feat: Lesson17HW implement SavingsAccount

Author: lquinoa252

lesson_17/bank/bank_app/src/main/java/com/codedifferently/lesson17/bank/Account.java

@@ -0,0 +1,61 @@
+package com.codedifferently.lesson17.bank;
+
+import com.codedifferently.lesson17.bank.exceptions.InsufficientFundsException;
+import java.util.Set;
+
+/** Represents a bank account interface that defines common account operations. */
+public interface Account {
+
+  /**
+   * Gets the account number.
+   *
+   * @return The account number.
+   */
+  String getAccountNumber();
+
+  /**
+   * Gets the owners of the account.
+   *
+   * @return The owners of the account.
+   */
+  Set<Customer> getOwners();
+
+  /**
+   * Deposits funds into the account.
+   *
+   * @param amount The amount to deposit.
+   * @throws IllegalStateException If the account is closed.
+   * @throws IllegalArgumentException If the amount is not positive.
+   */
+  void deposit(double amount) throws IllegalStateException, IllegalArgumentException;
+
+  /**
+   * Withdraws funds from the account.
+   *
+   * @param amount The amount to withdraw.
+   * @throws InsufficientFundsException When there are not enough funds.
+   * @throws IllegalStateException If the account is closed or amount is not positive.
+   */
+  void withdraw(double amount) throws InsufficientFundsException, IllegalStateException;
+
+  /**
+   * Gets the balance of the account.
+   *
+   * @return The balance of the account.
+   */
+  double getBalance();
+
+  /**
+   * Closes the account.
+   *
+   * @throws IllegalStateException If the account cannot be closed.
+   */
+  void closeAccount() throws IllegalStateException;
+
+  /**
+   * Checks if the account is closed.
+   *
+   * @return True if the account is closed, otherwise false.
+   */
+  boolean isClosed();
+}

lesson_17/bank/bank_app/src/main/java/com/codedifferently/lesson17/bank/BankAtm.java

@@ -10,14 +10,14 @@
 public class BankAtm {
 
   private final Map<UUID, Customer> customerById = new HashMap<>();
-  private final Map<String, CheckingAccount> accountByNumber = new HashMap<>();
+  private final Map<String, Account> accountByNumber = new HashMap<>();
 
   /**
-   * Adds a checking account to the bank.
+   * Adds an account to the bank.
    *
    * @param account The account to add.
    */
-  public void addAccount(CheckingAccount account) {
+  public void addAccount(Account account) {
     accountByNumber.put(account.getAccountNumber(), account);
     account
         .getOwners()
@@ -27,13 +27,31 @@ public void addAccount(CheckingAccount account) {
             });
   }
 
+  /**
+   * Adds a checking account to the bank.
+   *
+   * @param account The checking account to add.
+   */
+  public void addAccount(CheckingAccount account) {
+    addAccount((Account) account);
+  }
+
+  /**
+   * Adds a savings account to the bank.
+   *
+   * @param account The savings account to add.
+   */
+  public void addAccount(SavingsAccount account) {
+    addAccount((Account) account);
+  }
+
   /**
    * Finds all accounts owned by a customer.
    *
    * @param customerId The ID of the customer.
    * @return The unique set of accounts owned by the customer.
    */
-  public Set<CheckingAccount> findAccountsByCustomerId(UUID customerId) {
+  public Set<Account> findAccountsByCustomerId(UUID customerId) {
     return customerById.containsKey(customerId)
         ? customerById.get(customerId).getAccounts()
         : Set.of();
@@ -46,7 +64,7 @@ public Set<CheckingAccount> findAccountsByCustomerId(UUID customerId) {
    * @param amount The amount to deposit.
    */
   public void depositFunds(String accountNumber, double amount) {
-    CheckingAccount account = getAccountOrThrow(accountNumber);
+    Account account = getAccountOrThrow(accountNumber);
     account.deposit(amount);
   }
 
@@ -57,18 +75,25 @@ public void depositFunds(String accountNumber, double amount) {
    * @param check The check to deposit.
    */
   public void depositFunds(String accountNumber, Check check) {
-    CheckingAccount account = getAccountOrThrow(accountNumber);
-    check.depositFunds(account);
+    Account account = getAccountOrThrow(accountNumber);
+
+    // Check deposits only work with checking accounts
+    if (!(account instanceof CheckingAccount)) {
+      throw new IllegalArgumentException("Check deposits are only allowed for checking accounts");
+    }
+
+    CheckingAccount checkingAccount = (CheckingAccount) account;
+    check.depositFunds(checkingAccount);
   }
 
