code cleanup and added mediator design pattern for report generation

src/crms/form/MainForm.java

@@ -5,14 +5,14 @@
 package crms.form;
 
 import crms.lib.CarDatabase;
-import crms.lib.CarBuilder;
 import crms.lib.CarManager;
 import crms.lib.CarReport;
 import crms.lib.Rental;
 import crms.lib.RentalDatabase;
 import crms.lib.RentalManager;
 import crms.lib.RentalReport;
 import crms.lib.RentalReport.RentalStatus;
+import crms.lib.Reporter;
 import crms.lib.gui.CarTableModel;
 import crms.lib.gui.IReportTableModel;
 import crms.lib.gui.RentDateVerifier;
@@ -992,13 +992,11 @@ private void registerCarButtonActionPerformed(java.awt.event.ActionEvent evt) {/
             return;
         }
         try {
-            var carBuilder = new CarBuilder();
-            var car = carBuilder.setId(carManager.getDatabase())
-                    .setBrand(brandTextField_add.getText())
-                    .setModel(modelTextField_add.getText())
-                    .setDescription(descriptionTextField_add.getText())
-                    .setPrice(Double.parseDouble(priceTextField_add.getText())).getResult();
-
+            var car = carManager.createCar(brandTextField_add.getText(),
+                    modelTextField_add.getText(),
+                    descriptionTextField_add.getText(),
+                    Double.parseDouble(priceTextField_add.getText())
+            );
             carManager.tryAddCar(car);
             updateCarTable(carManager.generateReport());
         } catch (Exception e) {
@@ -1185,8 +1183,14 @@ public void warn() {
     }
 
     private void initializeProgram() {
-        carManager = new CarManager(CarDatabase.getInstance(), RentalDatabase.getInstance());
-        rentalManager = new RentalManager(RentalDatabase.getInstance());
+        Reporter mediator = new Reporter();
+
+        carManager = new CarManager(CarDatabase.getInstance(), mediator);
+        rentalManager = new RentalManager(RentalDatabase.getInstance(), mediator);
+
+        mediator.setCarManager(carManager);
+        mediator.setRentalManager(rentalManager);
+
         updateCarTable(carManager.generateReport());
     }
 

src/crms/lib/Car.java

@@ -1,107 +1,38 @@
-/*
- * Click nbfs://nbhost/SystemFileSystem/Templates/Licenses/license-default.txt to change this license
- * Click nbfs://nbhost/SystemFileSystem/Templates/Classes/Class.java to edit this template
- */
 package crms.lib;
 
-/**
- * Represents a unit of a car in the system.
- * <p>
- * This class contains information about the car, including its brand, model,
- * description, price, and a unique ID.
- * </p>
- *
- * @author Yuan Suarez
- * @version 1.0
- */
 public class Car {
 
-    private String description;
-    private String brand;
-    private String model;
-    private double price;
-    private String id;
+    private final String id;
+    private final String description;
+    private final String brand;
+    private final String model;
+    private final double price;
 
-    public Car() {
-        brand = "Unknown brand";
-        model = "Unknown model";
-        price = 0;
-        id = "0000";
-        description = "No description";
-    }
-
-    public void setBrand(String brand) {
-        this.brand = brand;
-    }
-
-    public void setModel(String model) {
-        this.model = model;
-    }
-
-    public void setId(String id) {
+    public Car(String id, String brand, String model, String description, double price) {
         this.id = id;
-    }
-
-    /**
-     * Sets the price for the {@code Car}.
-     *
-     * @param price the price to set
-     */
-    public void setPrice(double price) {
+        this.description = description.trim();
+        this.brand = brand.trim();
+        this.model = model.trim();
         this.price = price;
     }
 
-    /**
-     * Gets the price of the {@code Car}.
-     *
-     * @return the price of the car
-     */
-    public double getPrice() {
-        return this.price;
-    }
-
-    /**
-     * Gets the unique ID of the {@code Car}.
-     *
-     * @return the ID of the car
-     */
     public String getId() {
         return id;
     }
 
