Spring AI + RAG: Build Production-Grade AI with Your Data -(2026)

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.

Legacy Java Code, The Most Practical Way to Fix It "Without Breaking" The reason refactoring is scary isn't because you don't understand the principles, but because you don't know how far you can trust your IDE. In this course, 👉 Using *only the refactorings guaranteed by IntelliJ IDEA* 👉 You'll develop **the sense to improve production code quickly and safely**.

"The Era of Coding with AI: A New Productivity Paradigm for Java Developers" This course is a practical Cursor AI utilization guide for Java developers. Beyond simply copying AI-generated code, you'll learn Vibe Coding methods that maximize development efficiency through collaboration with AI. By leveraging Cursor's powerful code understanding, refactoring, and documentation features, you'll master AI coding workflows step by step that can be immediately applied to real-world projects. In an era where AI writes code for us, "developers who can effectively work with AI" now have the competitive edge. Start your upgraded development experience as a Java developer with this course.

Learn the easiest way to handle AI with Spring AI. Let's learn Spring AI by building a RAG chatbot.

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.

This course covers how to set up multi-module projects from scratch using Kotlin and Spring Boot. It proceeds with a hands-on approach, covering everything from the basic concepts of modularization to Gradle configuration, managing dependencies between modules, and actual application development. If you are a beginner or intermediate developer looking to learn the fundamentals and practical application of multi-modules, please refer to this course.

Stop copy-pasting code! 🙅‍♂️ This is a "real" conceptual lecture that dives deep into everything from how agents work to their architecture and design philosophy. Beyond just learning how to build them, I will help you develop an eye for designing entire systems. Build a solid foundation here that remains unshakable amidst the technology trends of 2026! 🧠✨

OpenAI Practical Application Course, where you directly implement various AI functions such as text, image, voice, translation, and content review in a Java environment.

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.

If you have just finished the Java Basics book or are a Java beginner, I expect that through this course you will learn design patterns and be able to program with more efficient code when programming using Java.

Experience the power of Type Safe SQL with jOOQ!

SQL data analysis! We will teach you how to solve practical problems that are applicable in the field, quickly and easily!

Let's create a dashboard by visualizing various data.

My 14-day use, starting right after release: Claude Code! (AI Coding) - Immediately applicable to job seekers and pros! I'll tell you right away why I recommend it to everyone.

I have created an 'Introduction to Elasticsearch' course that is easy for non-majors to understand and can be applied immediately in practice!

This course focuses more on data modeling through entity design than on JPA technical explanations. Based on the principle that solid DB design is the foundation of application development, we analyze various design patterns—such as one-to-many, many-to-many, inheritance, and collections—alongside business scenarios. You will learn by directly observing the process of code being transformed into actual tables on screen. To ensure immediate practical application, we provide business use cases, source code, and test codes for each design pattern.

I'll show you how Java backend developers using IntelliJ can maximize productivity with Claude Code. In particular, I'll help you completely solve the Vibe coding environment issues that Windows users experience.

This is a lecture using the only domestic e-government framework and Layered Architecture, which are widely used in practice but not available in Korea. In this lecture, we will learn how to build the backend and server side of web development using the Spring Framework and the e-government standard framework.

The era of 'your own platform CEO' begins, even for IT beginners, with just an idea, using AI and GNUBOARD! We'll demonstrate the full development process from planning to deployment, and share diverse monetization methods like ads and shopping malls. Start your online business now!

If you have started Java development but feel overwhelmed when trying to solve a problem, it is time to study design patterns. I will explain 10 of the GoF design patterns that I personally use the most.