   /**
    * Withdraws funds from an account.
    *
-   * @param accountNumber
-   * @param amount
+   * @param accountNumber The account number.
+   * @param amount The amount to withdraw.
    */
   public void withdrawFunds(String accountNumber, double amount) {
-    CheckingAccount account = getAccountOrThrow(accountNumber);
+    Account account = getAccountOrThrow(accountNumber);
     account.withdraw(amount);
   }
 
@@ -78,8 +103,8 @@ public void withdrawFunds(String accountNumber, double amount) {
    * @param accountNumber The account number.
    * @return The account.
    */
-  private CheckingAccount getAccountOrThrow(String accountNumber) {
-    CheckingAccount account = accountByNumber.get(accountNumber);
+  private Account getAccountOrThrow(String accountNumber) {
+    Account account = accountByNumber.get(accountNumber);
     if (account == null || account.isClosed()) {
       throw new AccountNotFoundException("Account not found");
     }

lesson_17/bank/bank_app/src/main/java/com/codedifferently/lesson17/bank/CheckingAccount.java

@@ -4,7 +4,7 @@
 import java.util.Set;
 
 /** Represents a checking account. */
-public class CheckingAccount {
+public class CheckingAccount implements Account {
 
   private final Set<Customer> owners;
   private final String accountNumber;
@@ -25,29 +25,17 @@ public CheckingAccount(String accountNumber, Set<Customer> owners, double initia
     isActive = true;
   }
 
-  /**
-   * Gets the account number.
-   *
-   * @return The account number.
-   */
+  @Override
   public String getAccountNumber() {
     return accountNumber;
   }
 
-  /**
-   * Gets the owners of the account.
-   *
-   * @return The owners of the account.
-   */
+  @Override
   public Set<Customer> getOwners() {
     return owners;
   }
 
-  /**
-   * Deposits funds into the account.
-   *
-   * @param amount The amount to deposit.
-   */
+  @Override
   public void deposit(double amount) throws IllegalStateException {
     if (isClosed()) {
       throw new IllegalStateException("Cannot deposit to a closed account");
@@ -58,12 +46,7 @@ public void deposit(double amount) throws IllegalStateException {
     balance += amount;
   }
 
-  /**
-   * Withdraws funds from the account.
-   *
-   * @param amount
-   * @throws InsufficientFundsException
-   */
+  @Override
   public void withdraw(double amount) throws InsufficientFundsException {
     if (isClosed()) {
       throw new IllegalStateException("Cannot withdraw from a closed account");
@@ -77,28 +60,20 @@ public void withdraw(double amount) throws InsufficientFundsException {
     balance -= amount;
   }
 
-  /**
-   * Gets the balance of the account.
-   *
-   * @return The balance of the account.
-   */
+  @Override
   public double getBalance() {
     return balance;
   }
 
-  /** Closes the account. */
+  @Override
   public void closeAccount() throws IllegalStateException {
     if (balance > 0) {
       throw new IllegalStateException("Cannot close account with a positive balance");
     }
     isActive = false;
   }
 
-  /**
-   * Checks if the account is closed.
-   *
-   * @return True if the account is closed, otherwise false.
-   */
+  @Override
   public boolean isClosed() {
     return !isActive;
   }

lesson_17/bank/bank_app/src/main/java/com/codedifferently/lesson17/bank/Customer.java

@@ -9,7 +9,7 @@ public class Customer {
 
   private final UUID id;
   private final String name;
-  private final Set<CheckingAccount> accounts = new HashSet<>();
+  private final Set<Account> accounts = new HashSet<>();
 
   /**
    * Creates a new customer.
@@ -41,20 +41,38 @@ public String getName() {
   }
 
   /**
-   * Adds a checking account to the customer.
+   * Adds an account to the customer.
    *
    * @param account The account to add.
    */
-  public void addAccount(CheckingAccount account) {
+  public void addAccount(Account account) {
     accounts.add(account);
   }
 
+  /**
+   * Adds a checking account to the customer.
+   *
+   * @param account The checking account to add.
+   */
+  public void addAccount(CheckingAccount account) {
+    addAccount((Account) account);
+  }
+
+  /**
+   * Adds a savings account to the customer.
+   *
+   * @param account The savings account to add.
+   */
+  public void addAccount(SavingsAccount account) {
+    addAccount((Account) account);
+  }
+
   /**
    * Gets the accounts owned by the customer.
    *
    * @return The unique set of accounts owned by the customer.
    */
-  public Set<CheckingAccount> getAccounts() {
+  public Set<Account> getAccounts() {
     return accounts;
   }