The goal of our project is to provide demonstrate Web-based network database transaction. Our project will provide multiple web browser users with an interface which allows transactions similar to those provided by an Automated Teller Machine (ATM). The maximum number of users will be limited by the web server hosting this application, not the application itself. The users will be allowed to deposit, withdraw, and transfer balances between bank accounts held at different banks. A database of each bank's accounts will be stored in independent web accessible databases. The bank databases will be hidden from the user of the ATM simulation, but may be viewed in by a separate web browser session to verify correctness of the simulation.
The ATM simulation program may be started by opening the simulation's home page in a web browser. Upon start up, the user will be presented with an informational display and prompted to either request an account balance for one or two accounts. To make a balance inquiry, the user must enter the account number(s) the balance is desired for and select the Balance button on his display. (For this simulation, account numbers will be unique between banks, thus eliminating the need for a bank name to be provided with the account number.) Making the balance inquiry has the additional side effect of an implied begin transaction, therefor a new transaction will be started for each entry made form the simulation's home page.
If the balance inquiry successfully returns the account balance(s), the user will be allowed to request a deposit, withdrawl, or balance transfer. The user will be provided a display with the balance and prompted for the next action. If the inquiry fails, the transaction will be aborted. The user will be prompted with a failure indication, and then returned to the simulation's home page.
Once a successful balance inquiry has been completed, the user may choose to deposit money in the account of the inquiry. To deposit money into the account, the user must enter the amount of the deposit and choose the Deposit button on his display. The Deposit button will only be presented if the user is in a state where deposits are allowed.
Sending the deposit request has the additional side effect of an implied end transaction. If the deposit attempt is successful, the user will be given a success message and the after deposit account balance. If the deposit attempt is not successful, the user will be informed of the failure and returned to the home page.
Once a successful balance inquiry has been completed, the user may choose to withdraw money from the account of the inquiry. To withdraw money from the account, the user must enter the amount of the withdrawl and choose the Withdraw button on his display. The Withdrawl button will only be presented if the user is in a state where withdrawals are allowed.
Sending the withdrawl request has the additional side effect of an implied end transaction. If the withdrawl attempt is successful, the user will be given a success message and the after withdrawl account balance. If the withdrawl attempt is not successful, the user will be informed of the failure and returned to the home page. A withdrawl request which would cause a balance to go negative will not be allowed to succeed.
Once a successful balance inquiry has been completed for two accounts, the user may choose to transfer money from the first account of the inquiry to the second. To transfer money from the first account, the user must enter the amount of the transfer and choose the Transfer button on his display. The Transfer button will only be presented if the user is in a state where transfers are allowed.
Sending the transfer request has the additional side effect of an implied end transaction. If the transfer attempt is successful, the user will be given a success message and the after transfer account balance of both accounts. If the withdrawl attempt is not successful, the user will be informed of the failure and returned to the home page. A transfer request which would cause a balance of the account transferred from to go negative will not be allowed to succeed. It is not necessary for the accounts involve in the transfer to belong to the same bank in order for the transfer to succeed.
The user my abort a transaction by pressing the Abort button on his display. A transaction may be aborted by the user anytime between starting up and sending a deposit, withdrawl, or transfer request. These operations may not be aborted once they are forwarded to the transaction manager since they contain implied commits. Once a transaction is aborted the user will be transitioned back to the start up display where he may choose to start begin another transaction or perform another action with his web browser.