SCT221-0064/2024 Advanced programming assignment

src/App.java

@@ -0,0 +1,5 @@
+public class App {
+    public static void main(String[] args) throws Exception {
+        System.out.println("Hello, World!");
+    }
+}

src/BankAccount.java

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+public class BankAccount {
+    private double balance;
+
+    public BankAccount(double initialBalance) {
+        this.balance = initialBalance;
+    }
+
+    public double getBalance() {
+        return balance;
+    }
+
+    public void deposit(double amount) {
+        balance += amount;
+    }
+
+    public void withdraw(double amount) {
+        balance -= amount;
+    }
+}

src/BaseTransaction.java

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+import java.util.Calendar;
+
+public class BaseTransaction implements TransactionInterface {
+    protected double amount;
+    protected Calendar date;
+    protected String transactionID;
+
+    // Constructor
+    public BaseTransaction(double amount, String transactionID) {
+        this.amount = amount;
+        this.date = Calendar.getInstance(); // Captures the current date/time
+        this.transactionID = transactionID;
+    }
+
+    @Override
+    public double getAmount() {
+        return amount; // [cite: 25]
+    }
+
+    @Override
+    public Calendar getDate() {
+        return date; // [cite: 26]
+    }
+
+    @Override
+    public String getTransactionID() {
+        return transactionID; // [cite: 27]
+    }
+
+    public void printTransactionDetails() { // [cite: 29]
+        System.out.println("Transaction ID: " + transactionID);
+        System.out.println("Date: " + date.getTime());
+        System.out.println("Amount: $" + amount);
+    }
+
+    public void apply(BankAccount ba) throws InsufficientFundsException { // [cite: 30]
+        System.out.println("Base transaction applied. No changes made to balance.");
+    }
+}

src/DepositTransaction.java

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+public class DepositTransaction extends BaseTransaction {
+
+    public DepositTransaction(double amount, String transactionID) {
+        super(amount, transactionID);
+    }
+
+    @Override
+    public void apply(BankAccount ba) throws InsufficientFundsException { // 
+        ba.deposit(amount);
+        System.out.println("Deposit of $" + amount + " applied. New balance: $" + ba.getBalance());
+    }
+}

src/InsufficientFundsException.java

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+public class InsufficientFundsException extends Exception {
+    public InsufficientFundsException(String message) {
+        super(message);
+    }
+}

