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🌱 Spring Boot + PostgreSQL – Complete Learning Notes

1️⃣ Creating a New Spring Boot Project (Spring Initializr)

Configuration chosen:

• Project: Maven
• Language: Java
• Spring Boot: Default (recommended for stability)
• Dependencies:
  • Spring Web → To create REST APIs (controllers, endpoints)
  • Spring Data JPA → To interact with databases using Java objects
  • PostgreSQL Driver → To connect Java application with PostgreSQL DB

👉 Spring Initializr auto-generates a ready-to-run project with correct folder structure and config.

2️⃣ Application Entry Point (Main Class)

This is the starting point of the Spring Boot application.

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

🔹 What do these imports do?

1. @SpringBootApplication

This is a meta-annotation (combines 3 annotations):

• @Configuration → Marks this class as a configuration class