What Happens When You Hit a Spring Boot REST API Endpoint (Behind the Scenes)

Ramesh Fadatare

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4 min read

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May 6, 2025

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👋 Hey developers,

You’ve built a Spring Boot app. You’ve exposed a @GetMapping endpoint. You test it in Postman, and — boom — it works.

But have you ever asked:

“What really happens when I hit http://localhost:8080/api/products?”

This guide breaks down the entire request flow behind a Spring Boot endpoint — step by step — from the incoming HTTP request to the final response.

Let’s uncover the magic behind the scenes.

If you want to learn Spring Boot from scratch, here is a complete series on the Medium platform (text-based course):

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