tavwo/virtual-wallet-fintech-web-application

Purpose and Runtime

Virtual Wallet is a Spring Boot fintech application for wallet creation, card-backed funding, user-to-user transfers, donations, referrals, and transaction history. It serves both server-rendered Thymeleaf pages and REST endpoints. Boot entry point: src/main/java/a16team1/virtualwallet/VirtualWalletApplication.java.

Delivery Surfaces

MVC controllers drive browser flows for home/dashboard, accounts, wallets/cards, PIN, transactions, assistant, and admin pages: src/main/java/a16team1/virtualwallet/controllers/mvc/TransactionsController.java, src/main/java/a16team1/virtualwallet/controllers/mvc/UserAccountController.java, src/main/resources/views/transaction-history.html. REST exposes JWT authentication, transaction/user APIs, and assistant integration: src/main/java/a16team1/virtualwallet/controllers/rest/JwtAuthenticationController.java, src/main/java/a16team1/virtualwallet/controllers/rest/TransactionsRestController.java.

Domain and Persistence Boundary

Core persistent aggregates are users, wallets, payment instruments/cards, transactions, categories, and expiring verification/invitation tokens: src/main/java/a16team1/virtualwallet/models/User.java, src/main/java/a16team1/virtualwallet/models/Wallet.java, src/main/java/a16team1/virtualwallet/models/Transaction.java. Service implementations contain application rules and depend on repository contracts/implementations, which form the Hibernate data-access boundary: src/main/java/a16team1/virtualwallet/services/TransactionServiceImpl.java, src/main/java/a16team1/virtualwallet/repositories/contracts/TransactionRepository.java, src/main/java/a16team1/virtualwallet/repositories/TransactionRepositoryImpl.java.

Money Movement Flow

Funding starts from a card/payment instrument and creates funding transactions; transfers debit one wallet and credit another, while donations route an added amount to designated donation-project accounts. Transaction state, references, direction/type/status, DTO conversion, and idempotency are explicit concerns: src/main/java/a16team1/virtualwallet/services/PaymentInstrumentServiceImpl.java, src/main/java/a16team1/virtualwallet/services/IdempotencyManager.java, src/main/java/a16team1/virtualwallet/utilities/TransactionReferenceGenerator.java. Large transfers require a verification-token confirmation/expiry stage: src/main/java/a16team1/virtualwallet/models/TransactionVerificationToken.java, src/main/java/a16team1/virtualwallet/services/email_tokens/TokenServiceImpl.java.

Identity, Authorization, and User Safeguards

Spring Security configuration supports browser authentication plus JWT-filtered API access; user details are loaded through custom security services. MFA and PIN workflows add separate verification gates, including an MVC interceptor that enforces PIN setup: src/main/java/a16team1/virtualwallet/configuration/SecurityConfig.java, src/main/java/a16team1/virtualwallet/security/JwtRequestFilter.java, src/main/java/a16team1/virtualwallet/interceptors/PinSetupInterceptor.java. Registration, referral invitations, and account/transaction confirmation use email token services: src/main/java/a16team1/virtualwallet/services/email_tokens/EmailVerificationServiceImpl.java, src/main/java/a16team1/virtualwallet/services/email_tokens/EmailSenderServiceImpl.java.

Presentation and Mapping Boundary

Controllers translate request/form DTOs into services and prepare models for Thymeleaf; mappers isolate domain-to-presentable DTO conversion. Shared layouts, pages, and static browser assets are packaged with the application: src/main/java/a16team1/virtualwallet/utilities/mappers/TransactionDtoMapper.java, src/main/resources/views/fragments/layout.html, src/main/resources/static/js/wallet-assistant.js.

Infrastructure and External Dependencies

The application uses Java/Spring Boot, Spring MVC/Security, Hibernate, and MariaDB. Hibernate/web/template configuration and schema seed scripts establish runtime persistence: src/main/java/a16team1/virtualwallet/configuration/HibernateConfig.java, src/main/resources/application.properties, src/main/resources/sql/schema.sql. Container and deployment artifacts indicate Docker-based execution and CI deployment: Dockerfile, docker-compose.yml, .github/workflows/deploy.yml. The README identifies an external banking API for card top-ups; its repository-facing adapter is src/main/java/a16team1/virtualwallet/repositories/ExternalCardRepositoryImpl.java.