Module 9: Final Project – Bank Account Management System

This is the culmination of your journey. Let's assemble all the pieces into a complete, portfolio-ready application.

Putting It All Together

Throughout this course, we've built individual components in isolation: controllers, services, repositories, entities, and security configurations. In this final project module, our goal is to ensure that these components work together seamlessly as a single, cohesive application.

We will perform an end-to-end review of the system, verifying that data flows correctly through every layer of the application, from an incoming HTTP request to the database and back again. This is your opportunity to step back and appreciate the complete, functional system you have architected and built from the ground up.

End-to-End System Checklist

By the end of this module, you will have a fully functional application with the following features integrated and verified. Go through this checklist to ensure your project is complete.

  • Customer Management: APIs for creating new customers and viewing their details are fully functional.
  • Account Creation: A customer can have one or more bank accounts (savings/checking), and the relationship is correctly stored in the database.
  • Deposit / Withdraw / Transfer: All core transaction APIs are working, with proper business logic and validation (e.g., checking for sufficient funds).
  • Transactional Integrity: Complex operations like fund transfers are wrapped in @Transactional to ensure data consistency.
  • Transaction History: A persistent log of all transactions is created and can be retrieved for any given account.
  • Login & Authentication: A robust login system is in place using Spring Security, with user credentials stored securely (hashed) in the database.
  • Database Integration: All application data (customers, accounts, users, transactions) is correctly persisted in the H2 database (or another configured database like PostgreSQL).
  • API Testing: All API endpoints have been tested with Postman to ensure they behave as expected.

Code Review and Refactoring

In a professional software development team, no code is merged without a code review. This is the practice of having your peers read and critique your code to improve its quality, catch bugs, and share knowledge. Now, you will be your own peer reviewer.

Take some time to read through your own code. Don't just check if it works—check if it's clean, readable, and maintainable. Ask yourself these questions:

  • Clarity: Are my variable and method names descriptive? (e.g., `createAccountForCustomer` is better than `createAcc`).
  • DRY Principle: "Don't Repeat Yourself." Is there any duplicated code that could be extracted into a shared, reusable method?
  • Error Handling: Is my error handling consistent? Am I properly handling cases where an entity is not found (e.g., throwing a `ResourceNotFoundException`)?
  • Separation of Concerns: Does my Controller contain any business logic, or is it all correctly delegated to the Service layer? Is my Service layer free of any direct HTTP-related code?

Polishing Your Portfolio Project

This project is now a significant asset in your developer portfolio. To make the best impression on potential employers, a little polish goes a long way.

Create an Excellent `README.md`

The `README.md` file is the front page of your project on GitHub. It should be clear, concise, and professional. Make sure it includes:

  • A clear Project Title and a one-paragraph Description.
  • A list of the main Features (use the checklist from above!).
  • The Technologies Used (Java, Spring Boot, Spring Security, JPA/Hibernate, Maven, etc.).
  • Instructions on How to Run the Project Locally.
  • (Optional but highly recommended) API Documentation listing your endpoints, what they do, the expected request body, and a sample response.

Live Demo

As covered in the previous module, having a live, deployed version of your application (e.g., on Heroku) is incredibly impressive. It proves that you can not only write code but can also see a project through to completion and deployment.