Complete Spring 7 & Spring Boot 4 course from beginner to Advance using first thought principle.
Curated by: Coder Army (29 videos)
In this video, we will understand how configuration works in Spring Boot using application.properties. Till now, we have written values directly inside Java classes. But in real applications, values like payment provider, retry count, timeout, database URL, API keys, and feature flags should not be hardcoded inside business logic. That is why Spring Boot provides externalized configuration. In this lecture, we will learn how Spring Boot automatically reads application.properties, how to inject values using @Value, and how to bind grouped properties using @ConfigurationProperties. We will also understand how to run code in a Spring Boot application when we do not have a controller, endpoint, browser request, or Postman request. For that, we will explore CommandLineRunner and ApplicationRunner. Topics Covered What is application.properties? Why should we avoid hardcoded values? What is externalized configuration? application.properties vs application.yml How Spring Boot loads configuration values Using @Value to inject properties Default values with @Value Problem with too many @Value annotations Introduction to @ConfigurationProperties Relaxed binding in Spring Boot @Value vs @ConfigurationProperties Why we need Runner interfaces Why not manually call beans from main() CommandLineRunner explained ApplicationRunner explained Difference between CommandLineRunner and ApplicationRunner Complete Spring Boot startup flow This video is part of our Spring Boot beginner-friendly series where we are learning Spring Boot step by step from first principles. Best For Spring Boot beginners Java backend developers Students learning Spring Framework Anyone confused about Spring Boot configuration Anyone learning Spring Boot without directly jumping into web APIs JAVA Beginner to Advance Series : https://youtube.com/playlist?list=PLQEaRBV9gAFsR15tNo2QLF9d2qc-c018p&si=lNuF5lyt4nKz9Up7 Join System Design WhatsApp Group: https://www.whatsapp.com/channel/0029VbBF1XKF1YlMyYuPM23s Code and Notes: Github : https://github.com/adityatandon15/Spring-Framework-Full-Course We have paid courses on DSA, Web Development , Blockchain, System Design & GenAI. Join Courses: https://strikes.in/ Coder Army Website: https://coderarmy.in/#home Coder Army App: https://play.google.com/store/apps/details?id=com.rohit.negi Connect with Aditya Tandon Instagram : https://www.instagram.com/adityatandon2 LinkedIn : https://www.linkedin.com/in/adityatandon2 Twitter : https://x.com/adityatandon02 Timestamps: