A banking simulation system requires robust handling of finanncial transactions and client data. The core architecture typically revolves around entity classes representing accounts and a controller class managing business logic.

Core Components

The system is divided into four primary functional areas:

1. Client Profile Handling: Menages creation, updates, and removal of account holder details.
2. Transaction Processing: Handles crediting and debiting of funds.
3. Fund Transfers: Facilitates movement of capital between distinct accounts.
4. Reporting: Provides current ledger status and transaction history retrieval.

Implementation Details

Account Entity

The BankAccount class encapsulates state and behavior for individual accounts. It includes validatoin to prevent invalid financial operations.

public class BankAccount {
    private String accountHolder;
    private String id;
    private double ledgerBalance;

    public BankAccount(String holder, String accountId, double initialFunds) {
        this.accountHolder = holder;
        this.id = accountId;
        this.ledgerBalance = initialFunds;
    }

    public void credit(double amount) {
        if (amount > 0) {
            this.ledgerBalance += amount;
        }
    }

    public boolean debit(double amount) {
        if (amount > 0 && this.ledgerBalance >= amount) {
            this.ledgerBalance -= amount;
            return true;
        }
        return false;
    }

    public void wireTransfer(BankAccount recipient, double amount) {
        if (this.debit(amount)) {
            recipient.credit(amount);
        }
    }

    public double checkFunds() {
        return this.ledgerBalance;
    }
}

System Entry Point

The CoreBankingEngine class demonstrates the interaction between multiple account instances. It initializes data, executes transactions, and outputs the final state.

public class CoreBankingEngine {
    public static void main(String[] args) {
        BankAccount userOne = new BankAccount("Alice", "ACC-001", 1000.0);
        BankAccount userTwo = new BankAccount("Bob", "ACC-002", 500.0);

        userOne.credit(500.0);
        userTwo.debit(200.0);
        userOne.wireTransfer(userTwo, 300.0);

        System.out.println("ACC-001 Remaining: " + userOne.checkFunds());
        System.out.println("ACC-002 Remaining: " + userTwo.checkFunds());
    }
}