src/Main.java

@@ -1,156 +1,63 @@
-import Lecture1_adt.*; // Import all classes from Lecture1_adt package to be used in this client code
-
-import java.util.Calendar;
-import java.util.GregorianCalendar;
-import java.util.ArrayList;
-import java.util.List;
-
-//TIP To <b>Run</b> code, press <shortcut actionId="Run"/> or
-// click the <icon src="AllIcons.Actions.Execute"/> icon in the gutter.
-/*
-* Client Code for accessing the Lecture1_adt.TransactionInterface.java module
- */
 public class Main {
-
-    public static void testTransaction1() {
-        Calendar d1 = new GregorianCalendar(); // d1 is an Object [Objects are Reference types]
-        Lecture1_adt.Transaction1 t1 = new Lecture1_adt.Transaction1(1000, d1); // amount and d1 are arguments
-
-        System.out.println(t1.toString());
-        System.out.println("Lecture1_adt.TransactionInterface Amount: \t " + t1.amount);
-        System.out.println("Lecture1_adt.TransactionInterface Date: \t " + t1.date);
-
-        // Please note that the Client Codes can access the data in the class directly through the dot operator
-        // This kind of exposure is a threat to both the Representation Independence and Preservation of Invariants
-    }
-
-
-    /** @return a transaction of same amount as t, one month later
-     * This is a PRODUCER of the class Lecture1_adt.Transaction2
-     * This code will help demostrate the Design exposures still present in transaction2 class
-     * */
-
-    public static Transaction2 makeNextPayment(Transaction2 t) {
-        Calendar d =  t.getDate();
-        d.add(Calendar.MONTH, 1);
-        return new Transaction2(t.getAmount(), d);
-    }
-
-    /*
-    Testing Transaction2 class
-     */
-    public static void testTransaction2() {
-
-        Calendar d1 = new GregorianCalendar();
-
-        Lecture1_adt.Transaction2 t = new Lecture1_adt.Transaction2(1000, d1);
-
-        Lecture1_adt.Transaction2 modified_t = makeNextPayment(t);
-
-        System.out.println("\n\nState of the Object T1 After Client Code Tried to Change the Amount");
-        System.out.println("Lecture1_adt.TransactionInterface Amount: \t "+modified_t.getAmount());
-        System.out.println("Lecture1_adt.TransactionInterface Date: \t "+modified_t.getDate().getTime());
-
-        System.out.println("\n\nHow does T2 Look Like?????");
-        System.out.println("Lecture1_adt.TransactionInterface Amount: \t "+modified_t.getAmount());
-        System.out.println("Lecture1_adt.TransactionInterface Date: \t "+modified_t.getDate().getTime());
-
-        /* Please note that Although we have solved the problem of Transaction1
-        * And client code can no longer use the dot (.) operator to directly access the data
-        * There is still some exposure especially if we pass an object of a previous Transaction2 to create a new Transaction2 object
-         */
-
-    }
-
-
-    /** @return a list of 12 monthly payments of identical amounts
-     * This code will help demostrate the Design exposures still present in transaction3 class
-     * */
-    public static List<Transaction3> makeYearOfPayments (int amount) throws NullPointerException {
-
-        List<Transaction3> listOfTransaction3s = new ArrayList<Transaction3>();
-        Calendar date = new GregorianCalendar(2024, Calendar.JANUARY, 3);
-
-
-        for (int i = 0; i < 12; i++) {
-            listOfTransaction3s.add(new Transaction3(amount, date));
-            date.add(Calendar.MONTH, 1);
+    public static void main(String[] args) {
+        System.out.println("========== STARTING TRANSACTION SYSTEM TESTS ==========");
+
+        // 1. Setup Bank Account
+        BankAccount account = new BankAccount(500.0);
+        System.out.println("Initial Balance: $" + account.getBalance());
+
+        // 2. Test DepositTransaction
+        System.out.println("\n--- 1. Testing Standard Deposit ---");
+        DepositTransaction deposit = new DepositTransaction(200.0, "TXN-DEP-001");
+        deposit.printTransactionDetails();
+        try {
+            deposit.apply(account);
+        } catch (InsufficientFundsException e) {
+            System.out.println("Error: " + e.getMessage());
         }
-        return listOfTransaction3s;
-    }
-
-    /*
-    Testing Transaction3 class
-     */
-    public static void testTransaction3() {
-
-        List<Transaction3> allPaymentsIn2024 = makeYearOfPayments(1000);
-
-        for (Transaction3 t3 : allPaymentsIn2024) {
 
-            // Display all the 12 Transactions
-            for (Transaction3 transact : allPaymentsIn2024) {
-                System.out.println("\n\n  ::::::::::::::::::::::::::::::::::::::::::::\n");
-                System.out.println("Lecture1_adt.TransactionInterface Amount: \t "+transact.getAmount());
-                System.out.println("Lecture1_adt.TransactionInterface Date: \t "+transact.getDate().getTime());
-            }
+        // 3. Test Standard Withdrawal (Success)
+        System.out.println("\n--- 2. Testing Standard Withdrawal ---");
+        WithdrawalTransaction withdrawal1 = new WithdrawalTransaction(100.0, "TXN-WIT-001");
+        withdrawal1.printTransactionDetails();
+        try {
+            withdrawal1.apply(account);
+        } catch (InsufficientFundsException e) {
+            System.out.println("Error: " + e.getMessage());
         }
 
