- Spring Boot – File Upload
Accepting a MultipartFile, the size limits you have to raise in two different places, and validating what was actually uploaded rather than trusting the filename or the content type the browser claimed. Ends with streaming a file back out again.
- Python – Data Types
The types you will use every day — int, float, str, bool, None — plus what a variable really is in Python, why `is` and `==` are not the same question, and the integer division and float rounding traps that bite everyone once.
- Exception Handling
An exception is Java's way of saying "I cannot continue, and here is exactly why". Handling them well is mostly about restraint: catching only what you can actually do something about, and never hiding what you cannot. try , catch , finally The try block holds code that might fail. The catch runs…
- React Native – Modals, Sheets and Overlays
React Native's `Modal` is a real native window, which is why there is no `createPortal` in a React Native codebase — the z-index wars simply do not happen. Building a bottom sheet, the three things a web modal library gave you for free and you now wire by hand (Android's back button, tap-the-backdrop, the keyboard), and toasts that need no portal at all.
- Collections
Collections are the containers you reach for in every program: a list of orders, a set of tags, a map from id to customer. Java gives you four shapes and several implementations of each. Picking one should take about five seconds, and this post is mostly about making that true. The four shapes…