More Java, different ways to manipulate code

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.

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.

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.

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.

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.

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.

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.

The features added to Java 8 are widely used in APIs provided by Java as well as third-party libraries and frameworks such as Spring. If you are a Java developer in this era, you must know them. Make them your own technology easily and quickly through this lecture.

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.

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.

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

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.

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

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.

By looking at the process of creating the Spring Framework, we will find out the principles that will help you understand and use Spring well. Through this, we will also look at how the code of the application written by the developer should be created.

Aren't you at a loss as to where to start with backend development? Start backend development in one day with Juju!

Gradle Masterclass for Efficient Build Management – Learn how to automate complex builds and increase project productivity. This course covers the core concepts and practical application of Gradle in detail. You will be able to build a professional-level build environment in no time.

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)

This is a Java course for those who are new to programming. You can easily learn Java by following along with the code.

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

This course is a practical program where you will master Kotlin-based AI agent development by building your own coding agents. Using Koog, an AI framework built with Kotlin, you will learn step-by-step how to implement coding agents similar to Claude Code, Cursor, and Junie. Koog is more than just a simple server-side framework; it integrates seamlessly with Spring and offers the scalability to connect with various environments—including Android, iOS, Desktop, and Web—through Kotlin Multiplatform (KMP). By building intelligent agents that can read, analyze, modify, and generate code, you will gain hands-on experience in AI agent architecture, strategy, context handling, and tool integration.

This course is a practical-focused learning program for JWT-based token authentication and security enhancement techniques that are essential in modern web service environments. Using Spring Boot 3, Spring Security 6, and React, you'll implement secure login systems and cover comprehensive security practices including XSS·CSRF countermeasures, HTTPS implementation, token reissuance and revocation strategies, and secure secret key management. Additionally, you'll practice real service-level environment configuration through AWS build·deployment and performance optimization using Redis, and the complete project source code provided in the course can be directly applied to real-world work.

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

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.

This course is for those preparing for coding tests in Java. It covers the top 10 topics that are most frequently tested in coding tests. It is structured step by step from basic to intermediate problems linked to the topic, so if you follow it step by step, you will get good results.

In this course, rather than directly covering theory, you will learn how to effectively use Redis in code through hands-on practice.

Learning about various communication techniques and understanding their differences helps you develop the ability to select and implement the most appropriate communication method.

Did you give up while studying Spring? Even complete beginners new to coding and non-majors can make it from JSP to Spring Boot without giving up - we'll open the path to Spring Boot for you.

Learn Java-based data structures and algorithms, and grow into a competitive coding expert with practical problems!

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.

Experience the power of Type Safe SQL with jOOQ!

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.

Learn the process of application development/release/update all at once through the Android Brainwashing Classroom. Learn the basics of JAVA and learn the distribution and update process while actually building an Android app. Implement the core functions of In★Gram yourself through practice. You can get started even if you don't know programming.