-        /* Please Check all the 12 transactions displayed and hwo their dates look like
-         * Note that Although Transaction3 class resolves to an extent the exposure in Transaction2 class
-         * There is still some exposure especially if we pass an object of a previous Transaction3 to create a
-         * new Transaction3 object
-         */
-    }
-
-
-    /** @return a list of 12 monthly payments of identical amounts
-     * This code Show that by judicious copying and defensive programming we eliminate the exposure in Transaction3
-     * As defined in the constructor of Transaction4 class
-     * */
-
-    public static List<Transaction4> makeYearOfPaymentsFinal (int amount) throws NullPointerException {
-
-        List<Transaction4> listOfTransaction4s = new ArrayList<Transaction4>();
-        Calendar date = new GregorianCalendar(2024, Calendar.JANUARY, 3);
-
-
-        for (int i = 0; i < 12; i++) {
-            listOfTransaction4s.add(new Transaction4(amount, date));
-            date.add(Calendar.MONTH, 1);
+        // 4. Test Reversal (From Phase 2)
+        System.out.println("\n--- 3. Testing Transaction Reversal ---");
+        withdrawal1.reverse();
+
+        // 5. Test Exception Handling (From Phase 3)
+        System.out.println("\n--- 4. Testing Insufficient Funds Exception ---");
+        WithdrawalTransaction withdrawal2 = new WithdrawalTransaction(1000.0, "TXN-WIT-002");
+        try {
+            withdrawal2.apply(account);
+        } catch (InsufficientFundsException e) {
+            System.out.println("EXPECTED EXCEPTION CAUGHT: " + e.getMessage());
         }
-        return listOfTransaction4s;
-    }
-
-    /*
-    Testing Transaction3 class
-     */
-    public static void testTransaction4() {
-
-        /*
-         * Call the function to make all the Twelve transaction in a year of our business
-         */
-
-        List<Transaction4> transactionsIn2024 = makeYearOfPaymentsFinal(1200);
 
-        // Display all the 12 Transactions
-        for (Transaction4 transact : transactionsIn2024) {
-            System.out.println("\n\n  ::::::::::::::::::::::::::::::::::::::::::::\n");
-            System.out.println("Lecture1_adt.TransactionInterface Amount: \t "+transact.getAmount());
-            System.out.println("Lecture1_adt.TransactionInterface Date: \t "+transact.getDate().getTime());
+        // 6. Test Partial Withdrawal (From Phase 3 Overloaded Method)
+        System.out.println("\n--- 5. Testing Partial Withdrawal ---");
+        WithdrawalTransaction withdrawal3 = new WithdrawalTransaction(800.0, "TXN-WIT-003");
+        withdrawal3.apply(account, true); 
+
+        // 7. Test Polymorphism & Type Casting (Crucial Q4 Requirement)
+        System.out.println("\n--- 6. Testing Polymorphism & Type Casting ---");
+        // Creating a subtype object (DepositTransaction) but referencing it as the Base type
+        BaseTransaction polyTransaction = new DepositTransaction(50.0, "TXN-POLY-001");
+        polyTransaction.printTransactionDetails();
+
+        try {
+            // Because of late binding (polymorphism), this will run the DepositTransaction's apply() 
+            // method, NOT the BaseTransaction's generic apply() method.
+            polyTransaction.apply(account); 
+        } catch (InsufficientFundsException e) {
+            System.out.println("Error: " + e.getMessage());
         }
 
-        // Please Take a look at all the 12 transaction now and compare with the outputs of the Transaction3 class
-    }
-
-
-    public static void main(String[] args) {
-        // This is the client code
-        // Uncomment the following lines to test the class which you would like to test
-
-        // testTransaction1()
-        // testTransaction2()
-        // testTransaction3()
-        // testTransaction4()
+        System.out.println("\n========== TESTS COMPLETED ==========");
     }
 }