- Spring Boot – Exception Handling
One @RestControllerAdvice, one error shape, every endpoint. Turning a validation failure into a field-by-field response the frontend can render, mapping your own exceptions to status codes, and why returning 404 instead of 403 for a foreign-owned resource is a security decision rather than a sloppy one.
- Python – Introduction
What Python actually is — a language and an interpreter, which is two things people use one word for. Why indentation is syntax rather than style, what dynamic typing buys you and costs you, where Python is used in 2026, and how its releases work.
- Packages
A package is a namespace. It groups related classes, prevents name collisions between unrelated libraries, and — through access modifiers — decides who can see what. Two classes called Order can coexist happily as long as they live in different packages. Declaring a package The package line must be…
- Static and Final Keywords
Two small keywords that get confused with each other constantly. They are unrelated: static means "belongs to the class, not to an object" , and final means "cannot be reassigned" . Neither implies the other. static fields: one copy, shared Access a static field through the class name —…
- Data Structures & Algorithms – Get Started
Start here. What this track covers and in what order, why it is written in Java 25, and how to run every example yourself with nothing but a JDK — no build tool and no dependencies. Also the one habit that separates people who can answer these questions from people who have only read about them.