Merge PR 'HW-06-exceptions-and-file-handling' (#1) from develop into main

Full Mark

src/main/java/Main.java

@@ -14,16 +14,20 @@ public class Main {
             throw new IOException("products.csv not found");
         }
         Scanner scanner = new Scanner(input);
-
+        try{
-        // TODO:
+            while(scanner.hasNextLine()){
-        // - Read each line from products.csv
+                String line = scanner.nextLine();
-        // - For each line, parse productId, name, and price
+                String [] parts = line.split(",",3);
-        // - The format of the file is like this:
+                int productId = Integer.parseInt(parts[0]);
-        //      [productId],[name],[price]
+                String name = parts[1];
-        // - Store Product objects in the productCatalog ArrayList
+                double price = Double.parseDouble(parts[2]);
-
+                Product product = new Product(productId , name , price);
-        // NOTE
+                productCatalog.add(product);
-        // - The data in products.csv is guaranteed to be valid.
+            }
+        }finally {
+            scanner.close();
+            input.close();
+        }
     }
 
     public static void main(String[] args)

src/main/java/ReportGenerator.java

@@ -1,4 +1,9 @@
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileWriter;
+import java.io.IOException;
 import java.util.List;
+import java.util.Scanner;
 
 public class ReportGenerator {
 
@@ -15,69 +20,105 @@ public class ReportGenerator {
         this.productList = productList;
     }
 
-    public void processFile()
+    public void processFile(){
-    {
+        File file = new File(ordersFilePath);
-        // TODO:
+
-        // 1. Open the order details CSV file
+        try (Scanner scanner = new Scanner(file)){
-        // 2. Read the file line by line
+            while (scanner.hasNextLine()){
-        // 3. Split each line using comma delimiter
+                String line = scanner.nextLine();
-        //      (each line is guaranteed to contain exactly two commas)
+                if (line.trim().isEmpty()){
-        // 4. Each line contains exactly 3 values in the format:
+                    continue;
-        //      [productId],[quantity],[discountPercent]
+                }
-        // 5. Attempt to convert values:
+                String [] parts = line.split(",",3);
-        //      - productId -> int
+
-        //      - quantity -> int
+                if(parts.length !=3){
-        //      - discountPercent -> int
+                    totalInvalidLines++;
-        //    NOTE:
+                    continue;
-        //      - quantity and discountPercent may contain invalid characters
+                }
-        //        (e.g., letters instead of numbers).
+
-        //      - If parsing any value fails (NumberFormatException),
+                int productId = 0;
-        //        the entire line must be considered invalid.
+                int quantity = 0;
-        //      - Use try-catch blocks and exception handling to safely
+                int discountPercent = 0;
-        //        handle parsing and validation errors without stopping
+                boolean lineValid = true;
-        //        the processing of the remaining lines.
+
-        // 6. Validate parsed values:
+                try{
-        //      - productId must be greater than 0
+                    productId = Integer.parseInt(parts[0].trim());
-        //      - quantity must be greater than 0
+                }catch (NumberFormatException e){
-        //      - discountPercent must be between 0 and 99 inclusive
+                    lineValid = false;
-        // 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
+                try{
-        // 9. If all values are valid and the product exists, calculate:
+                    quantity = Integer.parseInt(parts[1].trim());
-        //      subtotal = quantity * product price
+                }catch (NumberFormatException e){
-        //      discountValue = subtotal * discountPercent / 100
+                    lineValid = false;
-        //      finalCost = subtotal - discountValue
+                }
-        // 10. Update report totals:
+
-        //      - totalQuantity += quantity
+                try{
-        //      - totalFinalCost += finalCost
+                    discountPercent = Integer.parseInt(parts[2].trim());
-        //      - totalDiscountValue += discountValue
+                }catch (NumberFormatException e){
-        // 11. If any parsing error, validation failure, or missing product occurs:
+                    lineValid = false;
-        //      - increment totalInvalidLines
+                }
-        //      - skip the line and continue processing the next line
+
-        // 12. Close all file resources
+                if (lineValid){
+                    if (productId <= 0 || quantity <=0 || discountPercent <0 ||discountPercent >99){
+                        lineValid = false;
+                    }
+                }
+
+                Product matchingProduct = null;
+
+                if(lineValid){
+                    for(Product product : productList){
+                        if(product.getProductID() == productId){
+                            matchingProduct = product;
+                            break;
+                        }
+                    }
+                    if(matchingProduct == null){
+                        lineValid = false;
+                    }
+                }
+                if(lineValid){
+                    double subtotal = quantity * matchingProduct.getPrice();
+                    double discountValue = subtotal * discountPercent / 100.0;
+                    double finalCost = subtotal - discountValue;
+
+                    totalQuantity += quantity;
+                    totalFinalCost += finalCost;
+                    totalDiscountValue += discountValue;
+                }else{
+                    totalInvalidLines ++;
+                }
+            }
+        } catch (FileNotFoundException e) {
+            System.out.println("Orders file not found: " + e.getMessage());
+        }
     }
 
-    public void saveReport()
+    public void saveReport(){
-    {
+        StringBuilder report = new StringBuilder();
-        // 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
 
-        /* Example Structure
+        report.append("========= SALES REPORT =========\n");
-        ========= SALES REPORT =========
+        report.append(String.format(java.util.Locale.US, "Total Quantity Sold: %d\n", totalQuantity));
-        Total Quantity Sold: 42
+        report.append(String.format(java.util.Locale.US, "Total Final Cost: $%.2f\n", totalFinalCost));
-        Total Final Cost: $1520.75
+        report.append(String.format(java.util.Locale.US, "Total Discount Value: $%.2f\n", totalDiscountValue));
-        Total Discount Value: $230.50
+        report.append(String.format(java.util.Locale.US, "Invalid Rows: %d\n", totalInvalidLines));
-        Invalid Rows: 3
+        report.append("================================\n");
-        ================================
+
-        */
+        FileWriter writer = null;
+        try {
+            writer = new FileWriter("report.txt");
+            writer.write(report.toString());
+        } catch (IOException e) {
+            System.err.println("Error writing report file.");
+        } finally {
+            if (writer != null) {
+                try {
+                    writer.close();
+                } catch (IOException e) {
+                    System.err.println("Error closing report file.");
+                }
+            }
+        }
     }
 }