-    /**
-     * Gets the description of the {@code Car}.
-     *
-     * @return the description of the car
-     */
     public String getDescription() {
-        return this.description;
-    }
-
-    /**
-     * Sets the description of the {@code Car}.
-     *
-     * @param description the description to set
-     */
-    public void setDescription(String description) {
-        this.description = description;
+        return description;
     }
 
-    /**
-     * Gets the brand of the {@code Car}.
-     *
-     * @return the brand of the car
-     */
     public String getBrand() {
         return brand;
     }
 
-    /**
-     * Gets the model of the {@code Car}.
-     *
-     * @return the model of the car
-     */
     public String getModel() {
         return model;
     }
+
+    public double getPrice() {
+        return price;
+    }
 }

src/crms/lib/CarDatabase.java

@@ -1,7 +1,3 @@
-/*
- * Click nbfs://nbhost/SystemFileSystem/Templates/Licenses/license-default.txt to change this license
- * Click nbfs://nbhost/SystemFileSystem/Templates/Classes/Class.java to edit this template
- */
 package crms.lib;
 
 import java.io.BufferedReader;
@@ -10,49 +6,16 @@
 import java.io.IOException;
 import java.util.ArrayList;
 
-/**
- * The {@code CarDatabase} class manages the collection of recorded {@code Car}
- * objects in the local database and performs various operations related to
- * them.
- *
- * <p>
- * It implements the singleton pattern to ensure only one instance of the class
- * exists.
- * </p>
- *
- * <p>
- * It provides methods to add, remove, and retrieve {@code Car} objects,
- * generate reports, and handle data persistence to a local file.
- * </p>
- *
- * @author Yuan Suarez
- */
 public class CarDatabase extends Database<Car> {
 
-    /**
-     * The filename where the car data is stored.
-     */
     private final String filename = "cars.txt";
 
-    /**
-     * The single instance of {@code CarDatabase}.
-     */
     private static CarDatabase instance;
 
-    /**
-     * Private constructor to prevent instantiation. Initializes the
-     * {@code cars} list.
-     */
     private CarDatabase() {
         dataList = new ArrayList<>();
     }
 
-    /**
-     * Returns the singleton instance of {@code CarDatabase}. If the instance
-     * does not exist, it is created and the cars are fetched from disk.
-     *
-     * @return the singleton instance of {@code CarDatabase}.
-     */
     public static CarDatabase getInstance() {
         if (instance == null) {
             instance = new CarDatabase();
@@ -61,13 +24,6 @@ public static CarDatabase getInstance() {
         return instance;
     }
 
-    /**
-     * Retrieves a {@code Car} object using the given ID.
-     *
-     * @param id the ID of the car to be retrieved.
-     * @return the {@code Car} object with the specified ID, or {@code null} if
-     * not found.
-     */
     @Override
     public Car getItemById(String id) {
         for (Car car : dataList) {
@@ -78,32 +34,27 @@ public Car getItemById(String id) {
         return null;
     }
 
-    /**
-     * Fetches the recorded {@code Car} objects from the file {@code cars.txt}.
-     */
     @Override
     public void fetchFromDisk() {
         try (BufferedReader reader = new BufferedReader(new FileReader(filename))) {
             while (reader.ready()) {
                 String text = reader.readLine();
                 String[] lineComponents = text.split("###");
                 dataList.add(
-                        new CarBuilder().setId(lineComponents[0])
-                                .setBrand(lineComponents[1])
-                                .setModel(lineComponents[2])
-                                .setDescription(lineComponents[3])
-                                .setPrice(Double.parseDouble(lineComponents[4])).getResult()
-                );
-
+                        new Car(
+                                lineComponents[0], // id
+                                lineComponents[1], // brand
+                                lineComponents[2], // model
+                                lineComponents[3], // description
+                                Double.parseDouble(lineComponents[4]) // price
+                        ));
             }
         } catch (IOException | NumberFormatException e) {
             System.out.println("An exception has occurred while reading " + filename);
         }
     }
 
-    /**
-     * Saves the list of {@code Car} objects to the file {@code cars.txt}.
-     */
+    @Override
     public void saveToDisk() {
         try (FileWriter fileWriter = new FileWriter(filename)) {
             StringBuilder toWrite = new StringBuilder();