Solution to practice midterm

DigitalWallet.java

public class DigitalWallet {

    private static double maxWithdrawalPct = .5;

    private long accountId;
    private long balance = 0;
    private TransactionHistory transactions = new TransactionHistory();

    public DigitalWallet(long accountId) {
        this.accountId = accountId;
    }

    public DigitalWallet(long accountId, int initialDeposit) {
        this(accountId);
        deposit(initialDeposit);
    }

    public long getAccountId() {
        return accountId;
    }

    public void deposit(long amount) {
        if(amount > 0) {
            balance += amount;
            transactions.addTransaction(amount);
        } else {
            System.out.println("Invalid deposit amount.");
        }
    }

    public void withdraw(long amount) {
        if(canWithdraw(amount)) {
            balance -= amount;
            transactions.addTransaction(-amount);
        } else {
            System.out.println("Invalid withdrawal amount");
        }
    }

    public boolean canWithdraw(double amount) {
        return amount > 0 && amount <= balance * DigitalWallet.maxWithdrawalPct;
    }

    public static double getMaxWithdrawalPct() {
        return maxWithdrawalPct;
    }

    public static void setMaxWithdrawalPct(double maxWithdrawalPct) {
        DigitalWallet.maxWithdrawalPct = maxWithdrawalPct;
    }

    //Question #3
    public void transferFunds(DigitalWallet other, long amount) {
      if(this.canWithdraw(amount)) {
          this.withdraw(amount);
          other.deposit(amount);
      }
    }

    // Needed for question #2. Existence assumed for test.
    public long getBalance() {
        return balance;
    }

    public TransactionHistory getTransactionHistory() {
        return this.transactions;
    }
}