2023年11月25日

Java代写 | An Online Payment Service

本次英国代写主要为制作Java在线支付系统的assignment

1. Introduction

This assignment is about the design and implementation of a web-based, multi-user payment service using Java Enterprise Edition (Java EE) technologies. The system is a much simplified version of PayPal. Through a JSF-based web interface, users should be able to send money to other registered users (e.g. using their registered email address as their unique identifier), request money from other registered users and manage their own account (e.g. look at their recent transactions). Super-users (i.e. admins) should be able to access all user accounts and transactions. Optionally, you will deploy your application on the cloud (e.g. on Amazon AWS, Microsoft Azure, or any similar infrastructure).

After successfully completing the assignment, you will have demonstrated that you can:

  • design and implement user interfaces using Java Server Faces
  • design and implement business logic using enterprise Java beans (EJBs)
  • design and implement a secure multi-user system

 

2. Project Description

Online payment services, such as PayPal, allow users to connect their online accounts to their bank accounts, debit and credit cards. In such systems, users are usually able to transfer money from their bank accounts to the online account, receive payments to this account from other users, push money from the online account to their bank accounts etc.

For simplicity, we will assume that, for this project, all registered users start with a specific amount of money (e.g. £1000 pounds) and no connections to bank accounts exist.

Note: this is pretended money and no connection to real sources of money should exist.

Each user has a single online account whose currency is selected upon registration. A user can select to have their account in GB Pounds, US dollars or Euros. In that case, the system should make the appropriate conversion to assign the right initial amount of money (e.g. if the baseline is £1000, then the initial amount should be 1000 * GBP_to_USD_rate US dollars).

A user can instruct the system to make a direct payment to another user. If this request is accepted (i.e. the recipient of the payment exists and there are enough funds), money is transferred (within a single Java EE transaction) to the recipient immediately. A user should be able to check for notifications regarding payments in their account.

A user can instruct the system to request payment from some other user. A user should be able to check about such notifications for requests for payment. They can reject the request, or, in response to it, make a payment to the requesting user.

Users can access all their transactions, that is, sent and received payments and requests for payments as well as their current account balance.

An administrator can see all user accounts and all transactions.

Currency conversion must be implemented by a separate RESTful web service (see Section 3.3). The actual exchange rates will be statically assigned (hard-coded) in the RESTful service source code.