can work with more responsibility and influence? In this lecture, I will share with you my know-how on growth.

Learn “Effective Java,” the ultimate Java learning course, more easily and completely. By taking this course, you can improve not only your Java programming knowledge and skills, but also your learning ability.

Developer interview taught directly by a senior software engineer who went through Naver and Amazon and is currently at Microsoft!! This lecture focuses on the "developer interview" rather than the "coding interview". When hiring a developer or, conversely, when changing jobs or seeking employment, the "coding interview" is never the only thing that determines success or failure. Through this lecture, I hope you will learn more about how to hire a developer or prepare for a change or seeking employment.

This lecture is an extension of the "Spring Boot Concepts and Utilization" lecture and covers the Spring Boot updates that have been made over the past two years. Check out the new features and changes from Spring Boot 2.1 to 2.4 and update to the latest version of Spring Boot.

In this course, you will learn how to develop a web application using various Java-based open source technologies including Spring, JPA, and Thymeleaf, which are actually operating services. If you study this course enough, you will be able to create your own web service or create a portfolio that will help you get a job.

If you are a student or developer who is using or studying the Java programming language, you will learn various methods of testing your applications that you must know.

Have you ever wondered "how" the many Java libraries and frameworks you use provide this functionality? In this course, learn how to manipulate various codes or objects provided by Java and take your Java skills to the next level.

This course is for those who are new to the Spring framework. By looking at the code of the official Spring example project called Spring - PetClinic, you can easily and quickly understand the following core features of Spring.

This course covers Spring Web MVC, a Java Servlet-based MVC framework. For a more efficient learning experience, please take the Spring Framework Core Technologies course.

By looking at the code of the official Spring example project called Spring-PetClinic, you can easily and quickly understand the following core features of Spring.

This course uses Spring Boot and teaches you the core Spring technologies. Therefore, this is a useful Spring course for developers or students who are using Spring Boot-based projects.

Learn about Spring Data JPA, which provides several features to make using JPA (Java Persistence API) easier.

Have you ever wondered "how" the many Java libraries and frameworks you use provide this functionality? In this course, learn how to manipulate various codes or objects provided by Java and take your Java skills to the next level.

If you are a student or developer who is using or studying the Java programming language, you will learn various methods of testing your applications that you must know.

You will learn Java's concurrency mechanisms and multithreading techniques in depth and acquire the knowledge and skills necessary to solve various parallel processing problems that you may encounter in practice. Starting from basic thread management, you will learn advanced synchronization techniques, how to use thread pools, and Java's concurrency-related classes in depth.

Scala allows you to write much more concise and robust code quickly, while still leveraging the experience you have gained as a Java developer. This course is designed for Java developers to quickly understand the overall look of Scala based on their existing Java knowledge. If you are an existing Java developer, you can learn Scala very easily.

Spring AI + JPA + MySQL Premium Reservation Agent Backend Development with 'Autonomous Behavior' Beyond Chatbots to Agents: The Definitive Guide to Tool Calling and Prompt Engineering

Learn the essential modern Java technologies of Lambda, Stream, and functional programming with Java, from the basics to the practical level, in depth.

An AI system that grades and reviews your code in 5 seconds - imagination becomes reality. This course is an all-in-one project that builds a **'GitHub PR Automatic Analysis and Grading Bot'** using Spring AI. When a student submits an assignment (Pull Request), the server detects it and AI analyzes the code changes (Diff). The grading results are then stored in the database, feedback is automatically posted as GitHub comments, and students can check their results on a dedicated dashboard. From backend to AI integration and frontend (Vaadin) - all with Java! This is the ultimate introductory guide for all developers who want to complete their own AI service from A to Z.

In [Java Practical Project: UI Edition], we will create a movie information application that operates solely on pure Java technology using JavaFX. This course is designed to help you deeply understand the "structure connecting screens and logic" by directly implementing UI event handling, asynchronous logic, and user interaction flows in Java before moving on to web and smartphone apps. You will train your structural thinking by separating business logic and UI through integration with Spring Core, and learn how to solve UI performance degradation issues that may occur when fetching movie information from external APIs using asynchronous processing. Through this, you will clearly understand the principles of data flow, event listeners, and thread-based asynchronous processing, elevating your understanding of the Java language itself to the next level. In short, this course is a "practical stage to experience the essence of UI and the core of asynchronous processing with Java before moving to the web." Do not forget that this is not a class for just typing along with code, but a learning experience where you can personally master the principles of connecting UI and logic.

This course is a video lecture that systematically covers the core modern JavaScript syntax essential for learning React.js and Vue.js frontend development. It is structured to help you develop efficient coding skills through ES6+ syntax, latest features, and practical examples that can be directly applied to work and learning.

Experience the power of Type Safe SQL with jOOQ!

You can quickly learn about virtual threads supported from spring boot 3.2.0 (+ JDK 21) and get hints on performance improvement in just 1 hour for free.

A Java advanced project course for beginner developers who want to develop practical skills! We'll build a console-based kiosk ordering system together using Spring Core, JdbcClient, and H2 DB.

Learn Springboot + ReactNative RestAPI Board Creation Faster Than Anyone Develop a CRUD server with Springboot and create your own board with ReactNative!!

This is a full-stack hands-on course where you will implement a ChatGPT clone from scratch. From Spring Boot server to React frontend | Neo + Essential This is not just a course where you simply follow along with the code; it guides you through actual service deployment so you can build a high-quality AI chatbot service.

This is a basic DFS lecture that explains the way a liberal arts major and working developer studied to get a job :) We have prepared a lecture where you can learn by solving problems yourself, with minimal boring theory lectures! After taking this lecture, you will be able to solve silver level DFS problems on your own according to Baekjoon standards.

IntelliJ IDEA Conf 2025 is an annual online conference hosted by JetBrains that provides valuable sessions for Java and Kotlin developers. It covers various topics including AI adoption, Spring Boot, Gradle, Kafka, database management, and also shares insights on cloud integration, secure coding, developer performance improvement, and advanced development techniques. This conference is open to both professional and beginner developers, offering opportunities to explore the latest technologies along with productivity tips for writing high-quality code faster.

What kinds of problems appear in coding tests these days? Solve “practical” problems yourself, reflecting the latest corporate coding test trends. We provide proven problems and solutions to effectively build your algorithm and problem-solving skills. (with Java)

Handling media (video, audio) on the web is now easier than ever! Learn the MediaStream API and WebRTC by following along step by step.

This is a lecture for people who are starting development for the first time. It's about programming thinking, which should come before development languages or UI frameworks.

Knowing design patterns will make it easier to learn not only Spring but also many other technologies and programming languages. It will also help you develop more flexible and reusable object-oriented software.