Spring Security Framework Practical Project Part.2 – Advanced Validation & Update/Delete Implementation

Obsidian is not just a simple note-taking app, but a powerful Second Brain tool that allows you to systematically connect knowledge and information for long-term use. However, many users often give up midway due to the difficulties of initial setup, the complexity of utilizing plugins, and disorganized note structures. This course is designed to directly solve these problems. Based on the instructor's experience in building knowledge management, project management, learning records, and productivity automation using Obsidian, this course provides step-by-step guidance on where to start, how to structure your system, and which features to use when. Starting from basic installation and settings, you will understand metadata, frontmatter, and Markdown structures. You will learn through practical examples of daily, weekly, and monthly note systems, template automation, and core plugins such as Tasks, Dataview, and QuickAdd. Furthermore, the course covers Zettelkasten-style note linking, project management, voice memo automation, and integration with external services, allowing students to apply these techniques immediately to their own environments. Through this course, students will integrate scattered information into a single system and complete their own Second Brain that can be continuously utilized across learning, work, and projects.

This course is Part 1 of a series designed to teach you how to apply the Spring Security framework to real-world projects step-by-step. Rather than just explaining simple theories, you will directly implement features based on an actual TodoApp project, such as saving Writer information to the database, setting up method-level authentication and authorization, and restricting post registration on template pages. Additionally, you will learn how to implement password rules and complex validation logic used in practice by utilizing the @Pattern regular expression (intermediate) from the Validation library. The course explains the parts students find most difficult—"the difference between authentication and authorization," "understanding DB integration structures," and "how to apply method security"—in an easy-to-understand manner by following the actual code flow. The curriculum is focused on building practical application skills through a structured approach of Theory → Code Modification → Testing → Result Verification.

This course is a comprehensive curriculum designed for everyone from beginners encountering big data analysis for the first time to learners looking to strengthen their practical skills. Starting with the history of data and industry trends, it systematically covers the entire flow of big data analysis, including data collection, preprocessing, storage, analysis, visualization, statistical analysis, and deep learning techniques. Many learners face difficulties such as "not being able to see the big picture of data analysis" or "knowing the theory but not knowing how to apply it in practice." To solve these problems, this course is structured in the order of Concept → Process → Analysis Technique → Result Interpretation and Application, clearly explaining why each step is necessary and how it connects to real-world tasks. This course goes beyond basic theory and focuses on mastering the mindset and analytical workflow that can be directly applied to actual data analysis projects and professional work.

This course is designed to help you learn MySQL databases and SQL step-by-step, from the absolute basics to a professional level. It covers database concepts, relational models, SQL syntax, queries, conditions, sorting, functions, joins, subqueries, and indexes, with a focus on practical examples. The curriculum is structured so that you can understand concepts many students find difficult (such as joins, subqueries, and group functions) by following along directly. With a flow of Theory → Practice → Summary, this course ensures you can complete it until the end without getting stuck. Whether you are new to SQL or want to brush up on the basics, you will gain database skills that can be applied immediately in the workplace.

Do you want to implement marketing automation but don't know where to start? Are you struggling with CRM, email marketing, and AI tools operating in silos, or seeing customer data pile up without an increase in conversion rates? This course guides you from start to finish on how to create a marketing automation system that "actually leads to sales" using CRM and Generative AI. By integrating practical tools such as ChatGPT, Zapier, Kit (ConvertKit), ElevenLabs, and HeyGen, you will build a hyper-personalized CRM workflow that segments customers → automatically delivers personalized messages → and maximizes conversion rates. Consisting of field-proven cases and step-by-step practices rather than just theory, even beginners with no marketing experience can build a complete CRM automation system by following this course.

This is a [Backend, Resume Enhancement] class prepared for job seekers and junior developers.

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.

From small projects to practicing structure building! A hands-on, mini-project-based introductory course for those who lack experience in Java object-oriented design and practice. From the basics to structural thinking, improve your skills by implementing a Java application from start to finish.

This course is a course where you can learn the Spring Framework. Most courses only introduce the Spring MVC Project, so you will not be able to properly understand the terms, concepts, and operating principles, and you will learn without knowing how it works.

Learn how to implement integrated regular and social logins using Spring Boot and React. Build a login system in both MPA and SPA environments and practice JWT and OAuth2 authentication. Understand and implement the entire login flow through example projects applicable directly to real-world scenarios.

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.

We develop a chat service using web socket/stomp and springboot. We also configure a simple screen using vue.js, which is a relatively easy framework. We also configure multi-server scalability design using redis pub/sub.

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.

Through this lecture, you can learn about the characteristics and background of the Kotlin language, grammar and operation principles, usage examples, and things to be careful of when using Java and Kotlin together.

Learn practical core Java object-oriented concepts easily via example code.

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

If you learned about grammar and component types in the ExtJS basic course, In the practical/application section, we will create a simple practice program along with server connection.

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 course proceeds in stages, similar to the actual work, by learning and applying the necessary knowledge while configuring the infrastructure.

Create a desktop app with minimal theory! Anyone can start creating an app even without programming experience!

Course Summary: This course teaches Java and Spring Boot developers how to design, build, and maintain Retrieval-Augmented Generation (RAG) systems at production level. Using Spring AI, PostgreSQL, and Redis, you will learn how to create robust pipelines for ingestion, chunking, embeddings, and retrieval, while orchestrating LLM behavior with reliable prompts. I share my backend engineering experience to help students solve common challenges: data inconsistency, inefficient retrieval, and unreliable prompts. By the end, you will be able to build a fully functional and maintainable internal knowledge assistant, with scalable, production-ready code.

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

I highly recommend Spring AI to developers using Spring Boot and React, as well as those considering the introduction of AI systems in corporate environments. This course goes beyond a simple introduction to libraries; it helps you understand the core concepts and internal structure of Spring AI, and strengthens your practical implementation skills through various hands-on examples. The course is based on Spring AI version 1.1.x and provides continuous technical support and expansion strategies to ensure you can adapt to future version upgrades. Furthermore, we expand the practical value of Spring AI technology by utilizing MCP (Model Context Protocol) to achieve cross-domain context integration, AI linkage in distributed environments, and AI architecture design suitable for enterprise environments. With the goal of building AI systems that can actually be deployed in corporate settings, this will serve as a practical guide that balances theory and hands-on experience.

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