How HTTP Requests Actually Travel Through Spring Boot Before Reaching Your Controller

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Many Spring Boot developers trigger API calls from tools like Postman without understanding the internal journey of each request. Before a controller method executes, the request passes through multiple infrastructure layers, starting with the operating system routing it to the port the application is listening on. Contrary to a common misconception, the controller is not the first component to handle an incoming request. Grasping this layered flow helps developers move beyond rote annotation usage toward a deeper understanding of the framework. A follow-up piece will cover how Spring Boot automatically starts an embedded Tomcat server before any request arrives.

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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