Merge pull request 'complete homework assignments' (#1) from develop into main

Reviewed-on: amirmt/HW-06-exceptions-and-file-handling#1

src/main/java/Main.java

@@ -6,31 +6,45 @@ import java.util.Scanner;
 
 public class Main {
     static ArrayList<Product> productCatalog = new ArrayList<>();
-    public static void loadProducts() throws IOException{
+
+    public static void loadProducts() throws IOException
+    {
         InputStream input = Main.class
                 .getClassLoader()
                 .getResourceAsStream("products.csv");
-        if (input == null) {
+
+        if (input == null)
+        {
             throw new IOException("products.csv not found");
         }
+
         Scanner scanner = new Scanner(input);
 
-        // TODO:
-        // - Read each line from products.csv
-        // - For each line, parse productId, name, and price
-        // - The format of the file is like this:
-        //      [productId],[name],[price]
-        // - Store Product objects in the productCatalog ArrayList
+        while (scanner.hasNextLine())
+        {
+            String line = scanner.nextLine();
+            String[] parts = line.split(",");
+
+            int productId = Integer.parseInt(parts[0]);
+            String name = parts[1];
+            double price = Double.parseDouble(parts[2]);
+
+            Product product = new Product(productId, name, price);
+            productCatalog.add(product);
+        }
+
+        scanner.close();
 
-        // NOTE
-        // - The data in products.csv is guaranteed to be valid.
     }
 
     public static void main(String[] args)
     {
-        try {
+        try
+        {
             loadProducts();
-        } catch (IOException e) {
+        }
+        catch (IOException e)
+        {
             System.err.println("Error reading products");
             System.out.println("Terminating the program...");
             return;

src/main/java/ReportGenerator.java

@@ -1,4 +1,9 @@
+import java.io.File;
+import java.io.FileNotFoundException;
 import java.util.List;
+import java.util.Scanner;
+import java.io.FileWriter;
+import java.io.IOException;
 
 public class ReportGenerator {
 
@@ -10,74 +15,94 @@ public class ReportGenerator {
     private double totalDiscountValue;
     private int totalInvalidLines;
 
-    public ReportGenerator(String ordersFilePath, List<Product> productList) {
+    public ReportGenerator(String ordersFilePath, List<Product> productList)
+    {
         this.ordersFilePath = ordersFilePath;
         this.productList = productList;
     }
 
     public void processFile()
     {
-        // TODO:
-        // 1. Open the order details CSV file
-        // 2. Read the file line by line
-        // 3. Split each line using comma delimiter
-        //      (each line is guaranteed to contain exactly two commas)
-        // 4. Each line contains exactly 3 values in the format:
-        //      [productId],[quantity],[discountPercent]
-        // 5. Attempt to convert values:
-        //      - productId -> int
-        //      - quantity -> int
-        //      - discountPercent -> int
-        //    NOTE:
-        //      - quantity and discountPercent may contain invalid characters
-        //        (e.g., letters instead of numbers).
-        //      - If parsing any value fails (NumberFormatException),
-        //        the entire line must be considered invalid.
-        //      - Use try-catch blocks and exception handling to safely
-        //        handle parsing and validation errors without stopping
-        //        the processing of the remaining lines.
-        // 6. Validate parsed values:
-        //      - productId must be greater than 0
-        //      - quantity must be greater than 0
-        //      - discountPercent must be between 0 and 99 inclusive
-        // 7. Look for a Product in productList that matches productId
-        // 8. If no Product with that ID exists in the catalog,
-        //      the entire line is considered invalid
-        // 9. If all values are valid and the product exists, calculate:
-        //      subtotal = quantity * product price
-        //      discountValue = subtotal * discountPercent / 100
-        //      finalCost = subtotal - discountValue
-        // 10. Update report totals:
-        //      - totalQuantity += quantity
-        //      - totalFinalCost += finalCost
-        //      - totalDiscountValue += discountValue
-        // 11. If any parsing error, validation failure, or missing product occurs:
-        //      - increment totalInvalidLines
-        //      - skip the line and continue processing the next line
-        // 12. Close all file resources
+        try
+        {
+            Scanner scanner = new Scanner(new File(ordersFilePath));
+
+            while (scanner.hasNextLine())
+            {
+                String line = scanner.nextLine();
+                String[] parts = line.split(",");
+
+                try
+                {
+                    int productId = Integer.parseInt(parts[0]);
+                    int quantity = Integer.parseInt(parts[1]);
+                    int discountPercent = Integer.parseInt(parts[2]);
+
+                    if ((productId <= 0 || productId > 9) || quantity <= 0 || (discountPercent < 0 || discountPercent > 99))
+                    {
+                        totalInvalidLines++;
+                        continue;
+                    }
+
+                    Product matchedProduct = null;
+
+                    for (Product p : productList)
+                    {
+                        if (p.getProductID() == productId)
+                        {
+                            matchedProduct = p;
+                            break;
+                        }
+                    }
+
+                    if (matchedProduct == null)
+                    {
+                        totalInvalidLines++;
+                        continue;
+                    }
+
+                    double subtotal = quantity * matchedProduct.getPrice();
+                    double discountValue = subtotal * (discountPercent / 100.0);
+                    double finalCost = subtotal - discountValue;
+
+                    totalQuantity += quantity;
+                    totalFinalCost += finalCost;
+                    totalDiscountValue += discountValue;
+
+                }
+                catch (NumberFormatException e)
+                {
+                    totalInvalidLines++;
+                }
+            }
+
+            scanner.close();
+
+        }
+        catch (FileNotFoundException e)
+        {
+            System.err.println("Orders file not found");
+        }
     }
 
     public void saveReport()
     {
-        // TODO:
-        // 1. Build a formatted report string
-        // 2. Include:
-        //      - total quantity
-        //      - total final cost
-        //      - total discount value
-        //      - total invalid lines
-        // 3. Create/open output report file (name it report.txt)
-        // 4. Write report string into file
-        // 5. Handle file writing exceptions
-        // 6. Close writer resources
+        String report = "========= SALES REPORT =========\n"
+                + "Total Quantity Sold: " + totalQuantity + "\n"
+                + "Total Final Cost: $" + String.format("%.2f", totalFinalCost) + "\n"
+                + "Total Discount Value: $" + String.format("%.2f", totalDiscountValue) + "\n"
+                + "Invalid Rows: " + totalInvalidLines + "\n"
+                + "================================";
 
-        /* Example Structure
-        ========= SALES REPORT =========
-        Total Quantity Sold: 42
-        Total Final Cost: $1520.75
-        Total Discount Value: $230.50
-        Invalid Rows: 3
-        ================================
-        */
+        try
+        {
+            FileWriter writer = new FileWriter("report.txt");
+            writer.write(report);
+            writer.close();
+        }
+        catch (IOException e)
+        {
+            System.err.println("Error writing report file");
+        }
     }
 }