Github repository for JAVA GUI: https://github.com/reazwrahman/stock-manager-gui

Github repository for Spring Boot REST API: https://github.com/reazwrahman/stock-manager-api

API is self-hosted at: https://stock-manager.reaz-projects.uk/usage

A quick 2 minutes demo: https://youtu.be/sXTsvaIcSoE?si=GExVt1zk8LA-qmLY

I built this stock portfolio tracker to solve a problem that has been on my mind for a long time – trying to see all my investments in one place. Like many casual investors, I had stocks scattered across Robinhood, Vanguard, and other platforms, making it tough to get a complete picture of each stock’s performance in comparison to others.

 

My solution has two main parts: a Java desktop app with a simple GUI where I can manually enter my stock details, and a Spring Boot API that does the backend calculations. When I input a stock, the backend grabs real-time price data and calculates my returns. I added some features like an in-memory cache to avoid hammering external APIs and implemented multithreading to handle lots of stock requests simultaneously without slowing things down.

I designed it with future expansion in mind: both components heavily use various creational, structural and behavioral design patterns. I am also planning to add a web UI later down the road that will easily integrate with the API.  

GUI Screenshots:  

 

Spring Boot API: